How does ANSI Z87.1-2003 and Mil-PRF-31013 apply to AS?

I am posting this here so others may review my findings before I publish it in a wider venue. Any comments and or corrections would be very much appreciated.

Thank you,

Mikhail.

Question: How does ANSI Z87.1-2003 and Mil-PRF-31013 apply to Airsoft eye wear?

What do these standards mean for our sport? Here I will test each standards specs to see if they aid in finding good safety gear for Airsoft.

Specifications:
ANSI Z87.1-2003 high velocity -

150 fps of a 0.25 inch diameter steel ball (25 caliber) at point of impact

Mil-PRF-31013 Vo ballistic test
640-660 feet/second of a 0.15 inch diameter steel projectile (15 caliber)

Question: what is the Joule rating for ANSI Z87.1-2003 high velocity ?

Find a .25" Diameter steel ball weight
http://www.precisionballs.com/ball_weight_and_density.html

Volume of a Sphere is (4 * pi * R * R * R)/ 3

Density of steel is 0.283

Weight = Volume * Density
Weight = (4 * pi * R * R * R)/ 3 * Density
Weight = (4 * 3.1416 * 0.125 * 0.125 * 0.125)/ 3 * 0.283
Weight = 0.00231529375 pounds
Weight = 1.05019958 grams or roughly 1.0g

Energy rating of ANSI standard = 1.04 Joules

Now for Milspec

Find weight of 0.15 inch diameter steel projectile

Weight = (4 * 3.1416 * 0.075 * 0.075 * 0.075)/ 3 * 0.283
= 0.00050010345 pounds
= 0.226843109 grams

Energy Rate of 460 FPS with a .226g projectile is 2.21 Joules

Discussion:
Of the two the Milspec is closer to our sport as the projectile is the same as our average bb mass. Also the Velocity is closer to our normal FPS. It results in a 2.21 Joule rating that is OVER our usual Field guidelines. Higher would be better, but this is still better than nothing as far as existing standards go.

The ANSI Z87.1-2003 (high velocity) standard uses a slower velocity and larger projectile than we use...and a resulting lower Impact rating than what we need to protect our eyes. The 1.04 Joule rating is lower than many of our field limits and therfore unsafe to use as AS safety standard.

Conclusion:

Using ANSI Z87.1-2003 (high velocity) standard as a safety standard for airsoft would be allowing eyewear insufficent to protect against the average AS rifle.

Mil-PRF-31013 (Vo ballistic test) is a SLIGHTLY BETTER standard as it fits our projectile physics BUT is lower than most accepted safety standard, which is usually a mulitple of the average usage...not just slightly ABOVE average usage.

Ah HA! just found a math error.

Milspec rating specs 650 fps not 460...this give the milspec a 4.4Joule rating....muuuuch better. That standard now gives some margin of safety for AS use.

Still not impressed with the ANSI Z87.1 standard though.

Ok, I will amend the discussion and conclusion. (what is it about posting something that reveals its errors?... )

Discussion:
Of the two the Milspec is closer to our sport as the projectile is the same as our average BB mass. Also the Velocity is closer to our normal FPS. It results in a 4.41 Joule rating that is OVER our usual Field guidelines by a factor of 2. This is a minimum amount for safety...engineers may argue a still higher multiple than just a factor of 2.

The ANSI Z87.1-2003 (high velocity) standard uses a slower velocity and larger projectile than we use...and a resulting lower Impact rating than what we need to protect our eyes. The 1.04 Joule rating is lower than many of our field limits and therefore unsuitable to use as AS safety standard.

Conclusion:

Using ANSI Z87.1-2003 (high velocity) standard as a safety standard for airsoft would be allowing eye wear insufficient to protect against the average AS rifle.

Mil-PRF-31013 (Vo ballistic test) is a BETTER standard as it fits our projectile physics and allows a safety margin of a factor of 2. so could be considered a minimum for safe airsoft use.

Another standard is the Airforce standard MIL-DTL-43511C/D which covers general and performance requirements for curved polycarbonate flyer’s helmet visors worn by aircrew personnel.

3.5.10 Ballistic resistance. The ballistic resistance of the lenses shall be such that they will pass a V0 test using a 0.22 caliber... projectile at a velocity of 550 to 560 feet per second ...

Weight of 0.22 inch diameter steel projectile

Weight = (4 * 3.1416 * 0.11 * 0.11 * 0.11)/ 3 * 0.283
= 0.0015778078624 pounds
= 0.715681608 grams

Energy Rate of 555 FPS with a .716g projectile is 10.19 Joules

Both these milspec are used in certain masks. Of the JT line I find milspec use in only 2 of their products, both Revision...one Dessert Locust, and SawFly.

i quote the specs here (shown under the replacement lenses details):

"High-impact protection certified to ANSI Z87.1 and Military Requirements (MIL-V-43511C clause
3.5.10 and MIL-PRF-31013 clause 3.5.1.1). Polycarbonate lenses offer 100% protection from UV-A, UV-B
and UV-C rays."

I mention these masks only to show that these specs DO have meaning in Airsoft...and know we can even begin to measure what that may be.

oh...and that I don't trust your average paintball mask...Z87.1.....ya, right.

My first clue was when ANSI Z87.1 was asked for by field insurance agencies

headbang....headbang.

Sigh...three problems.

1)Z87.1 high impact specifications use different FPS for spectacle/glasses versus goggles. 150fps for glasses...250 for goggles.

Energy rating of ANSI standard goggle rating with 1.0g projectile @250fps = 2.89 Joules. Good news right? just wait...

2) This rating is for one hit only. After that its not rated by ANSI for further hits. When they came up with this standard originally it was intended for safety gear. One hit, you replace that safety gear. Sooooo if you have used your mask for AS previously and show any scuffs from hits...it is no longer ANSI certified. Well...it IS but just not as safety equipment. sigh. They will in no way indicate that the mask or goggle will withstand a second hit by this standard.

3) Basic Impact spectacle lenses will have the manufacturer’s mark, i.e. an AOSafety product will have “AOS” and a Pyramex product will have a "P" etc. Goggles and face shields will have AOS and Z87 (AOS Z87) If this is ALL that is on your goggle/mask than it has no fps rating via ANSI....its just basic. It is rated to stop a 1" ball dropped from 50"...yippee. (once)

The old standard had a thickness requirement...so the old standard would quite often surpass the standard by a good margin due to the thickness ( 3mm) required for certification. The newer standard has dropped that, so lenses are now make thinner for just enough to qualify for this standard...thus less robustness, less margin of safety. How can you tell if you have old or new non-high velocity stuff? There is no marking difference between new and old unless the new is High Impact and marked accordingly.

High Impact spectacle lenses will have a plus + sign, (AOS+) or "P+" etc. All goggle lenses and face shield windows are to be marked with the manufacturer's mark, Z87, and a + sign (AOSZ87+)

THESE and these alone (Manufacturer Mark and Z87 and +) have the 2.89 Joule rating....for one hit.

I now hate this standard. What a lovely attribute for marketing, with almost no commitment to anything.

Grrrrrrrr.

It's a good thing we aren't shooting each other with 1g Steel Balls at 250 FPS

But, yeah after getting a good size dint on my mesh mask i've been looking for a new set. One with a fan, or one i can easily mod a fan into. Paint chips and BB fragments are starting to worry me.

https://www.sealsactiongear.com/catalog/store/comersus_viewItem.asp?idProduct=409 Is my first thought. The one with the Turbofan is outrageously priced at $195 A pair of 20mm PC fans are like 10 with a 9v battery clip.

Hmmm.. MIL-V-43511C certified...thats more like it. So that lens should now take a 10 Joule hit. If I was dropping serious money I would be tempted to contact the manufacter and ask if the whole mask is certified 43511.

Just a thought.