Performance-Based Physical Protection and Active Assailant Attacks

By Craig S. Gundry, PSP, cATO, CHS-III
 

Robust security risk management programs integrate a number of approaches to reduce the risk of active assailant attacks. Issues such as threat recognition and assessment, reinforcement of positive workplace/school climate and culture, egress design, effective communications infrastructure, emergency planning, and employee training all contribute to reducing the probability and consequences of active shooter events. However, if measures employed to prevent attacks are unsuccessful or an outsider adversary targets the facility in a manner that evades our proactive influence, having a physical protection system (PPS) that uses a performance-based design approach becomes the most critical line of defense influencing the overall consequences of the attack.

In the context of active assailant attacks, performance-based physical security design integrates Detection, Delay, and Response elements in a manner that reconciles the time required for an adversary to commence mass killing and the time required for detection and response by security or police.

Ultimately, physical security design is a mathematics problem defined by several key times and probabilities. The main performance metric of a Physical Protection System (PPS) design is its Probability of Interruption, defined as the probability that an adversary will be detected and intercepted by a response force before he/she can complete their objective. The most important elements determining the Probability of Interruption are the Adversary Task Time (total time required for an adversary to enter a facility and access their target) and response force time. If the total time for detection, assessment, communications, and response force intervention is longer than the adversary task time, the system will fail. Specific elements alone (such as having an access control system or CCTV cameras) mean nothing outside the context of the overall system design. Individual PPS elements must work together integrally to reconcile these key times or the adversary will succeed.

In the context of active shooter events, detection usually is the result of visual or audible observation when the attack commences. Detection may also result from an alarm signal generated by forced entry into secured spaces or gunshot detection systems. The Time of Detection during an attack is represented in the diagram (below) as TD.

Once the attack is recognized, it is reported to authorities by 911/112 call or relayed through a security control room.

The time the report is received by authorities and/or assessed by a security control room for deployment of on-site armed officers is represented in the diagram (right) as TA (Time of Assessment).

After the 911/112 center or security control room is alerted, the response force is subsequently dispatched to intercept and neutralize the adversary. This is represented in the diagram (right) as the Time of Interruption (TI).

Physical Protection System Times and Functions

While the alert and response force deployment is in progress, the adversary advances through barriers and distance to access targets and initiate mass killing. The time mass killing is in progress is represented in the previous diagram as Time of Completion (TC). The Adversary Task Time is the cumulative time between the Time of Detection and the Time of Completion. If the Time of Interruption is before the Time of Completion, the Physical Protection System (PPS) is successful in its function of preventing mass killing.

In most previous active shooter attacks, deficiencies in one or more key functional elements (Detection, Delay, or Response) result in a situation where mass killing (TC) initiates before the response force intervenes (TI).

Physical Security and Active Shooter Planning

Based on data yielded during several studies of active shooter attacks, the consequences of the difference in time between commencement of mass killing and response force intervention (TC versus TI) can be estimated as one casualty per 15 seconds.[1] 

Although the ideal objective of PPS design is to interrupt mass killing before it commences, real world conditions often limit the possibility of achieving a high Probability of Interruption. Nevertheless, all measures that increase Adversary Task Time and expedite response time have a direct benefit in reducing potential casualties by narrowing the gap between TC and TI.

Sandy Hook Elementary School, 14 December 2012: Case Study of Performance-Based Protection Principles in Practical Application

 At approximately 09:34, Adam Lanza used an AR-15 rifle to shoot through a tempered glass window adjacent to the school’s locked entrance doors and passed into the lobby.[2]

 After killing the school principal and a school psychologist and injuring two other staff members who entered the hallway to investigate, Lanza entered the school office. Meanwhile, staff members concealed inside the school office and nearby rooms initiated the first calls to 911. Staff located throughout the building were alerted when the ‘all-call’ button on a telephone was accidentally activated during a 911 call.

After finding no targets in the office, Lanza returned to the hallway and proceeded into the unlocked door of first grade classroom 8 where mass murder commenced (approx. 09:36).[3] In less than two minutes, Lanza killed two teachers and fifteen students.

Sandy Hook Elementary Attack Diagram

As the attack in classroom 8 was in progress, teacher Victoria Soto and a teaching assistant in classroom 10 attempted to conceal children in cabinets and a closet.

 After exhausting targets in classroom 8, Lanza proceeded into classroom 10 and killed Ms. Soto, assistant Anne Murphy, and five children. Although the exact reason Ms. Soto did not lock the door to classroom 10 is unknown, all classrooms at Sandy Hook Elementary School featured ANSI/BHMA “classroom-function” locks which can only be locked with a key from the hallway-side of the door. 

The tragedy ended in classroom 10 when Lanza committed suicide at 09:40 while police were preparing for entry into the building.

As common in U.S. primary schools, Sandy Hook Elementary School relied on off-site police as their response force during emergency events. Response was first initiated at 09:35 when a staff member called 911 to report the crisis. At 09:36, an alert was broadcast by radio and police units were dispatched to the school. The first police unit arrived at 09:39, followed immediately by two other units. After assessing the scene and planning a point of entry, the officers organized into a contact team and made entry into the school at 09:44.

In the context of physical protection system performance, the adversary task time (time between when Lanza’s entry commenced and mass killing was in progress) at Sandy Hook Elementary School was less than one minute. The time between detection of the attack and on-site arrival of police was approximately two minutes. However, there was an additional seven minutes of time as officers assessed the situation, organized into a contact team, entered, and effectively moved to the location of classroom 10 in position to neutralize the killer. When assessing incidents involving response by off-site police, arrival time at the scene is irrelevant. What matters is the time ending when police arrive at the immediate location of the adversary ready to neutralize the threat. This describes the contrast between On-Site Response Time and Effective Response Time. At Sandy Hook Elementary School, the Effective Response Time was approximately nine minutes.

Mitigating the consequences of attack through better PPS design and integration

 

In the Newtown tragedy, PPS failure was largely the result of inadequate delay in relation to the time required for response by off-site police. When the attack is analyzed using Sandia’s Estimate of Adversary Sequence Interruption (EASI) Model, the original PPS at Sandy Hook Elementary School would have had a Probability of Interruption of 0.0006 (Very Low).

Sandy Hook Physical Security Analysis - Original PPS
Sandy Hook Physical Security Analysis - Original EASI Analysis

In the situation of Sandy Hook Elementary School, there are a number of measures that could have improved overall system performance.

Upgrade the facade with intrusion-resistant glazing. Adam Lanza entered the building by bypassing the locked entrance doors and shooting a hole through the adjacent tempered glass window. He then struck the fractured window and climbed through the breach. Tempered safety glass is generally only 4-5 times resistant to impact as annealed glass and provides minimal delay against forced intrusion. According to testing documented by Sandia National Laboratories, 0.25 inch tempered glass provides 3-9 seconds of delay against an intruder using a fire axe and the mean delay time for penetrating 1/8″ tempered glass with a hammer is 0.5 minutes.[4] However, impact testing documented by Sandia did not account for the fragility of a tempered glass specimen after first being penetrated by firearm projectile. In penetration tests Critical Intervention Services conducted of 1/4-inch tempered glass windows using several shots from a 9mm handgun to penetrate glazing prior to impact by hand, delay time was only 10 seconds.[5]

Upgrading facade glazing with the use of mechanically-attached anti-shatter film could have improved delay time at the exterior protective layer by 60-90 seconds.[6]

Construct an interior protective layer to delay access from the lobby into occupied school corridors. Once Adam Lanza breached the exterior facade into the school lobby, there were no additional barrier layers delaying access into areas occupied by students and faculty. A significant percentage of active shooter assaults by outsider adversaries originate through main entrances and progress into occupied spaces.[7] Some examples include attacks at the Riena Nightclub (2017), Pulse Nightclub (2016), Charlie Hebdo Office (2015), Inland Regional Center (2015), Colorado Springs Planned Parenthood (2015), Centre Block Parliament Bldg (2014), and US Holocaust Memorial Museum (2009).
 
An ideal lobby upgrade would be designed to facilitate reception of visitors while securing the interior of the school through a protective layer constructed of intrusion-resistant materials. Depending on material specifications, an interior barrier layer could have delayed Adam Lanza’s progress into the school by an additional 60-120 seconds.
 
Sandy Hook Elementary School Lobby Concept

Replace “classroom-function” locks on school doors with locks featuring an interior button or thumbturn. All classroom doors inside Sandy Hook Elementary were equipped with ANSI “classroom-function” locks (mortise F05 and bored F84). These are perhaps the worst choice of locks possible for lockdown purposes during active shooter events. As witnessed in a number of attacks, doors equipped with classroom-function locks often remain unlocked due to difficulty locating or manipulating keys under stress. In addition to Sandy Hook classroom 10, another incident where this situation clearly contributed to unnecessary casualties was the 2007 Virginia Tech Norris Hall attack.[8] In these two events alone, 26 students and faculty were killed and 24 wounded specifically because the doors to classrooms could not be reliably secured.

Ideal specifications for door locks would be ANSI/BHMA A156 Grade 1 with an ANSI lock code of F04 or F82.[9] Mechanical locks rated ANSI/BHMA Grade 1 have been successfully evaluated under a variety of static force and torque tests. Locks coded as F04 and F82 feature buttons or thumbturns to facilitate ease of locking under stress.

Although there are no empirical sources citing tested forced entry times against ANSI/BHMA A156 Grade 1 rated locks, it is estimated that a committed adversary using impact force with no additional tools could penetrate improved locks in approximately 90-110 seconds.

Replace door vision panels with intrusion-resistant glazing. During the attack at Sandy Hook Elementary, Adam Lanza was able to enter classrooms 8 and 10 directly through unlocked doors. If these classrooms were secured, the tempered glass vision panels on all classroom doors could have been easily breached to facilitate entry in less than 10 seconds.

An effective approach to physical security specification would ensure that all barriers composing the classroom protective layer are composed of materials with similar delay time values. This could be accomplished by ensuring that vision panels are no wider than 1.5″ (3.8 cm) or constructed of intrusion-resistant glazing such as laminated glass, polycarbonate, or reinforced with anti-shatter film.

If the aforementioned barrier improvements were employed in the PPS design at Sandy Hook Elementary School, Adam Lanza’s access into occupied classrooms would have been delayed by an additional 201-311 seconds. This would have improved the overall performance of the PPS by potentially increasing the Adversary Task Time to 206-316 seconds before mass killing was in progress. Although this is a significant improvement from the original Adversary Task Time (est. 23 seconds), 316 seconds is still less than the estimated response time of police during the original event (est. 546 seconds).

In many cases, accomplishing the performance-based objective of interrupting an active shooter before mass killing commences requires a combined approach aimed at both increasing delay time and decreasing response force time. In the case of Sandy Hook Elementary School, decreased response time could have been facilitated by the use of gunshot detection technology or duress alarms, improved communications procedures, and similar improvements. Any measure that decreases alert notification and response times has a beneficial impact on system performance. Even if enhancements only reduce response time by 10 or 15 seconds, such improvements have the theoretical benefit of reducing casualties by one victim per fifteen seconds of decreased response time.

In the situation of Sandy Hook Elementary School, the greatest improvement could have resulted from having an on-site response force (e.g., armed school resource officer) capable of reliably responding anywhere on the school campus within 120 seconds of alert.[10] If this measure were implemented, the total estimated alert and response time could have been improved to 147-157 seconds. When compared to the increased Adversary Task Time of 206-316 seconds, the improved PPS design would have likely resulted in interruption before mass homicide commenced. When analyzed using Sandia’s Estimate of Adversary Sequence Interruption (EASI) Model, the improved PPS would have resulted in a Probability of Interruption of 0.87 (Very High).

The following table and spreadsheet models the sequence of the original attack at Sandy Hook Elementary School with the PPS improvements described in this article to demonstrate how performance-based PPS design can influence the outcome of armed attacks.

Sandy Hook Physical Security Analysis - Improved PPS
Sandy Hook Physical Security Analysis - Improved EASI Analysis
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Copyright © 2018 by Craig S. Gundry, PSP, cATO, CHS-III

CIS consultants offer a range of services to assist organizations in managing risks of active shooter violence.  Contact us for more information.


References

[1] Anklam, Charles, Adam Kirby, Filipo Sharevski, and J. Eric Dietz. “Mitigating Active Shooter Impact: Analysis for Policy Options Based on Agent/computer-based Modeling.” Journal of Emergency Management 13.3 (2014): 201-16.

[2] Sedensky, Stephen J. Report of the State’s Attorney for the Judicial District of Danbury on the shootings at Sandy Hook Elementary School and 36 Yogananda Street, Newtown, Connecticut on December 14, 2012. Danbury, Ct.: Office of the State’s Attorney. Judicial District of Danbury, 2013. Print.

[3] Time estimated based on witness event descriptions and assessment of time required to walk through the school office and down the corridor to classroom 8.

[4] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978.

[5] Critical Intervention Services assisted a window film manufacturer in 2015 in conducting a series of timed penetration tests of 1/4-inch tempered glass windows with mechanically-attached 11 mil window film. The tests involved penetration by firearm followed by impact (kicking and rifle buttstock). The delay times ranged from 62 to 94 seconds and deviated according to the aggression of our penetration tester.

[6] Ibid.

[7] Gundry, Craig S. “Analysis of 20 Marauding Terrorist Firearm Attacks.” Preparing for Active Shooter Events. ASIS Europe 2017, 30 Mar. 2017, Milan, Italy.

[8] Mass Shootings at Virginia Tech. April 16, 2007. Report of the Review Panel. Virginia Tech Review Panel. August 2007. pp.13.

[9] ANSI/BHMA A156.13, Mortise Locks and Latches. Builders Hardware Manufacturers Association (BHMA), New York, NY, 2011.

[10] CIS Guardian SafeSchool Program® standards define a performance benchmark of 120 seconds as the maximum time for acceptable response by on-site officers. However, achieving this type of response time in many facilities requires careful consideration of facility geography, communications systems, access obstructions, and officer capabilities (e.g., training, physical conditioning, etc.).

Safe Rooms and The Active Shooter Threat (Part III)

By Craig S. Gundry, PSP, cATO, CHS-III

Parts One and Two of this article discussed the importance of safe rooms in active shooter planning, physical security principles related to safe room design, threat characteristics, and standards and references with potential use in specifying safe room barriers.

Part Three of this article continues by exploring options and performance expectations for safe room barrier components.

Safe Room Barrier Materials and Construction

Walls

Partition Design

Ideally, safe room walls should be designed as full partitions extending floor-to-ceiling to minimize opportunity for easy access through drop ceilings. In high-risk situations or design applications where the intervention of security or police forces is expectedly delayed, full partition walls should be a basic requirement.

In low-risk applications and situations where the primary design objective is to simply frustrate adversary access, drop ceilings may be a justifiable compromise. As described in Part One of this article, armed attackers most often use visually-obvious portals (e.g., doors and windows) as their main pathways for movement. Although entry through drop ceilings is certainly possible, our research has not revealed any active shooter attacks to date where drop ceilings were exploited as a means of accessing people located in locked rooms.

Intrusion Resistance of Walls

In alignment with the principles of balanced protection, walls should ideally resist forced intrusion with similar delay times as doors, locks, and windows. In many commercial and academic facilities, walls protecting rooms commonly designated for use as safe rooms (e.g., offices, conference rooms, classrooms, etc.) are often secured by little more than two layers of gypsum board on wooden studs. Some sources suggest two-layered drywall partitions can be penetrated in 60 seconds by an adversary without use of equipment and 30 seconds with the assistance of hand tools.[i] Despite the poor performance of gypsum board walls, they may be a justifiable compromise in some situations, considering the rare frequency of active shooter attacks where walls have been used as a point of entry into locked rooms. In low-risk applications or situations where budget limits retrofit options, we rarely recommend replacement or upgrade of existing drywall.

In medium-high risk applications and safe room designs with delay time objectives over 45 seconds, walls should be constructed using intrusion-resistant materials. Some options for protective wall construction include reinforced concrete, filled masonry block, expanded metal mesh, and polycarbonate-composite wall panels.

Reinforced concrete walls provide the best delay time performance against adversaries using limited toolsets. According to tests documented by Sandia, 4-inches of reinforced concrete with No. 5 rebar on 6-inch centers will provide approximately 4.7 minutes of delay against penetration with hand tools (including saw).[ii] If our threat definition is an adversary relying solely on firearm penetration and blunt object impact, reinforced concrete of any dimensions will provide almost indefinite delay.

Contrary to what many assume, unfilled concrete masonry unit (CMU) block walls provide minimal delay against forced entry and only slightly better performance than drywall against some methods of penetration. According to data published in the Barrier Technology Handbook, the mean delay time for penetrating an unfilled CMU block wall is only 36 seconds by the use of a sledgehammer.[iii] Unfilled CMU block walls are also susceptible to damage by rifle projectiles and may crumble when struck repeatedly by gunfire.[iv] For better performance in delaying forced entry, CMU block walls should be fully grouted and reinforced with rebar. According to tests documented by Sandia, filled 8-inch CMU walls with No. 5 rebar on 14-inch centers provide approximately 1.4 minutes of delay against penetration with hand tools.[v]

Supplementing exterior drywall layers with a securely attached inner layer of expanded metal mesh is one of the most common methods of retrofitting existing walls for improved resistance against forced entry. Expanded steel constructed of 9-gauge 3/4-inch diamond mesh is a common material specification for this purpose. In this type of wall design, the expanded metal mesh is installed on the inside of the protected room and secured to wall studs by using deep screws and fasteners specially designed for this purpose. The expanded metal barrier layer is then overlaid with gypsum board or plywood. According to Sandia, a wall constructed of two layers of 3/4-inch plywood, two layers of gypsum board, and an expanded metal mesh interlayer can provide as much as 6.5 minutes of delay against penetration with hand tools.[vi] Despite the popularity of 9-gauge material as a safe room design specification, money can often be saved by using a lighter mesh without compromising performance. If the threat definition is an adversary equipped solely with a firearm, static and dynamic impact force will be the main mechanisms of penetration, and overall strength of the fastening system will be more important than thickness of the metal fabric.

Several manufacturers currently offer polycarbonate composite wall panel products marketed for security applications. Most products of this type are composed of a thin polycarbonate layer (0.08-0.125 inch) bonded to gypsum or cement board. Manufacturers of polycarbonate composite wall systems are generally cautious about describing the capabilities of these products. Most manufacturers only cite single-impact static force tests up to 3,200 ft-lbf. When addressing impact resistance, one manufacturer cites testing under ASTM D2394-83. However, ASTM D2394 relates to the performance of finish flooring against abrasion, friction, and indentation and offers no insight on protective value. Although the concept of these products is very appealing, their use in performance-based protective design is discouraged in the absence of more reliable and promising test data.

Ballistic Resistance of Walls

One of the best references for specifying construction of bullet-resistant walls is U.S. DoD UFC 4-023-07 (Design to Resist Direct Fire Weapon Effects). [vii] According to UFC 4-023-07, walls constructed of 4-inches reinforced concrete, 8-inch filled CMU block (grouted full), and 8-inches of brick will resist penetration by 7.62x51mm ammunition.[viii] UFC 4-023-07 also provides ballistic resistance specifications for steel plate barriers. However, at the thicknesses specified by DoD, steel is not a practical option in most indoor design situations due to structural load and construction challenges. 

A number of manufacturers also produce fiberglass wall panels rated for ballistic resistance under UL 752, ASTM F1233-08, and EN 1063.[ix][x][xi] Minimum specifications for protection against military small arms (5.56mm) would be UL 752 Level 7, F1233 R1, or EN 1063 BR5. More conservative specifications for 7.62x51mm include UL 752 Level 8, F1233 R3, and EN 1063 BR6.

In addition to fiberglass panels, Saab’s Barracuda Soft Armor offers an easy method for upgrading hollow walls into bullet-resistant barriers. The Barracuda Soft Armor is designed as 13mm ceramic balls used as infilling between wall boards. Thickness of the armor-filled wall cavity determines its ballistic resistance capabilities. According to Saab’s product literature, 100mm of Barracuda pellets is the technically-estimated specification for protection against 7.62mm FMJ projectiles and 120mm of Barracuda armor has been technically-verified as ~99% effective in resisting 7.62mm armor piercing ammunition.[xii] Although Saab does not cite tested ratings according to UL 752 or EN 1063, 125mm Barracuda armor has been certified as STANAG 4569 Level 3 (7.62x54R and 7.62x51AP).[xiii]

Doors

If the risk level and design approach requires door systems rated for tested delay times, doors certified under SD-STD-01.01, ASTM F3038-14, CPNI MFES, LPS 1175 have been tested against a variety of forced entry methods and often exceed requirements for protection during short-duration armed events. If the threat definition identifies an adversary solely employing firearms and expedient tools, any door certified under SD-STD-01.01, ASTM F3038-14, CPNI MFES, or LPS 1175 will likely far exceed performance as suggested by its certified delay time rating.

Considering the cost of security doors and the number of rooms often desired for availability as safe rooms during armed attacks, many organizations do not have the budget or risk justification required for implementing security doors rated under forced entry standards. In this situation, specification may require choosing commercial door hardware with security features adequate to accomplish the design objective or retrofitting existing doors with cost-consciously selected upgrades for maximum benefit.

Intrusion Resistance of Doors

As a general rule, outward-swinging doors provide the best protection against exterior ramming force due to resistance of the rebate within the frame. Additionally, adversaries attempting to pull open locked outward-swinging doors without the aid of tools are at a great mechanical disadvantage. If rooms earmarked as potential safe rooms feature existing inward-swinging doors, door hardware (e.g., locks, strikes, and frames) should be carefully specified to ensure adequate resistance against ramming force.

Most security doors certified under forced entry standards are constructed of steel. However, indoor rooms potentially earmarked for use as safe rooms in office and academic facilities are often equipped with solid core wood or solid wooden doors. Solid core doors are constructed with a composite wood core and overlaid with hardwood veneer for aesthetic appearance. The times required to penetrate solid core and solid wooden doors using methods likely to be encountered during active shooter attacks has never been published. Considering the materials involved, solid wooden doors are preferable to solid core doors. Nevertheless, for application against a gunman employing impact force without additional tools, solid door leafs (regardless of construction) are unlikely to be the point of failure when compared to the potential vulnerability of locks, strikes, wooden frames, and vision panels.

Doors featuring glass vision panels are often highly vulnerable to forced entry. Tempered safety glass panels only provide about 10 seconds of delay against a gunman. Once broken, the intruder can simply reach through the window and manipulate the inner door handle or lock to gain entry. To limit this vulnerability, vision panels should be no wider than 1.5″ (3.8 cm) or constructed of intrusion-resistant glazing such as laminated glass, polycarbonate, or reinforced with anti-shatter film. If the delay time objective exceeds a few minutes, vision panels should be avoided completely. Although there are door sets rated under LPS 1175 and ASTM forced entry standards which feature vision panels, it is generally impractical to upgrade or replace vision panels on commercial doors to sufficiently achieve more than a few minutes of delay.

In situations where performance objectives exceed 15 minutes of delay or adversaries are expected to possess a diverse toolset, security hinges should be installed on safe room doors to reduce the risk of hinge pin removal or cutting. Security hinges with dog bolts can also aid in reducing vulnerability to some tool-aided methods of entry. All door frames on safe rooms (regardless of application) should be constructed of steel.

If the budget and risk level justify installation of doors rated under security standards, specifications for a basic level of forced entry resistance include EN 1627 RC4+ and LPS 1175 SR2+. For higher levels of protection, specifications using ASTM 3038, SD-STD-01.01, and CPNI MFES provide a more reliable basis for delay time performance.

Ballistic Resistance of Doors

Although the author is not aware of any comprehensive published ballistic tests of common commercial door products, it is safe to assume most commercial steel, wooden, and solid core doors are vulnerable to penetration by military small arms. If safe room design objectives require ballistic protection, doors rated UL 752 level 7+ or EN 1522 FB5+ should be specified. Additionally, all doors rated under SD-STD-01.01 have been tested against penetration by 5.56mm, 7.62x51mm, and 12-gauge shotgun.

Locks

 Simplified Locking

As a prerequisite criterion, all mechanical locks on safe room doors should feature thumbturns for ease of locking under stress. In several previous active shooter attacks, critical doors on rooms where people were seeking refuge remained unlocked during the event owing to absence of a key.[xiv] Additionally, good preparation for active shooter events should anticipate the effects of the Sympathetic Nervous System (SNS) on employee response. During high stress events, the SNS is often activated with impairing effects on cognitive function and fine motor coordination. These negative effects of the SNS can interfere with even simple tasks such as locating and manipulating keys.

Ironically, considering the history of active shooter attacks in American schools, locks classified by ANSI as “classroom function” (mortise F05 and bored F84) are perhaps the worst choice for safe room applications and should be avoided when possible. Classroom function locks are only lockable by a key from the outer side of the door. Not only do these locks require a key, but they also require the occupant to open the door and reach into the hallway to secure the lock.

 Intrusion Resistance of Locks

For protection against entry by buttstock impact and kicking, all lever and knob sets on safe room doors should ideally be rated ANSI/BHMA A156 Grade 1 or have a minimum Security Grade of 4 under EN 12209.[xv][xvi] Mechanical locks rated ANSI/BHMA Grade 1 and EN 12209 Security Grade 4+ have been successfully evaluated under a variety of static force and torque tests.

If the design objective is to simply frustrate access by non-committed adversaries, doors secured only by ANSI/BHMA Grade 1 or EN 12209 Security Grade 4+ latch locksets may be sufficient. However, if the design objective is to delay penetration by a committed adversary or the threat definition includes a diverse range of entry tools, locksets should feature a deadbolt or augmented by the installation of an independent deadbolt lock. In medium security applications, single-point deadbolt locks are often adequate. In situations where greater delay times are required or adversaries are expected to employ improved toolsets for entry, multi-point deadbolt systems provide the best protection.

Surface-mounted deadbolt locks are generally superior to mortise and bored locks in resisting forced entry. Surface-mounted deadbolt locks can incorporate bolts unconstrained by the thickness of doors and require the adversary to entirely penetrate the door leaf to access the lock.[xvii] Surface-mounted deadbolt systems are also less vulnerable to prying due to the increased force necessary to lever the entire door frame.

Many surface-mounted deadbolt systems designed for high security applications feature auto-bolting locks. Auto-bolting systems lock automatically when the door is closed and often disengage automatically when the inside handle is operated for exit. Manually-bolted surface-mounted deadbolts require a manual unlocking operation to permit exit. Building and life safety codes should be reviewed to ensure permissibility before installing manually-bolted surface-mounted locks. Although some jurisdictions prohibit use of manually-bolted locks on school classroom doors, manually-bolted surface-mounted deadbolts are fully permissible in most locations except when installed on egress doors. This generally addresses most concerns regarding upgrading offices, conference rooms, and similar locations as safe rooms. Under International Building Code 2012, surface-mounted deadbolts are also permissible on egress doors in certain circumstances. For instance, IBC 1008.1.9.4 (Bolt Locks) contains a rule exception for use of surface-mounted deadbolt locks on egress doors with occupant loads of less than 50 persons in Group B (Business Group), F (Factory), and S (Storage) occupancies.[xviii]

Ballistic Resistance of Locks

Another issue to consider in safe room design is the vulnerability of door hardware to ballistic damage. Although forced entry by ballistic attack against locks and hinges has been rare during active shooter events, a number of incidents have occurred where adversaries forcibly entered/or attempted to penetrate rooms by destroying door locks with gunfire.[xix]

The only product certification standard that specifically addresses door locks as a component of ballistic testing is the U.S. Department of State’s SD-STD-01.01.[xx] Withstanding a handful of exceptions, most lock manufacturers do not subject standard products to ballistic testing in accordance with protocols such as UL 752 and EN 1522.

Furthermore, Sandia National Laboratories and similar research institutions have not published empirical test data to assist in estimating the ballistic vulnerability of locks commonly used in academic and commercial facilities. In the absence of definitive references, perhaps one of the best sources we have for estimating the performance of common door locks against firearm-aided penetration is the television program MythBusters Special 9 “Shootin’ Locks.”[xxi] Although the sample size tested by MythBusters was very small, the results of testing suggest that bored deadbolt locks are resistant to single-shot penetration by handgun calibers (9mm and .357 magnum) and vulnerable to defeat by high powered rifle (.30-06 cal.) and 12-ga. shotgun slugs. U.S. Army field manual FM 3-21 also states that a shotgun is effective at defeating door locks.[xxii] Regarding rifle calibers, FM 3-21 somewhat conflicts with the Mythbusters findings by stating that 5.56mm and 7.62mm “have proved to be virtually ineffective for breaching.”[xxiii] From these limited sources, it’s reasonable to assume most locks will be resistant to critical damage by handguns, definitely vulnerable to shotguns, and susceptible to some rifle calibers (albeit, inconclusive as to exactly which rifle calibers and ammunition).

The best approach to this concern is specification of door sets rated under SD-STD-01.01. An alternative option is employing independent door and lock assemblies rated UL 752 level 7+ or EN 1522 FB5+. Surelock McGill, for example, offers a number of lock assemblies and cylinder guards rated EN 1522 up to level FB7.[xxiv]

For organizations without the budget and/or risk justification to equip safe rooms with door sets rated under ballistic resistance standards, the next best option is installing surface-mounted deadbolt locks on the inside of solid wooden or steel doors. Although most solid wooden and steel pedestrian doors are vulnerable to penetration by small arms, the door material will provide some reduction in bullet velocity and conceal location of the lock to reduce hit probability. Augmenting existing locks with bullet-resistant cylinder guards certified under UL 752 and/or EN 1522 is another possible enhancement. Conventional steel wrap-around door knob plates are not bullet-resistant, but may offer a marginal benefit by reducing projectile velocity. Additionally, bored locks may be preferred to mortise locks due to their smaller target size. As an additional concern regarding mortise locksets, wooden doors may critically weaken when struck repeatedly by gunfire in the location of the mortise pocket due to the thin layers of wood in this area.

Electrified Locks and Access Control Design

If a facility is employing/or planning to use electrified locks on potential safe room doors, careful consideration should be used in configuration of the access control system and hardware specification. Although access control systems offer great versatility in security design, they often suffer from vulnerabilities in real world application, which can be problematic during active shooter attacks.

In many buildings the author has assessed over the past several years, facilities were designed as large workspaces with few offices, storage rooms, or conference rooms suitable for use as safe rooms. In some of these facilities, permissions were broadly granted to employees through the facility’s access control system to allow convenient access to conference rooms and shared offices. During an attack by an insider adversary, doors with broadly applied access privileges will not provide useful protection. Likewise, if the access control system in the facility employs card readers and an outsider adversary recovers an access badge from a fallen employee, all doors with universal access will be compromised.

Another common problem relates to the fail-safe/secure configuration of electrified locking systems. Building and life safety codes universally require that egress doors equipped with electromagnetic locks ‘fail safe’ (unlocked) during fire alarms.[xxv] Although safe room doors in most situations will not be classified as egress doors, the author has discovered a number of facilities during his consulting activity where all access-controlled doors were universally configured to fail safe due to poor system design. In this situation, all fire alarm pull stations in the facility are ‘virtual master keys’ and would compromise most doors if someone activated a pull handle. This is a very real concern. In a number of previous attacks, fire alarms were manually activated by building occupants to alert others (e.g., 2013 Washington Navy Yard) or used by adversaries to deceptively herd victims outdoors for ambush (e.g., 1998 Westside Middle School, 2013 UCF, 2015 North Africa Hotel, etc.).[xxvi][xxvii]

In addition to fire alarms, electromagnetic locks without emergency power support fail safe automatically during electrical failures. Electromagnetic locks also fail safe by virtue of basic function if electrical lines are damaged (such as during an IED attack). Doors employing mechanical locksets and electric strikes configured to fail secure during power disruption are less vulnerable to compromise by electrical failure and fire alarms, but may be more vulnerable to forced entry than doors solely equipped with mechanical locks. Consequentially, CPNI in the United Kingdom specifically discourages use of electric strike plates on security doors.[xxviii]

 If designated safe rooms are already equipped with electrified locks, all aforementioned concerns can be mitigated by installing independent mechanical deadbolt locks for emergency use.

 Windows

 As a general rule, window and door glazing should be avoided in high risk situations or applications where designers seek ambitious delay goals. Although there are glazing products capable of high delay times, such systems are quite expensive by comparison to the price of wall construction and doors. In low-medium risk applications and situations where glazing is an unavoidable element of architectural aesthetics, windows should be designed to adequately resist intrusion. As described in part one of this article, adversaries most often focus penetration efforts on visually-obvious portals, and windows are often perceived as a vulnerable point for entry. Consequentially, the performance of glazing should be a top priority and may even exceed the importance of delay provided by barriers along less obvious intrusion paths such as walls, floors, and ceilings. 

Window Dimensions (Unprotected Glass Windows)

In accordance with U.S. DoD recommendations, all unprotected windows on safe rooms should be 96 in2 (619 cm2) or smaller.[xxix] In addition the U.S. DoD guideline, we recommend that any unprotected glass windows or vision panels within arm’s reach (approx. 36″ or 91.5 cm) of door handles and locks have a width of no more than 1.5″ (3.8 cm).

Intrusion Resistance of Windows and Glazing

If window dimensions do not conform to the aforementioned guidelines, glass should be replaced or upgraded with intrusion-resistant materials. Tempered safety glass is generally only 4-5 times resistant to impact as annealed glass and provides minimal delay against forced intrusion. According to testing documented by Sandia, 0.25 inch tempered glass provides 3-9 seconds of delay against an intruder using a fire axe and the mean delay time for penetrating 1/8″ tempered glass with a hammer is 0.5 minutes.[xxx] Furthermore, impact testing documented by Sandia did not account for the fragility of tempered glass after first being penetrated by firearm projectile. In penetration tests Critical Intervention Services conducted of 1/4-inch tempered glass windows using several shots from a 9mm handgun prior to impact by hand, delay time was only 10 seconds.[xxxi]

Some intrusion-resistant glazing options appropriate in low-medium risk applications include laminated glass, polycarbonate, and glass reinforced with properly attached anti-shatter film.

Laminated glass is a composite material constructed of two or more layers of glass bonded to a PVB or polycarbonate interlayer. According to Sandia’s test data, 1/4-inch laminated glass provides 18-54 seconds of delay against forced entry by fire axe and the mean delay time for penetrating 9/16-inch laminated security glass is approximately 1.5 minutes by hand tools.[xxxii][xxxiii] Most glazing products tested and rated under forced entry standards UL 972 and EN 356 are constructed of laminated glass.

Polycarbonate is another option for intrusion-resistant windows. At thinner dimensions, polycarbonate provides decent impact resistance but comparable performance to tempered glass against fire axe attacks.[xxxiv] Polycarbonate truly distinguishes its benefit at thicknesses of 1/2-inch or greater. According to tests documented by the Nuclear Security Systems Directorate, 1/2-inch polycarbonate can delay hand tool penetration for up to two minutes.[xxxv] Sandia cites 2-6 minutes of delay for penetration of polycarbonate by fire axe and sledgehammer.[xxxvi] Polycarbonate is relatively inexpensive and can be purchased as sheets and cut to dimensions as needed. The main disadvantages of polycarbonate are its limited resistance to scratch damage and susceptibility to discoloration and degradation from UV exposure.[xxxvii] Some tests also suggest polycarbonate may be vulnerable to fragmentation and shatter critically when penetrated by 12-gauge shotgun.[xxxviii]

In low risk situations or circumstances where budget does not permit replacing existing glazing, anti-shatter film properly attached and anchored to tempered or annealed glass may be a cost-effective alternative. Regretfully, Sandia never published data on the penetration times of film-reinforced glazing. In 2015, CIS participated in a series of tests of 1/4-inch tempered glass windows with mechanically-attached 11 mil window film. The tests involved penetration by firearm followed by impact (kicking and rifle buttstock). The delay times ranged from 62 to 94 seconds and deviated according to the aggression of our penetration tester.[xxxix] Although the sample size was small, the CIS test times at least provide a reasonable expectation for performance of window film during active shooter attacks. If anti-shatter film is chosen as an upgrade, specifications should require mechanical or cement bond frame attachment.

To facilitate performance in safe room designs with delay time goals over 60 seconds, it is recommended that designers use glazing products rated for intrusion resistance under ASTM F1233-08, EN 356, and EN 1627. If the threat definition identifies firearm penetration and buttstock impact as the primary methods of entry, reasonable specifications include ASTM F1233-08 Class 2+ Body Passage, EN 356 P6B+, and EN 1627 RC4+. UL 972 is another option, but in the author’s opinion should only be specified in low-medium risk applications. See Part II of this article for a survey of window protection standards and their relevant merits and disadvantages in safe room design.

Ballistic Resistance and Windows

For ballistic resistance, specifications for protection against military small arms include EN 1063 BR5-BR7, UL 752 Level 7-9, and ASTM F1233-08 R1-R4AP.

Ceilings and Floors

Although penetration through ceilings or floors is possible, such paths of entry are least likely considering typical construction characteristics and adversary behavior as witnessed during previous armed attacks. However, in high risk design applications, floors and ceilings should provide balanced protection according to the safe room’s specified delay time objectives. For this purpose, Sandia’s Barrier Technology Handbook provides a good survey of penetration times for a wide range of ceiling and floor construction variations.[xl]

The next part of this article surveys additional considerations for safe room planning (e.g., occupancy load, fire protection, communications, safe room kits, etc.), model examples of safe room designs, and approaches to common implementation challenges.

Continued in Part IV (Coming Soon)

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References

[i] Hypothetical Facility Exercise Data. Hypothetical Atomic Research Institute (HARI). The Twenty-Sixth Annual Training Course. U.S. Department of Energy. N.p. N.d. pp. 48.

ii] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978. pp. 4.2-6

iii] Ibid. pp. 4.5-2

iv] The vulnerability of unfilled concrete block walls to penetration and potential failure by gunfire is well demonstrated by numerous “backyard test” videos posted on YouTube. Most videos posted on YouTube display the vulnerability of stacked block walls without mortar. Finished walls will likely be more resistant to critical failure. Example: https://www.youtube.com/watch?v=Hxn8TS9cb3o

v] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978. pp. 4.5-2

vi] Ibid. pp. 4.9-1,2

vii] UFC 4-023-07, Design To Resist Direct Fire Weapons Effects. US Department of Defense, N.p.: 2008.

viii] Ibid. pp 5-8

ix] UL 752, Standard for Bullet-Resisting Equipment. UL, N.p.: 2005.

x] ASTM F1233-08, Standard Test Method for Security Glazing Materials And Systems. ASTM International, West Conshohocken, PA, 2013

xi] EN 1063:2000, Glass in building – Security glazing – Testing and classification of resistance against bullet attack. European Committee for Standardization, Brussels, 2000.

xii] Saab Barracuda Soft Armour. (Product Brochure). Saab Barracuda AB. N.p. N.d.

xiii] Ibid.

xiv] One example is the December 2017 shooting at Aztec High School. Matthews, Justin. “Substitute unable to lock doors during shooting.” KOAT Action News. 9 December 2017. http://www.koat.com/article/substitute-unable-to-lock-doors-during-shooting/14399571. Accessed 17 December 2017.

xv] ANSI/BHMA A156.13, Mortise Locks and Latches. Builders Hardware Manufacturers Association (BHMA), New York, NY, 2011.

xvi] EN 12209, Building hardware – locks and latches – mechanically operated locks, latches and locking plates. European Committee for Standardization, Brussels, 2016.

xvii] Door Security. A Guide to Security Doorsets and Associated Locking Hardware. Centre for Protection of National Infrastructure. N.p. June 2013. pp. 20

xviii] 2012 International Building Code. Chapter 10 (Means of Egress). International Code Council. N.p. 2012.

xix] Examples include the 2013 shooting at the Santa Monica College Library and a 2015 attack against a hotel in North Africa (details confidential).

xx] SD-STD-01.01, Revision G. Certification Standard. Forced Entry and Ballistic Resistance of Structural Systems. U.S. Department of State, Bureau of Diplomatic Security, Washington, DC, 1993.

xxi] MythBusters Special 9. Mega-Movie Myths 2-Hour Special. MythBusters. 2006. https://www.discovery.com/tv-shows/mythbusters/videos/mega-movie-myths-shootin-locks

xxii] FM 3-21.8, The Infantry Rifle Platoon and Squad. Headquarters Department of the Army. Washington, DC. 28 March 2007. pp. F-20

xxiii] Ibid.

xxiv] High performance door solutions. NASL-017. (Product Catalog). Surelock McGill. N.p. 2017.

xxv] 2012 International Building Code. Chapter 10 (Means of Egress). International Code Council. N.p. 2012.

