NIJ body armor testing is flawed and does not adequately assess the protective qualities of soft body armor. These problems have been known for quite some time. For example, the U.S. Congress, Office of Technology Assessment (OTA) published “Police Body Armor Standards and Testing”, a two volume critique of NIJ armor testing 16 years ago:
U.S. Congress, Office of Technology Assessment, Police Body Armor Standards and Testing, Volume I, OTA-ISC-534 (Washington, DC: U.S. Government Printing Office, August 1992).
U.S. Congress, Office of Technology Assessment, Police Body Armor Standards and Testing, Volume II: Appendices, OTA-ISC-535 (Washington, DC: U.S. Government Printing Office, September 1992).
During that same time period, several other papers, highly critical of NIJ testing were also published:
Jason, A; Fackler, ML: "Body Armor Standards: A Review and Analysis." Wound Ballistics Review, 1(1), Winter 1991.
Bachner, TE: "The 'V50 Ballistic Limit: A Reliable Test for Body Armor." Wound Ballistics Review, 1(4); pp 20-25, 1994.
MacPherson, D: "Projectile Dynamic Interactions and Associated Body Armor Effects." Wound Ballistics Review, 1(4); pp 29-31, 1994.
MacPherson, D; Fincel, E; Miloskovich, N: "Body Armor Penetration Dynamics." Wound Ballistics Review, 3(2); pp 16-24, 1997.
MacPherson, D: "A body Armor Penetration Rumor." Wound Ballistics Review, 3(4); p 29, 1997.
Unfortunately, NIJ did not make substantial improvements in their methodology over the next decade…
Fast forward to late 2001 and early 2002 when NIJ was informed by several sources that Zylon was exhibiting early degradation and was at risk for penetration--NIJ’s initial response was to pretend there was no problem. Only after several vests were perforated and officers were killed and wounded did NIJ finally begin a S L O W investigation that ultimately led to Zylon’s decertification in the fall of 2005, some four years after the problem was first identified.
Although the Zylon problems are thankfully now behind us, there is another problematic issue that NIJ is also aware of, but has once again failed to address--the ongoing problems associated with polyethelene laminate soft armor, including:
1) Contact shot failures
2) Curling
3) Delamination
4) Stiffness
5) Heat retention
6) Material strength degradation in heat
7) Compression set wrinkling
8) Fiber migration
According to the last batch of data I saw reported from the FBI Uniform Crime Reports, approximately 1/3 of the incidents where officer’s were killed or wounded occurred at contact or near-contact distances. This seems like a fairly high potential for contact shots, yet NIJ inexplicably fails to test for this event. Contact shots can cause extensive damage to polyethelene laminate soft vest materials (Spectra Shield, Gold Flex, Dyneema, etc…) as noted in the photos below:
Contact shots appear to melt polyethelene laminate vest materials and result in large holes in the vests containing polyethelene laminate materials. Even when bullets are stopped, large holes are burned deeply into the polyethelene laminate materials resulting in the vests offering minimal protection against second shots to previously hit areas. In contrast, 100% woven p-aramid vests can withstand contact shots with little damage, even in areas with multiple hits. For example, it took 8 contact shots of 9 mm FMJ, rapidly placed into the same location before this eleven year old Level II Kevlar vest finally allowed a full penetration, as noted in the photo below: