Through the window: Security glass magnified

A school cafeteria’s exterior appearance provides no hints that the glazing system employed in this project actually has security glass.
A school cafeteria’s exterior appearance provides no hints that the glazing system employed in this project actually has security glass.

HPW updated this protocol three times between 1983 and 2003, with the current standard referred to as HPW-TP-0500.03. A number of changes, deletions, and additions have occurred to this test throughout the three updates, such as:

  • added the employment of handheld saws and alternative chemicals;
  • amended use of the sledgehammer and crowbar;
  • reformatting and rewording of the document;
  • deleting reference to a ballistic test requirement; and
  • removing the term for tested ‘assemblies’ as focus was placed solely on the glass.

ASTM test procedures

Strikingly similar to HPW-TP-0500.03 is ASTM F1233. It was first published in 1998 and has since had three revisions, the latest being in 2013. Both tests are class/step based (i.e. the ‘attackers’ take breaks between each step) and undergo five types of threats, such as ballistics (not required because the test report will either show results for bullet resistance if this is performed, or it will not mention ballistics

at all if the glass is not shot), blunt and sharp tools impact, thermal stress, and chemical deterioration, depending on how many steps a product lasts until failure. As these tests are designed for products used in correctional/jail settings, the person meant to be contained will never have a firearm and is not pertinent to the testing.

Lastly, these two test methods default to the same installation for setup where the steel glazing stop will be “oriented to support the entire periphery of the protected face of the distance of the sample for a distance of 25 mm (1 in.) from its edge.” This is important because standard commercial glazing systems, such as aluminum doors, storefronts and/or curtain walls, along with FRP and hollow metal doors and framing are unable to meet the 25-mm distance requirement, thus rendering these test methods as non-applicable for commercial installations.

ASTM F1233 allows glass and framing product manufactures to test the glazing system based on their recommendations. A company can test using a specific system if they desire, however, it is unlikely that system will be stronger than the default welded steel detention-like framing. When a specification is written, the only item listed referencing ASTM F1233 is the test itself and the class/level to be met. The door or framing the glazing is tested in is rarely, if ever, mentioned alongside the test. Hence, glass manufacturers test use the detention-style framing.

Using the same test setup with its 25-mm edge bite is ASTM F1915, Standard Test Methods for Glazing for Detention Facilities. This test method has four levels where the glazing is subject to an equal number of impacts from both the blunt and sharp impactor weights. This mechanical-based test uses weighted impactors on a pendulum where the object swings into the center of the glass pane. Level one is constituted as a 60-minute attack and receives 600 total impacts. Level two is a 40-minute attack and receives 400 total impacts, level three is a 20-minute attack and receives 200 total impacts, and level four is a 10-minute attack and receives 100 total impacts.

In each of these three tests—HPW-TP-0500.03, ASTM F1233, and ASTM F1915—failure occurs when a 203 x 203 x 127-mm (8 x 8 x 5-in.) cuboid, also referred to as ‘body passage,’ passes through the test specimen. Glazing products undertaking these tests are often laminated. In some cases there may
be multiple layers of glass, polycarbonate acrylic, or a combination of these materials. Thicknesses and weights are based on the product and the class or grade a manufacturer is looking to meet. These can be anything from a 10-mm (3/8-in.) polycarbonate at 2 kg (4 lb)/sf, to a 50-mm (2-in.) unit at 7 kg (15 lb)/sf.

5-aa protocols

The 5-aa1, 5-aa5, and 5-aa10 forced entry protocols are the most recent addition to the available lineup of forced entry glass testing methods. These methods require the testing to include all components of an installed glass and glazing system. The 5-aa protocols were created to develop a standard for forced entry glazing in infrastructure applications where 6-mm (¼-in.) monolithic and 25-mm (1-in.) insulated glass are used, the majority of commercial glass applications. Earlier, there was a void in the Division 08–Openings section for combining security with the everyday building because specialty security glass, such as bullet-resistant, detention glazing, blast-resistant glazing, and hurricane glazing, require specific systems to accommodate glass thicknesses and ratings. The 5-aa methods aim to accommodate the different types of security glazing systems—existing or specified—in commercial facilities, thereby not altering the look and alleviating additional costs for specialty doors, frames, and windows.

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