xxvi] After Action Report. Washington Navy Yard. September 16, 2013. Internal Review of the Metropolitan Police Department. Metropolitan Police Department. Washington, D.C. July 2014. pp.14

xxvii] Harms, A.G. UCF After-Action Review. Tower #1 Shooting Incident. March 18, 2013. Final Report. N.p. May 31, 2013. pp. AAR-14

xxviii] Door Security. A Guide to Security Doorsets and Associated Locking Hardware. Centre for Protection of National Infrastructure. N.p. June 2013. pp. 27

xxix] UFC 4-023-10, Safe Havens. US Department of Defense, N.p., 2010. pp. 42

xxx] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978. pp. 16.3-39

xxxi] Critical Intervention Services assisted window film manufacturer Solar Gard Saint-Gobain in 2015 in conducting a series of timed penetration tests of unprotected tempered glass windows and glazing reinforced with anti-shatter film. The author personally supervised and witnessed these tests.

xxxii] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978.

xxxiii] Garcia, Mary Lynn. Design and Evaluation of Physical Protection Systems. Burlington, MA: Elsevier Butterworth-Heinemann, 2007.

xxxiv] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978.

xxxv] Garcia, Mary Lynn. Design and Evaluation of Physical Protection Systems. Burlington, MA: Elsevier Butterworth-Heinemann, 2007.

xxxvi] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978.

xxxvii] Tjandraatmadja, G.F., and Burn, L.S.  “The Effects of Ultraviolet Radiation on Polycarbonate Glazing. Durability of Building Materials and Components.” Institute for Research in Construction, Ottawa, ON. pp. 884-898

xxxviii] Hutson, Bill. Hut’s Ballistic Tests. http://www.huts.com/Huts%27sBallisticTest.htm

xxxix] Results of original tests conducted by Critical Intervention Services in cooperation with window film manufacturer Solar Gard.

xl] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978. pp. 16.3-27-16.3-32

Safe Rooms and The Active Shooter Threat (Part II)

By Craig S. Gundry, PSP, cATO, CHS-III

Part One of this article  discussed the importance of safe rooms in active shooter planning, physical security principles related to safe room design, and threat characteristics. Part Two, as follows, continues with an exploration of standards and references with potential use in specifying safe room barriers.

Safe Room Barrier Design and Construction

Forced Entry Standards and References

The key performance measure of a safe room barrier is its delay time as determined by adversary tools and methods. Ideally, all barriers defining the safe room as an independent protective layer (e.g., doors, glazing, locks, etc.) should be designed using the principles of balanced protection and provide delay as required to meet the system performance goal. Like a chain whose strength is defined by its weakest link, a safe room (or any protective layer) is only as effective as its weakest barrier or most easily exploited bypass.

For many types of barriers (e.g., reinforced concrete walls, glass glazing, etc.), delay time against some entry methods can be estimated by referencing testing data as published in Sandia National Laboratories’ Barrier Technology Handbook.[i] In the late 1970’s, Sandia collated penetration test data about different barrier types and construction variations to serve as a standard reference for security planners in the U.S. Government community. To this day, the Barrier Technology Handbook remains the “gold standard” reference for delay time data regarding many barrier types.

Although Sandia’s Barrier Technology Handbook is a useful reference, there are many barrier types and construction variations common today in commercial and academic facilities that were not tested or documented at the time of publication. Additionally, many methods of entry documented by Sandia have limited application in protecting against an adversary using a firearm as an aid in barrier penetration. For example, Sandia cites the mean delay time for penetrating 1/8″ tempered glass with a blunt tool (hammer) as 0.5 minutes.[ii] In penetration tests our company conducted of tempered glass windows using several shots from a 5.56mm rifle to penetrate glazing prior to impact by hand, delay time was only 10 seconds.[iii]

In the absence of reliable delay time data for many barrier types, security planners often need to rely on performance standards and ratings developed by organizations such as ANSI, ASTM, UL, CEN, and others. The best standards for specifying manufactured barrier products in a performance-based physical security design are those that most closely replicate the methods and tools likely to be employed by the defined threat and rate products based on delay time performance.

Several specification standards encompass impact testing and employ delay time performance as the primary basis for rating doors, glazing, and wall systems. Some of these standards include the U.S. State Department’s SD-STD-01.01, ASTM F3038-14, CPNI Manual Forced Entry Standard (MFES), and LPS 1175. [iv][v][vi][vii]

The SD-STD-01.01 test protocol is designed to replicate the conditions of a mob attempting to forcibly penetrate a barrier specimen. The protocol involves a series of ballistic tests against different parts of the specimen (shotgun, 5.56mm, and 7.62 NATO), and forced entry tests involving a team of aggressors conducting a series of attacks against the specimen at different parts with the use of various tools (e.g., ram, sledgehammer, saw, bolt cutters, pry bar, chisel and hammer, etc.). The tools and number of active test personnel varies based on time of test. Specimens are rated according to their timed forced entry-resistance against three attack levels: Five minutes (two test personnel), Fifteen minutes (six test personnel and larger range of tools), or Sixty minutes (six test personnel and greatest range of tools).

The ASTM F3038-14 testing protocol is structured similarly to SD-STD-01.01, but with some differences regarding number of attackers, ballistic resistance testing, and rating scale levels. ASTM’s testing approach involves six persons conducting a series of aggressive attacks against the barrier specimen with the use of various tools (e.g., ram, sledgehammer, saw, bolt cutters, pry bar, chisel and hammer, etc.). Different parts of the barrier are subjected to independent timed tests. When an opening large enough for test shape is breached and the object is passed through, the test is concluded.  Specimens are rated according to their timed forced entry-resistance against four levels of attack: Five minutes, Fifteen minutes, Thirty minutes, or Sixty minutes.

In the United Kingdom, CPNI’s Manual Forced Entry Standard (MFES) uses delay time against forced penetration as the basis for assigning performance ratings. The CPNI standard defines three levels of adversary (Novice, Knowledgeable, and Expert) in alignment with three threat levels (BASE, ENHANCED, and HIGH). Testing under each threat level involves two attackers, and each adversary category defines specific capabilities (e.g., tool sets, skill and experience, product knowledge, etc.). MFES resistance time classifications are defined by describing the threat level and delay time performance in increments from 0-20 minutes.

The UK’s LPS 1175 also uses delay time as the basis for designating Security Ratings for barrier products including doors, windows, etc. Tests involve a single adversary and eight tool categories (A, B, C, D, D+, E, F, G), including a diverse range of impact, prying, and power tools. Each category references an adversary tactic, skill, tool set, desire to remain covert or overt, and motivation. Warrington Certification’s STS 202 is another standard in the U.K. encompassing similar test protocols and a delay time rating scheme.[viii]

Unfortunately, all of the aforementioned standards (SD-STD-01.01, ASTM F3038-14, CPNI MFES, LPS 1175, and STS 202) encompass tests with tools unlikely to be encountered in armed assaults (e.g., sledgehammers, chisels, pry bars, power tools, etc.). Also, the number of test personnel used in SD-STD-01.01 (at higher levels) and ASTM F3038-14 is much greater than realistically expected in armed attacks in Europe or North America. For standards such as these, choosing a barrier by simply matching delay time ratings to literal delay time goals may result in overkill for situations where protection against armed attacks is the principal objective. Although there is nothing wrong with conservative specification when the risk level is high or funds permit, many organizations with limited budgets may be wasting money that could be applied elsewhere.

Other standards employ pass/fail tests as the basis for rating. One example is ASTM F1233-08 (Standard Test Method for Security Glazing Materials and Systems), a common standard for defining requirements against forced entry in the United States.[ix] The ASTM F1233-08 protocol has a ballistic testing component and separate tests for forced entry protection using different tools based on five resistance classifications. Although the ASTM F1233-08 standard has merits for certain applications and includes a test procedure for ballistic resistance, the tool sets and sequence of tests defined in ASTM F1233-08 do not realistically replicate the methods of entry and tools likely to be employed by armed attackers in live assaults.

Another American standard, UL 972 (Burglary-Resisting Glazing Material) uses dynamic load testing to simulate burglary attempts by the use of blunt object impact.[x] The UL 972 standard employs two separate procedures for High Impact Testing and Multiple Impact Testing. Both test procedures employ a 5 lb (2.3 kg) steel ball dropped at different heights (single impact at 40 feet and five impacts at 10 feet). UL 972 is not optimal for specifying protection against forced entry in active shooter attacks. First, the testing procedure in UL 972 does not consider the potential fragility of a glass specimen after first being penetrated by firearm projectile. Additionally, dynamic load testing does not provide useful delay time data necessary for determining the effectiveness of a safe room as one of several protective layers in an overall physical protection system (PPS) design. Quantitative performance-based PPS analysis tools, such as the Estimate of Adversary Sequence Interruption (EASI) model, require delay time input values that cannot be inferred from UL 972’s pass/fail type tests.[xi]

EN 1627 and related standards EN 1628, EN 1629, and EN 1630 are commonly used in Europe and elsewhere to specify protective requirements for doors, windows, and similar barriers.[xii][xiii][xiv][xv] Tests performed under these standards include pendulum impactor strikes at various points to simulate a forced entry by kicking or blunt object impact (EN 1629), static load imparted by a mechanically-operated pressure pad system (EN 1628), and timed forced entry using various tools (EN 1630). Specimens are rated into one of six resistance classes based on overall performance against dynamic and static load tests and timed tool tests (e.g., cylinder extraction, cylinder twisting, etc.). Each resistance class relates to an anticipated threat (burglar, tools, and tactics) as defined in EN 1627. Unfortunately, as described previously regarding UL 972, dynamic and static load testing is not useful in a security design based on delay time objectives or collective PPS performance. Additionally, the tool sets defined in EN 1630 are also mostly burglary tools irrelevant during active shooter attacks.

EN 356 is another CEN standard related to vulnerability of glazing systems against forced entry methods.[xvi] EN 356 uses a dropped impactor (4.11 kg steel sphere) and separate testing with a mechanically-operated fire axe to simulate burglary methods. Resistance against impact energy (based on height of impactor drop) and number of axe strikes determines the category of resistance. In the author’s opinion, EN 356 is also a suboptimal standard for defining protective requirements in safe room design for similar reasons mentioned in reference to EN 1627-1630 (e.g., tool sets, dynamic load resistance versus delay time, etc.).

Two related standards regarding mechanical locks with application in defining requirements for active shooter protection are ANSI/BHMA A156.2 (Bored and Preassembled Locks and Latches) and ANSI/BHMA A156.13 (Mortise Locks and Latches).[xvii][xviii] The ANSI/BHMA test procedures are designed to certify the durability, function, and strength of mechanical locks and latches against a series of static force and torque tests. Lock sets are classified into three grades (Grade 1-3) according to performance on all tests. Outside the United States, EN 12209 includes many of the same types of tests. Although ANSI/BHMA A156 and EN 12209 do not employ delay time as a basis for rating, they are some of the few standards that specifically evaluate door locksets against physical force. Most other standards related to security of mechanical locks (e.g., UL 437, EN 1303, etc.) evaluate performance against tool-aided methods of entry applicable to burglary (e.g., picking, impressioning, drilling, extraction, etc .) but unlikely to be used in armed assaults.

