Testing and specifications: Aluminum-framed fenestration assemblies

by arslan_ahmed | October 21, 2022 10:00 am

Understanding their role in active shooter attacks

By Marc Donahue, EFCO

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Parents, school officials, teachers, staff, and facility managers are increasingly asking architects and specification professionals whether their buildings are taking all the precautions available to mitigate shooting incidents. While no building product component or system is truly “bulletproof,” industry resources are evolving to evaluate, select, and specify high-performance, aluminum-framed curtain wall, storefront, entrance, and window systems which can help protect against active shooter attacks in schools, universities, and other facilities.

Based on real-life data and analytics, the Shooter Attack Test Method describes one rigorous ballistic and impact test regimen for whole product assemblies.

School shootings statistics

The K-12 School Shooting Database¹ project is researched and maintained as part of the Advanced Thinking in Homeland Security (HSx) program at the Naval Postgraduate School’s Center for Homeland Defense and Security (CHDS). The database documents when a gun is brandished, fired, or a bullet hits school property for any reason, regardless of the number of victims, time of day, or day of the week. A subset of school shootings, a “school active shooter attack” refers to when one or more individuals are actively engaged in killing or attempting to kill people in a confined, populated area.

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The CHDS data currently lists over 2000 total school shooting incidents from 1970 to present. More than 160 of these incidents meet the definition of a school active shooter attack.

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The National Safety Security Protection Association (NSSPA) is a nonprofit organization focused on K-12 schools. Its all-volunteer membership includes subject matter experts in active shooter attacks, physical security, counter terrorism, building codes, architecture, education, psychology, engineering, and security technology. NSSPA² analyzed data from 1985 to 2019 data, using CHDS and Education Week’s School Shooting Tracker.³ According to the data, on average, a school shooting occurred every eight school days, lasted eight minutes (without hostages), during which, someone was shot every 60 seconds. These events typically involved only one shooter with a preplanned attack. Further, additional research observed how 25 percent of active shooter attacks in educational settings involved two to five shots fired.

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The report also stated the majority of active shooter attacks occurred during the school day (93 percent) and inside a building (80 percent), with most taking place in hallways (24 percent), classrooms (21 percent), and cafeterias (13 percent). Though most attacks occurred inside a building, 20 percent were outside. Some of these involved the perpetrator shooting at windows and entrances to gain access.

Out of the active shooter incidents where gunfire struck a school’s entrance or window, 35 struck an exterior window, 12 struck an entry point, and 11 struck an interior window opening. There are more than 30 examples since 1985 of shooters gaining access to school buildings and interior rooms by shooting at windows, doors, and other whole fenestration product assemblies.

Preventative measures

Alarm systems, security cameras, and other technology help to deter, detect, and distract a potential risk, and quickly alert emergency responders. When these deterrents fail, physical barriers are the first line of defense. Windows, doors, and fenestration systems offer transparency to see and assess the risk, but with an active shooter, ground-level glass also can become the first target.

The Whole Building Design Guide (WBDG) resources on active shooter protective design⁴ notes, “Ultimately, there are two options: impede the shooter or impede the bullet.” Further, it states, “Since most active shooter events generally last only minutes, access denial can be an effective way to mitigate potential losses. Slowing or delaying an aggressor by just a minute or seconds may give law enforcement time to arrive before mass casualties are incurred.”

The WBDG acknowledges how specifying fenestration product assemblies similar to those in high-security courthouses and embassies “is often not practical, cost-effective, or even desired” for schools. “Analysis of footage from actual active shooter events have shown the shooter will likely not spend significant time trying to get through a particular door if it is locked or blocked,” continued the WBDG. “Rather they move to their next target. They know law enforcement is on its way and their time is limited.”

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Given “the current architectural preference for large amounts of glazing to provide natural light into spaces,” the WBDG recommends where windows are present, “they contain laminated glass which provides some resistance to ballistics attack and forced entry.” It adds, “some level of protective glazing, especially for windows and doors near lobbies and other entrances offer a potential area where simple improvements can provide significant benefit.”

The WBDG also cautioned, “The lack of guidance documents focusing specifically on active shooter designs will likely lead to varying levels of implementation and reliance on methods and technologies which may not be as effective or cost efficient.”

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Some existing standards, industry guidelines, and technical papers pertaining to security performance of windows, entrances, other fenestration products assemblies, and key components include:

• UL 752 (edition 11) Standard for Bullet-Resisting Equipment
• National Institute of Justice (NIJ) Standard 0108.01 Ballistic Resistant Protective MaterialsAmerican Society for Testing and Materials (ASTM International)

• ASTM E2395-21 Standard Specification for Voluntary Security Performance of Window and Door Assemblies with Glazing Impact
• ASTM F476-14 Standard Test Methods for Security of Swinging Door Assemblies
• ASTM F588-17 Standard Test Methods for Measuring the Forced Entry Resistance of Window Assemblies, Excluding Glazing Impact
• ASTM F1233-21 Standard Test Method for Security Glazing Materials and Systems
• ASTM F3038-21 Standard Test Method for Timed Evaluation of Forced-Entry-Resistant Systems
• American National Standards Institute, ANSI Z97.1-2015 For safety glazing materials used in buildings – safety performance specifications and methods of test
• Federal Emergency Management Agency, FEMA 428 (2004) Primer to Design Safe School Projects in Case of Terrorist Attacks
• National Fire Protection Association, NFPA 3000® (edition 2021) Standard for an Active Shooter/Hostile Event Response (ASHER) Program

National Glass Association (NGA) Glass Technical
Papers (GTPs)

• FB16-07 Bullet Resistant Glazing
• FB43-14 (2020) Security Glazing
• FB71-21 School Security Glazing

As a reminder, the NGA’s 2021 School Security Glazing technical paper FB71-21⁵ observes, “There are no building codes or mandates for school security. In comparison, every building is subject to fire codes because of (relatively smaller numbers of) historic deaths in building fires. Since the adoption and enforcement of the fire codes, the number of deaths from fires has dramatically decreased.”

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New test methods and emerging standards

Those seeking design-conscious, cost-effective, high-performance, fenestration systems to mitigate active shooter attacks must consider the entire assembly in the context of its project application.

Design and specification professionals understand they should be skeptical of any claim offering a “bulletproof” solution. The goal is to slow down attackers, giving the people inside more time to react, and for emergency response teams to arrive at the scene and defuse the situation.

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Glass and glazing

There are many test standards available to determine glass specification requirements for life-safety applications. Glass can be specified for bullet resistance, and window film added to glass may enhance its ballistic properties.

Keep in mind, most glass safety films were initially made for solar control and converted to vandal resistance. Only one applied film is recognized as tested to resist active shooter attack incidents when applied to 6.53 mm (0.250 in.) tempered glass. This 23-mil-thick film’s properties feature a break strength of 0.0044 kPa (0.00063816604723 psi).⁶

There are many laminated, insulating glazing units tested to mitigate blast hazards and ballistic attacks. These units may be enhanced with low-e, solar reflective, or tinted coatings to achieve a project’s energy efficiency and aesthetic design intentions. Some also may be specified for fire ratings, hurricane impact resistance, noise reduction, and other performance requirements. While the glass is significant, it is only one component of a whole fenestration product assembly.

Aluminum framing

The glazing units of a complete fenestration assembly are secured on all sides by the framing members. In schools, universities, and other educational, institutional and commercial buildings, extruded aluminum is the framing material of choice.

Aluminum is versatile in its fabrication and installation. It can be shaped into rectilinear or curvilinear forms in almost any size. It can be finished in durable anodized tones which highlights its metallic properties, painted in nearly any color, or coated to resemble natural wood, terracotta, or stone.

Since aluminum is a conductive material, the extruded metal’s interior and exterior surfaces must be separated to minimize thermal bridging. Thermally “breaking” and insulating the frame allows whole fenestration assemblies
to meet condensation resistance goals, model energy codes, and other project-specific requirements. For high-security performance objectives, aluminum framing may be reinforced with steel for additional rigidity and strength.⁷

Aluminum has a long lifespan and is low maintenance, making it an economical option for many school districts and college campuses. It is also considered a sustainable material choice. Framing components also can be manufactured with recycled aluminum content. At the end of its useful life, the metal once again can be recycled.

Shooter Attack Test Method

Educational project specifications may now reference the Shooter Attack Test Method for windows, doors, and other fenestration assemblies. Developed by subject matter experts and recommended by the NSSPA, this rigorous, engineered process tests a whole product assembly’s ability to delay an attacker with a gun.

Shooter Attack Test Method⁸ criteria are based on real-life data and analytics of shooter attack incidents. Improving upon existing industry standards, it is the only test to add ballistic testing immediately prior to impact testing. First, the glass is shot 10 times with an AR15 using .223 rounds. The glass is then struck twice with a 45.4 kg (100 lbs) ram at 67.8 Nm (50 ft/lb).

If the ram penetrates the glass before the completion of the two hits, it is considered a failure. If the ram does not penetrate the glass after two hits, impact force is continually increased until a breach occurs. The tested specimen realistically demonstrates how the whole product assembly would perform if an active shooter were to shoot and then use bodyweight or an object to apply force to the compromised glass surface.

The Shooter Attack Test is conducted by a qualified laboratory. Fenestration assemblies which successfully pass the test criteria are recommended by the NSSPA. Tested assemblies for shooter attack applications provide consistent and repeatable performance, similar to other safety-critical applications.

Recognizing the need for an improved shooter attack test method, a new ASTM standard⁹ currently is being finalized. Test Method for Forced-Entry-Resistance of Fenestration Systems after Simulated Active Shooter Attack will provide the minimum industry-accepted standard for security glazing in schools. The new standard’s procedures follow the Shooter Attack Test methodology, where the product assembly is subjected to multiple shots by a single gun, followed by a forced-entry impact on the weakened glass.

The standard was initiated in November 2021 and the most recent ballot was issued in March 2022. It is now pending successful full ASTM International society review prior to publication.

If no objections are raised, the complete and published ASTM standard is expected to be available before the end of 2022.

According to ASTM, “Tested systems will be able to provide precious resistance to entry allowing precious moments for notifications, warnings and protective exercises to be launched within a facility, thus potentially save lives and reduce injuries. The method offered is based primarily on previously published ASTM security standards which have been brought together to provide a single, repeatable, mechanically driven, simple-to-execute and easily reference-able standard… It should be noted how the glazing, when tested alone, cannot achieve a level rating per this standard as it has not been tested in a system.”

The new standard will likely provide eight rating levels (expected to be published) corresponding with the level of applied force.¹⁰ While intended for use by schools, the ASTM standard is not restricted to educational facility applications.

Also in anticipation of the new standard, several fenestration products have met the requirements of the Shooter Attack Test Method and are now available for specification and installation. These include aluminum-framed curtain wall, storefront, entrance, and window systems.

Developed by enhancing existing whole fenestration product assemblies, these tested products offer visual flexibility, sustainability, longevity, availability, competitive pricing, and warranties which are comparable to other high-performance products on the market. Since these products look like they are already in use, they may be perceived by an active shooter as a as a weak target to gain access into the building’s interior—when they are actually delaying entry.

Products which have been successfully tested using method will also be familiar to glazing contractors. These aluminum-framed fenestration assemblies follow the same glazing methods. They use the same equipment and installation techniques, requiring similar labor and time as commercial systems. Experienced glazing contractors will find it straightforward to retrofit and replace earlier fenestration systems with newer assemblies which have passed the Shooter Attack Test Method.

Conclusion

Modern educational facilities can be designed, specified, and constructed with large fenestration assemblies and glass expanses which maximize aesthetics, daylighting, and views, while addressing multiple performance requirements. Adding to buildings’ occupant safety goals, shooter attack-resistant performance requirements now also should be considered when selecting fenestration assemblies.

Specifying aluminum-framed curtain wall, storefront, entrance, and window systems verified to meet the Shooter Attack Test Method improves the available protection within schools, colleges, universities, and other learning centers.   cs

Author’s note: Sample specification

Building on previously approved specification language for high-performance whole fenestration product assemblies, here is a sample of selected text for aluminum-framed entrances and storefront systems for projects with active shooter attack requirements:¹⁰

This selected text is intended only as an example. The language will vary depending on the specified system and the project’s requirements. Please work with the building team and product manufacturer to determine appropriate and complete language.

This interim language is recommended by the author for use pending finalization of the ASTM Test Method for Forced Entry Resistance of Fenestration Systems after Simulated Active Shooter Attack, currently Work Item ASTM WK78966.

PART 1–GENERAL

1.05   Laboratory Testing and Performance Requirements

1. Test Procedures and Performance
2. FTD-SA–Filti Testing and Development, Standard for Shooter Attack

PART 2–PRODUCTS

2.01   Materials

A. Aluminum

1. 1. Extruded aluminum shall be 6063-T6 alloy and temper.

B.Shooter Attack Assembly Testing

1. 1. Products will be tested as a whole system, including doors, framing, and glass.
   2. Testing shall consist of a two-part test method. Part 1 requires the glass and door to be shot with an AR-15 .223 rifle: eight shots at the glass in a 457.2 mm (18 in.) diameter from center, with two additional shots 50.8 mm (2 in.) left and right of the center of the glass, for a total of 10 shots at the glass. There will also be four additional shots within a 228.6-mm (9-in.) diameter circle around the lock mechanism. One additional shot at the center of the lock, totaling five shots at the lock.
   3. Part 2 of the test method is to apply force to the complete assembly after the glass has been weakened by the shot sequence in Part 1. The force applied begins at 67.8 Nm (50 ft/lb) of energy and then increases in increments of 67.8 Nm (50 ft/lb). Each increase is assigned a class number.
   4. Complete assembly must successfully withstand a Class 5 shooter attack.
   5. Failure occurs when any part of the specimen fails, allowing an intruder to gain entry.

Potential energy of impactor and drop height for various levels of attack

Class	Potential Energy		Height of Drop
	J	ft*lbf	mm	ft
1	68	50	152	0.5
2	136	100	305	1.0
3	203	150	457	1.5
4	271	200	610	2.0
5	339	250	762	2.5
6	407	300	914	3.0
7	475	350	1067	3.5
8	542	400	1219	4.0

 

C. Glass

A complete glass description is required for the manufacturer to supply appropriate glazing gaskets
even if glass and glazing is by others. Follow local building codes regarding safety glass.

Glass to be 25.4 mm (1 in.) Insulating glazing unit to meet FTD-SA Class 5 constructed as follows:

a. [product name] Shooter Attack rated by [manufacturer name]

b. Exterior lite – ___ thick, ___ color, ___ glass (annealed, heat-strengthened, tempered), with a surface coating of ___ on the #2 surface.

c. Air space of ___ mm (inch) [or argon filled].

d. Interior lite – [product name] Shooter Attack rated by [manufacturer name]

OR

Glass to be Laminated Monolithic to Meet FTD-SA Class 5 constructed as follows:

a. 7.9 mm (0.3125 in.) [product name] Shooter Attack rated by [manufacturer name]

Notes

¹ See K-12 School Shooting Database; Advanced Thinking in Homeland Security (HSx) program at the Naval Postgraduate School’s Center for Homeland Defense and Security (CHDS), Monterey, California; accessed June 11, 2022; https://www.chds.us/ssdb/[9].

² Refer to 2019 National Safety Security Protection Association (NSSPA) K-12 Active Shooter Study; accessed June 11, 2022; https://nsspa.org/statistics/2019-nsspa-k-12-active-shooter-study/[10].

³ See Education Week’s 2022 School Shooting Tracker; accessed June 9, 2022; https://www.edweek.org/leadership/school-shootings-this-year-how-many-and-where/2022/01[11].

⁴ Read “Active Shooter: A Role for Protective Design;” Whole Building Design Guide (WBDG); Joseph L. Smith, PSP and Daniel R. Renfroe, PSP, Applied Research Associates, Inc.; updated April 30, 2021; https://www.wbdg.org/resources/active-shooter-role-protective-design[12].

⁵ Read “School Security Glazing” FB71-21 Glass Technical Paper; National Glass Association (NGA) Technical Services Division; published Feb. 2021; available for purchase at https://members.glass.org/cvweb/cgi-bin/msascartdll.dll/ProductInfo?productcd=SCHOOLSECURITY[13].

⁶ See Armoured One; accessed June 11, 2022; https://armouredone.com/[14].

⁷ Refer to Intertek and Architectural Testing Inc. (ATI), Report No. G8684.01-119-12 Ballistics Performance Test, EFCO 5600 Series Aluminum Window Frame.

⁸ Refer to Shooter Attack Certification Testing; Filti Testing & Development; accessed June 11, 2022; https://filtitd.com/services/shooter-attack-certified-testing/[15].

⁹ Read “New Test Method for Forced-Entry-Resistant of Fenestration Systems after Simulated Active Shooter Attack,” Work Item ASTM WK78966; ASTM International, subcommittee F12.10; accessed June 12, 2022; https://www.astm.org/workitem-wk78966[16].

¹⁰ Read “Passing the Test: ASTM Develops Forced-Entry Security Standard,” USGlass Metal & Glazing; Julia Schimmelpenningh, Eastman Chemical Co. and ASTM WK78966 technical contact; published May 2022; https://www.usglassmag.com/2022/05/the-guestbook-may-2022/[17].

¹¹ See EFCO; accessed June 2022; https://efcocorp.com/[18].

Author

Marc Donahue is the director of agency partners’ programs at EFCO. He leads the team working in partnership with Armoured One to develop the industry’s first complete fenestration assemblies to successfully pass the Shooter Attack Test Method. Donahue can be reached at mdonahue@efcocorp.com.

Source URL: https://www.constructionspecifier.com/testing-and-specifications-aluminum-framed-fenestration-assemblies/

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