Some additional standards with potential application in specifying barrier products for use against forced entry in safe room designs include:

    • ASTM F2322 – Physical Assault on Fixed Horizontal Barriers for Detention and Correctional Facilities
    • ASTM F426 – Standard Test Method for Security of Swinging Door Assemblies
    • ASTM F1915 – Standard Test Methods for Glazing for Detention Facilities
    • ASTM F1450 – Standard Test Methods for Hollow Metal Swinging Door Assemblies for Detention and Correctional Facilities

Ballistic Protection References and Standards

The most useful reference for specifying design and construction of bullet-resistant structural walls is U.S. Department of Defense UFC 4-023-07 (Design to Resist Direct Fire Weapons Effects).[xix] UFC 4-023-07 Table 5-3 provides guidance on the construction of structural barriers to resist four levels of ballistic threat. If a safe room designer uses 7.62x51mm NATO ammunition (or lesser caliber such as 5.56mm or 7.62x39mm) as the defined threat caliber, requirements would be defined by the ‘MEDIUM’ threat level category.[xx]

UFC 4-023-07 also provides specifications on the minimum thickness of bullet-resistant fiberglass materials. However, a more reliable approach is to reference the performance data of specific fiberglass products as tested in accordance with industry standards.

Manufactured bullet-resistant products (e.g., doors, glazing, fiberglass panels, armor products, etc.) are normally tested and rated in accordance with several standards including UL 752, ASTM F1233-08, EN 1063, EN 1522, NIJ Standard-0101.06, and SD-STD-01.01.

In the United States, the two most common standards for specifying bullet-resistant building products are UL 752 and ASTM F1233-08. [xxi][xxii]

UL 752 describes grades of ballistic resistance using ten levels encompassing weapon calibers ranging from 9mm handgun up to .50 caliber rifle plus an additional level for 12 gauge shotgun. The ammunition and number of shots the specimen resists (1, 3, or 5 shots) defines the Class Threat Level of the product. Under the UL 752 rating system, adequate specifications for protection against military small arms would define UL 752 Level 7 (5.56mm x 5 shots), Level 8 (7.62x51mm x 5 shots), or Level 9 (.30 caliber armor-piercing x 1 shot).

ASTM F1233-08 uses a scale of eleven Classes/Levels to describe the ballistic resistance of glazing systems. Under the ASTM F1233 rating system, specimens must successfully resist penetration by one or three shots from defined weapon calibers ranging from .38 cal up to .30-06 armor piercing ammunition and 12 gauge shotgun. Under the ASTM F1233 rating system­, specifications for protection against military small arms would define F1233 R1 (5.56mm x 3 shots), F1233 R3 (.308 Win./7.62x51mm x 3 shots), or F1233 R4-AP (.30-06 M2-AP x 1 shot).

In the U.S., bullet-resistant body and vehicle armor are normally tested and classified according to NIJ Standard-0101.06.[xxiii] The NIJ standard uses a six level type classification system to define protection levels. For classification under Types I through III, specimens must resist penetration by five shots according to the standard’s test procedure. Type IV armor products must resist a single shot by .30-06 armor-piercing ammunition. Although NIJ Standard-0101.06 is primarily designed for testing body armor, manufacturers of bullet-resistant building materials often test their products according to the NIJ standard in addition to others. If a security planner uses NIJ Standard-0101.06 for defining protection against military small arms, specifications should state a product classified as Type III (7.62mm x 5 shots) or Type IV.

All products rated under the U.S. Department of State standard SD-STD-01.01 have been tested against penetration by military small arms and shotguns.[xxiv] The SD-STD-01.01 test procedure involves a minimum of nine shots by 5.56mm, 7.62x51mm, and 12 gauge buckshot in sequence against different target locations.

Outside North America, EN 1063 is one of the most common standards for rating bullet-resistant materials.[xxv] EN 1063 uses a seven-tiered scale to define ballistic protection from projectile weapons (BR classes) ranging from .22 cal. long rifle to 7.62x51mm hardcore ammunition and two additional levels to define protection against shotguns (SG class). Specimens rated under EN 1063 must resist penetration by three shots according to the standard’s test requirements. Under EN 1063, adequate specifications for protection against military small arms are BR5 (5.56mm), BR6 (7.62x51mm), or BR7 (7.62x51mm hard core).

Another European ballistic resistance standard is EN 1522  for windows, doors, shutters and blinds.[xxvi] EN 1522 uses a seven level classification system to describe ballistic resistance by calibers ranging from .22 cal. long rifle to 7.62x51mm hardcore ammunition, and one additional level for 12/70 shotgun. The procedure described in EN 1522 requires that the specimen is subjected to three shots at various target points which are determined based upon the type of product under evaluation. For the purposes of specifying protection against military small arms, appropriate EN 1522 ratings include FB5 (5.56mm), FB6 (5.56mm and 7.62x51mm), and FB7 (7.62x51mm hard core).

The following table compares several common ballistic resistance standards and ratings applicable for protection against military small arms.

Ballistic Standards Chart

Other standards with potential use in specifying ballistic protection requirements in safe room design include:

    • NATO AEP-55 STANAG 4569
    • AS/NZS 2343:1997 Standard

Hold up for a moment…We mentioned 5.56mm, 7.62x51mm (NATO), .30-06 cal, and shotgun, but what about the most popular weapon used by terrorists worldwide–the Kalashnikov (7.62x39mm)?

With the exception of NATO’s STANAG 4569 and provisions for specially testing 7.62x39mm in European standards (e.g., EN 1522, etc.), none of the common standards for bullet-resistant products specifically addresses 7.62x39mm as a test caliber. It is safe to assume products successfully rated for protection against 7.62x51mm will be effective in stopping 7.62x39mm. It is well established that 7.62x51mm has better penetration capability than 7.62x39mm. Therefore, any product rated as/or greater than UL 752 Level 8, ASTM F1233 R3, NIJ Type III, EN 1063 BR6, or EN 1522 FB6 will be adequate for protection against 7.62x39mm weapons.

Many product manufacturers also claim that EN 1063 BR5 and UL 752 Level 7 are effective in resisting 7.62x39mm ball ammunition. Although there are significant differences in the ballistic properties of 5.56x45mm and 7.62x39mm ammunition, there are sources which indicate similar penetration capabilities.[xxvii] However, I recommend requesting documented proof from manufacturers of successful 7.62x39mm testing for EN 1063 BR5 and UL 752 Level 7 products before relying on these rating levels.

Part Three of this article surveys building material components appropriate for safe room construction.

Continued in Part III

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References

[i] Barrier Technology Handbook, SAND77-0777. Sandia Laboratories, 1978.

[ii] Ibid, pp. 16.3-39.

[iii] Critical Intervention Services assisted a window film manufacturer in 2015 in conducting a series of timed penetration tests of unprotected tempered glass windows and glazing reinforced with anti-shatter film. A marketing video produced by the manufacturer displaying a few of these tests is available online: http://www.solargard.com/school-safety/

[iv] SD-STD-01.01, Revision G. Certification Standard. Forced Entry and Ballistic Resistance of Structural Systems. U.S. Department of State, Bureau of Diplomatic Security, Washington, DC, 1993.

[v] ASTM F3038-14, Standard Test Method for Timed Evaluation of Forced-Entry-Resistant Systems, ASTM International, West Conshohocken, PA, 2014

[vi] Manual Forced Entry Standard (MFES) Version 1.0. Centre for the Protection of National Infrastructure (CPNI), N.p.: 2015.

[vii] LPS 1175: Issue 7.2., Requirements and testing procedures for the LPCB approval and listing of intruder resistant building components, strongpoints, security enclosures and free standing  barriers, Loss Prevention Certification Board, Watford, 2014.

[viii] STS 202, Requirements for burglary resistance of construction products including hinged, pivoted, folding or sliding doorsets, windows, curtain walling, security grilles, garage doors and shutters. Warrington Certification Limited, N.p. 2016.

[ix] ASTM F1233-08, Standard Test Method for Security Glazing Materials and Systems. ASTM International, West Conshohocken, PA, 2013.

[x] UL 972, Standard for Burglary Resisting Glazing Material. UL, N.p.: 2006.

[xi] Garcia, Mary Lynn. Vulnerability Assessment of Physical Protection Systems. Elsevier Butterworth-Heinemann, Burlington, MA, 2006.

[xii] EN 1627:2011, Pedestrian doorsets, windows, curtain walling, grilles and shutters. Burglar resistance. Requirements and classification. Brussels: European Committee for Standardization, 2011.

[xiii] EN 1628:2011, Pedestrian doorsets, windows, curtain walling, grilles and shutters. Burglar resistance. Test method for the determination of resistance under static loading. European Committee for Standardization, Brussels, 2011.

[xiv] EN 1629:2011, Pedestrian doorsets, windows, curtain walling, grilles and shutters. Burglar resistance. Test method for the determination of resistance under dynamic loading. European Committee for Standardization, Brussels, 2011.

[xv] EN 1630:2011, Pedestrian doorsets, windows, curtain walling, grilles and shutters. Burglar resistance. Test method for the determination of resistance to manual burglary attempts. European Committee for Standardization, Brussels, 2011.

[xvi] Glass in building. Security glazing. Testing and classification of resistance against manual attack, EN 356:2000. Brussels: European Committee for Standardization, 2000.

[xvii] ANSI/BHMA A156.2, Bored & Preassembled Locks and Latches. Builders Hardware Manufacturers Association (BHMA), New York, NY, 2011.

[xviii] ANSI/BHMA A156.13, Mortise Locks and Latches. Builders Hardware Manufacturers Association (BHMA), New York, NY, 2011.

[xix] UFC 4-023-07, Design To Resist Direct Fire Weapons Effects. US Department of Defense, N.p.: 2008.

[xx] Ibid. pp. 2-1

[xxi] UL 752, Standard for Bullet-Resisting Equipment. UL, N.p.: 2005.

[xxii] ASTM F3038-14, Standard Test Method for Timed Evaluation of Forced-Entry-Resistant Systems, ASTM International, West Conshohocken, PA, 2014

[xxiii] NIJ Standard-0101.06, Ballistic Resistance of Body Armor. U.S. Department of Justice, Office of Justice Programs, National Institute of Justice, Washington, DC, 2008.

[xxiv] SD-STD-01.01, Revision G. Certification Standard. Forced Entry and Ballistic Resistance of Structural Systems. U.S. Department of State, Bureau of Diplomatic Security, Washington, DC, 1993.

[xxv] EN 1063:2000, Glass in building – Security glazing – Testing and classification of resistance against bullet attack. European Committee for Standardization, Brussels, 2000.

[xxvi] EN 1522:1999, Windows, doors, shutters and blinds. Bullet resistance. Requirements and classification. European Committee for Standardization, Brussels, 1999.

[xxvii] “5.56×45 versus 7.62×39 – Cartridge Comparison.” SWGGUN. SWGGUN, N.p. https://www.swggun.org/5-56-vs-7-62/. Accessed 22 Sept. 2017.

Safe Rooms and The Active Shooter Threat (Part I)

By Craig S. Gundry, PSP, cATO, CHS-III

Preceding Note

Few terms in the security industry and emergency management community evoke as many different definitions as the word “Safe Room.” For professionals in the executive protection community, this often means a room engineered to provide significant delay against intrusion by a committed adversary employing advanced tools and entry methods, ballistic protection, and equipped with fire protection and life safety systems, multiple modes of communications, supplies to sustain extended refuge, and similar features. For organizations such as FEMA, the term is often broadly applied to any room or indoor shelter area designed to protect occupants from a hazard (e.g, tornados, outdoor hazardous materials incidents, armed adversaries, outdoor IEDs, etc.). 

In S2’s Anti-Terrorism Officer (ATO) course and my work as a consultant over the past ten years, I also often applied this term with a broad definition when referencing different applications. However, I discovered that vague definition often caused confusion when describing criteria for “safe rooms” appropriate for use in different situations and levels of performance that can be achieved with specific design approaches. A few years ago I started standardizing my use of language to describe different types of safe refuge areas and clarify applicability of prescriptive measures. The terminology I now use is as follows:

    • Safe Room – Room specifically designated and/or designed to provide protection of occupants against armed adversaries.
    • Bomb Shelter Area – Indoor location designated and/or designed to provide protection of occupants against outdoor explosive threats (e.g., suspected VBIEDs, etc.)
    • Shelter-In-Place Room – Indoor room designated and/or designed to minimize air exchange during outdoor airborne hazardous materials events (e.g., toxic industrial chemical accident, vapor or aerosol CB attack, radiological attack, etc.)
    • Severe Weather Shelter Area – Indoor location designated and/or designed to provide protection of building occupants during outdoor weather emergencies (e.g., tornados, hurricanes, sudden severe storms, etc.)

The importance of clear terminology is more than simply a matter of semantics. As a consultant, I spend considerable time reviewing emergency action plans for clients. I frequently encounter plans that universally use the term “safe room” or “shelter area” for multiple types of emergency situations without careful consideration for the unique requirements of each different application. Quite often shelter areas appropriate for use during severe weather are not optimal (or even minimally suitable) for use during outdoor hazardous materials events, and so on.

Many US Government publications provide a starting point in establishing design criteria for safe refuge areas for specific situations. Some of these manuals include FEMA 543, FEMA 428, FEMA P-361, FEMA P-431, UFC 4-023-10, UFC 4-024-01, UFC 4-010-03, and EPA-400/R-17/001.[i][ii][iii][iv][v][vi][vii][viii] Although these manuals provide quite a bit of useful information, the measures they prescribe in some cases are limited in depth or outside the practical reach of many private organizations (and many government clients I have worked with internationally too). For most organizations outside the well-funded US Government community, compromises are often necessary that reconcile risk reduction goals with real world budget and operational constraints. 

In this upcoming series of articles, I will describe my approach to this problem and survey different levels of protection, risk considerations, design rationale, and specifications to achieve different optional levels of performance. 

The first article in this series focuses on safe rooms for use in providing building occupants with protection during armed intrusion events (e.g., active shooter events, terrorist armed assaults, etc.). The design strategies and physical security principles outlined in this article are applicable to all facilities concerned about active shooter attacks including government and commercial office buildings, schools, hotels, community centers, etc. In upcoming articles I will address practical considerations for planning and designing refuge areas for other types of emergency events.

Due to the length of the articles, we will be dividing each article into parts and separate posts. 

Safe Rooms and The Active Shooter Threat

Most organizations concerned about active shooter attacks have adopted the US Department of Homeland Security’s Run-Hide-Fight doctrine or variations promoted by the U.K. and other governments (Run-Hide-Report) as the basis for designing facility emergency action plans and training employees. This simplified response guidance is designed to be regarded as a prioritized list of preferred protective responses when an active shooter attack is recognized. “Run,” for instance, should always be the first option when the opportunity is present. If “Run” is not possible, then “Hide” is the next prioritized option. 

Although “Run” is generally the most preferred response, there are circumstances where “Hide” may be a necessary default action owing to the impracticality of rapidly evacuating a group of people unable to take actions for their own personal safety such as kindergarten students or nursing home residents. Additionally, there are many situations where attempting escape may be more dangerous than simply remaining in place. A good example is a multi-story building when an attack is launched at ground level. Rarely during attacks do people in the “hot zone” have accurate and real-time knowledge of the attacker’s location and safe routes of escape. In this situation, trying to evacuate through lower levels of the building where possible massacre is in progress may be far more dangerous than barricading in a nearby safe location. 

In recent years, DHS has modified its presentation of active shooter education with more detailed guidance about circumstances that warrant a preferred response. Although “Run-Hide-Fight” is easy for the public to remember, the simplified terminology used in the original DHS awareness campaign could result in unsafe actions in some cases. “Hide,” for instance, is vague and implies no other essential protection than concealment. In our seminars and employee training programs, we use the term “Barricade” which we believe describes the recommended action more clearly. Simply put, hiding should never be regarded as a safe action unless the location provides adequate protection against forced intrusion.

Implementation of active shooter response actions should be supported by effective facility infrastructure, physical security, and life safety design. One of the most basic facility preparations is ensuring adequate availability of safe rooms for people to take refuge if escape is not feasible. For this purpose, safe rooms should be identified or designed capable of providing adequate delay against forced entry considering the methods and tools likely to be employed by attackers and, if risk-justified and cost-feasible, ballistic protection against gunfire through walls, glazing, and doors.

So how much delay is necessary for a safe room to be considered “safe?”

The U.S. Department of Defense’s Unified Facilities Criteria UFC 4-023-10 answers this simply: “For the Forced Entry tactic, specify the required protection time based on the response time of the security forces determined in security forces evaluation in addition to the DBT [Design Basis Threat] and the LOP [Level of Protection].”[ix]

Simply stated, a safe room should delay an adversary from forced entry into the room long enough to allow the response force to intervene and neutralize the adversary. The necessary delay time being determined by the response force time and the methods and tools likely to be used by the adversary in penetrating the room.

From the perspective of performance-based physical security design, this is the correct answer and should be the ideal objective. However, implementing this approach properly requires first having a reliable and accurate response force time. If the facility does not have an armed response force on-site, establishing an effective delay time specification based on the expected response times of off-site police or government security forces can be quite difficult. Unless we have a reliable base of reference data from previous and similar emergency dispatches in the local area, the best guidelines we have for estimating response times for off-site police and government security forces may be derived from research studies of previous active shooter attacks:

    • In an FBI-published analysis of 51 active shooter events in the US between 2000 and 2012 where data on response times was available, police response times ranged between 0-15 minutes with a median response time of 3 minutes.[x] However, this analysis does not necessarily describe the true Effective Response Time. I define Effective Response Time as the total time from commencement of the attack and subsequent emergency notification to the time that the security or police forces located and neutralized the perpetrator. For example, at Sandy Hook Elementary School, police officers arrived on scene at 09:37 (~2.5 minutes after the first 911 call and only 3-4 minutes after Adam Lanza opened fire). However, officers did not tactically clear the building and arrive at Lanza’s location until 09:44 (~4 minutes after Lanza committed suicide).[xi] In many incidents we’ve case studied over the past several years, the police dispatch and arrival times aligned with the findings of the FBI analysis, but there was at least an additional 2-5 minutes of time before officers made entry and located the attacker.
Previous Active Shooter Events Timelines
    • As part of the incident data collection process during Purdue University’s 2014 Mitigating Active Shooter Impact study, researchers collected information about response times related to 24 school shootings and 41 workplace shootings in the United States. The report describes: “The fastest police response time noted in these events was 5 to 6 minutes, with most taking much longer.”[xii]

Based on information from these two studies, a safe room delay time goal in the United States with realistic expectation of off-site police intervention would be between 5 and 10 minutes.

A more cautious approach would also consider the possibility of an event escalating into a siege by police upon arrival and thus further delayed intervention. In 2015, Critical Intervention Services conducted a short study of 20 terrorist active shooter/MTFA attacks with the intention of creating an empirical and research supported justification for establishing Design Basis Threat (DBT) capabilities.[xiii] Although the sample size was small, the results did yield some useful points to consider.

In the CIS study, 35% of all attacks escalated into a siege by police/security forces upon arrival. In a number of these incidents, intervention was delayed due to early confusion about the event (“hostage situation” versus “armed massacre”). Some events resulted in a siege when arriving police or security forces were overwhelmed by the adversary’s firepower and withdrew pending the arrival of more assistance. In other events, police and security forces made committed entry, but the size of the facility and movement of the attackers inside the building delayed location and neutralization of the adversaries (e.g., 2013 Washington Navy Yard, etc.).

Incidents documented in the CIS study that escalated into a siege had a duration ranging between 2h 24m and est. 96 hours, with a mean duration of 21h 44m. Although most events resulting in siege durations over 2 hours were in Africa or West Asia, recent incidents have occurred in Western countries with effective response times over 2 hours such as the 2016 Pulse Nightclub shooting (194 minutes from first call to 911) and Bataclan Theater (~156 minutes from first call to 112).[xiv][xv][xvi]

Adversary Behavior and Capabilities: Adopting a rational and research supported approach to threat definition

The delay time provided by safe room barriers (e.g., doors, locks, glazing, etc.) is directly related to the tools and methods adversaries use to breach our barriers. Of the sample set assessed during our 2015 study of terrorist armed attacks, in none of the events documented did adversaries arrive equipped with tools (other than firearms) for the specific purpose of penetrating barriers. In case research conducted by CIS about other armed attacks against facilities over the past 20 years, the number of incidents where adversaries brought tools specifically for forced entry purposes was few. In the majority of attacks, forced entry was facilitated exclusively by blunt object impact (e.g., kicking, beating with rifle butt stock, etc.) and sometimes aided by bullet penetration or cutting with a bladed weapon.

Another issue worth considering is adversary effort and commitment to attack people located inside locked rooms. As described previously, optimal safe room designs specify delay time objectives based on the expected effective response time of police or on-site security forces. However, in some situations, simply providing enough delay to frustrate adversary attempts to gain entry may be a justifiable and practical compromise. Joseph Smith and Daniel Renfroe describe their observations on this matter in an article on the World Building Design Guide web site: Analysis of footage from actual active shooter events have shown that the shooter will likely not spend significant time trying to get through a particular door if it is locked or blocked. Rather, they move to their next target. They know law enforcement is on its way and that time is limited. [xvii]

Separate case research conducted by Critical Intervention Services also supports Smith and Renfroe’s perspective. In a large percentage of attacks, adversaries focus solely on targets of easiest opportunity by using visually-obvious pathways and unlocked/unobstructed portals (e.g., doors, windows, etc) to facilitate indoor movement. This behavior may be due to perceived time pressure (“kill as many as possible before the police arrive”) or possibly diminished problem-solving ability resulting from activation of the Sympathetic Nervous System (SNS). In most documented attacks where adversaries committed effort to forcibly enter locked rooms, intervention by police or security forces was delayed and adversaries had exhausted all targets in accessible areas. 

An effective DBT or ‘Threat Definition’ for physical security design purposes should also consider the number of potential adversaries and likely weapons. The number of attackers has a direct relationship to the potential effectiveness of our expected response force (Probability of Neutralization) and may also influence the likelihood of adversaries forcibly entering secured rooms to locate targets. Many documented incidents where attackers forcibly entered locked rooms to seek targets involved more than one perpetrator.[xviii] Weaponry also influences the potential effectiveness of our response force, and caliber and type of ammunition determines the effectiveness of safe room barriers in resisting ballistic penetration.

In the United States, the spectrum of active shooter adversaries has historically been diverse with most attacks committed by non-ideologically motivated perpetrators in alignment with Dr. Park Dietz’s definition of a “pseudocommando.”[xix] The overwhelming majority of these attacks to date have been executed by a single attacker withstanding a handful of notable exceptions (e.g., 1998 Westside Middle School, 1999 Columbine High School, 2011 South Jamaica House Party, and 2012 Tulsa).[xx] Additionally, most terrorist-related armed attacks in the United States to date also involved only one perpetrator with exceptions including the 2015 San Bernardino and 2015 Curtis Culwell Center attacks. According to FBI statistics, handguns were the most powerful firearm used in most attacks (59%) with rifles constituting 26% of incidents.[xxi] Although the FBI has not published statistics on weapon calibers used in domestic active shooter attacks, most mass casualty attacks where rifles were employed in the U.S. involved 5.56mm weapons with examples including assaults at the Pulse Nightclub (2016), Inland Regional Center (2015), Sandy Hook Elementary School (2013), and Aurora Century 16 Theater (2012).

Regional trends in adversary characteristics vary greatly in different parts of the world. In locations where terrorist attacks are more frequent than non-ideological targeted violence, the number of perpetrators in attacks is often higher and 7.62x39mm weapons (AK-47) have been most common. According to the Critical Intervention Services 2015 MTFA study, 1-2 perpetrators was most common in terrorist firearms attacks in Europe with notable exceptions being events such as the 13 November Paris attacks.[xxii] In Africa, by contrast, terrorist groups such as Al-Shabaab frequently use teams of 4-9 attackers in assaults on civilian locations such as the Westgate Shopping Mall (2013), Garissa University (2015), and numerous hotels in Mogadishu.[xxiii] Al-Shahbab’s modus operandi has often been quite advanced and often employs disguise, distraction, or IEDs to breach outer protective layers of target facilities.

By considering the historical characteristics of adversaries and event dynamics as demonstrated in previous attacks, we can develop a threat definition for safe room design purposes that is rational and justifiable. Following are some examples of reasonable threat definitions appropriate in different circumstances based on historical adversary modus operandi.

By considering the historical characteristics of adversaries and event dynamics as demonstrated in previous attacks, we can develop a threat definition for safe room design purposes that is rational and justifiable. Following are some examples of reasonable threat definitions appropriate in different circumstances based on historical adversary modus operandi.

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Copyright © 2017 by Craig S. Gundry, PSP, cATO, CHS-III

CIS consultants offer a range of services to assist organizations in managing risks of active shooter violence.  Contact us for more information.

References

[i] FEMA 453, Safe Rooms and Shelters: Protecting People Against Terrorist Attacks. FEMA, U.S. Department of Homeland Security, Washington, DC, 2006.

[ii] FEMA 428/BPIS-07, Primer to Design Safe School Projects in Case of Terrorist Attacks and School Shootings. U.S. Department of Homeland Security, Washington, DC, 2012.

[iii] FEMA P-361, Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms. FEMA, U.S. Department of Homeland Security, Washington, DC, 2015.

[iv] FEMA P-431, Tornado Protection: Selecting Refuge Areas in Buildings. FEMA, U.S. Department of Homeland Security, N.p.: 2009.

[v] UFC 4-023-10, Safe Havens. US Department of Defense, N.p., 2010.

[vi] UFC 4-024-01, Security Engineering: Procedures For Designing Airborne Chemical, Biological, And Radiological Protection For Buildings, US Department of Defense, N.p., 2008.

[vii] UFC 4-010-03, Security Engineering: Physical Security Measures For High-Risk Personnel. US Department of Defense, N.p., 2011.

[viii] EPA-400/R-17/001, PAG Manual: Protective Action Guides and Planning Guidance for Radiological Incidents. U.S. Environmental Protection Agency, Washington, DC, 2017.

[ix] UFC 4-023-10, Safe Havens. US Department of Defense, N.p.: 2010. pp. 11.

[x] Blair, J. Pete, Martaindale, M. Hunter, and Nichols, Terry. “Active Shooter Events from 2002 to 2012.” FBI Law Enforcement Bulletin. Federal Bureau of Investigation, 1 July 2014, https://leb.fbi.gov/2014/january/active-shooter-events-from-2000-to-2012. Accessed 22 Sept. 2017.

[xi] Report of the State’s Attorney for the Judicial District of Danbury on the Shootings at Sandy Hook Elementary School and 36 Yogananda Street, Newtown, Connecticut on December 14, 2012. Office Of The State’s Attorney Judicial District Of Danbury, Stephen J. Sedensky III, State’s Attorney, N.p., 25 November 2013

[xii] Anklam, Charles, Adam Kirby, Filipo Sharevski, and J. Eric Dietz. “Mitigating Active Shooter Impact: Analysis for Policy Options Based on Agent/computer-based Modeling.” Journal of Emergency Management 13.3 (2014): 201-16. Web.

[xiii] Gundry, Craig S. “Analysis of 20 Marauding Terrorist Firearm Attacks.” Preparing for Active Shooter Events. ASIS Europe 2017, 30 Mar. 2017, Milan, Italy. (Presentation included results of an unpublished 2015 study by Critical Intervention Services. As of August 2017, an improved study is underway addressing a wider spectrum of data points and larger sample set. The results of the new study (ASAD – Active Shooter Attack Dynamics Study) will be published when complete. For information about the ASAD Study, visit: https://www.linkedin.com/pulse/asad-study-team-needs-your-assistance-gundry-psp-cato-chs-iii/)

[xiv] Lotan, Gal Tziperman, Minshew, Charles, Lafferty, Mike, and Gibson, Andrew. “Orlando nightclub shooting timeline: Four hours of terror unfold.” Orlando Sentinel, 31 May 2017, http://www.orlandosentinel.com/news/pulse-orlando-nightclub-shooting/os-orlando-pulse-nightclub-shooting-timeline-htmlstory.html. Accessed 22 September 2017.

[xv] “What happened at the Bataclan?” BBC News, 9 December 2015, http://www.bbc.com/news/world-europe-34827497. Accessed 22 September 2017.

[xvi] Aubourg, Lucie. “Terror in Paris: This Is What Happened at the Bataclan Concert Hall During the Paris Attacks.” Vice News, 25 November 2015, https://news.vice.com/article/this-is-what-happened-at-the-bataclan-concert-hall-during-the-paris-attacks. Accessed 22 September 2017.

[xvii] Smith, Joseph, and Daniel Renfroe. “Active Shooter: Is There a Role for Protective Design?” World Building Design Guide, National Institute of Building Sciences, 2 Aug. 2016, www.wbdg.org/resources/active-shooter-there-role-protective-design. Accessed 22 Sept. 2017.

[xviii] Examples including the 2008 Taj Majal attack and a hotel in North Africa [details confidential].

[xix] Dietz, Park D. “Mass, Serial, and Sensational Homicides.” Bulletin of the New York Academy of Medicine.  62:49-91. 1986.

[xx] Blair, J. Pete, and Schweit, Katherine W. A Study of Active Shooter Incidents, 2000 – 2013. Texas State University and Federal Bureau of Investigation, U.S. Department of Justice, Washington D.C. 2014. pp. 7. PDF. (The 2011 South Jamaica and 2012 Tulsa shootings are specifically noted as the only events involving more than one attacker in the FBI’s study of U.S. domestic active shooter attacks between 2000 and 2013.)

[xxi] Blair, J. Pete, Martaindale, M. Hunter, and Nichols, Terry. “Active Shooter Events from 2002 to 2012.” FBI Law Enforcement Bulletin. Federal Bureau of Investigation, 1 July 2014, https://leb.fbi.gov/2014/january/active-shooter-events-from-2000-to-2012. Accessed 22 Sept. 2017.

[xxii] Gundry, Craig S. “Analysis of 20 Marauding Terrorist Firearm Attacks.” Preparing for Active Shooter Events. ASIS Europe 2017, 30 Mar. 2017, Milan, Italy.

[xxiii] Gundry, Craig S. “Threat Assessment Methodology and Development of Design Basis Threats.” Assessing Terrorism Related Risk Workshop. S2 Safety & Intelligence Institute, 25 Apr. 2017, Brussels, Belgium.