standards and certifications

ANSI Z87.1 is an important norm for the eye pro­tec­tion indus­try in the USA. This stan­dard covers dif­fe­rent types of eyewear: spec­ta­cles, goggles and face shields as well as pre­scrip­ti­on and plano lenses. ANSI Z87.1 gives general descrip­ti­ons and requi­re­ments to the eyewear and pro­vi­des the test methods.
The general requi­re­ments to the eyewear include the optical quality, lumi­nous trans­mit­tance, refrac­ti­ve powers and haze for clear lenses. The general phy­si­cal requi­re­ments are no sharp edges and no other defects that may cause dis­com­fort or injury. The minimum covera­ge area is also checked to make sure that eyewear doesn’t rest­rict the view field of the user. The ”drop ball test” is appli­ca­ble only in case of no high mass impact and velo­ci­ty tests are done. The eyewear has to endure also the igni­ti­on and cor­ro­si­on (if there are any metal parts) tests. Eyewear shall provide a good and tight lateral covera­ge of the eye. The high mass and high velo­ci­ty tests are passed if no part of the eyewear becomes detached from the inner surface, if there is no frac­tu­re, no com­ple­te pene­tra­ti­on of the pro­jec­ti­le through lens or frame, no rupture of the lens.
ANSI Z87.1 lays down also the requi­re­ments to the optical radia­ti­on pro­tec­tion. Among the common indus­tri­al filters like infrared and visible light pro­tec­tion (for welding), the stan­dard lays down the cri­te­ria for pro­tec­tion against ultra­vio­let radia­ti­on. While the first two are not needed in the bal­li­stic glasses, the latter is very important. All Swis­seye tac­ti­cal lenses hence offer a com­ple­te UV pro­tec­tion up to 400 nm.

DIN EN 166 is an Euro­pean norm which defines the per­so­nal eye pro­tec­tion requi­re­ments.
This norm uses the common pro­ce­du­res of EN 167, EN 168 and EN 170.
EN 167 defines the optic requi­re­ments for the pro­tec­ti­ve eyewear: sphe­ri­cal, astig­ma­tic and pris­ma­tic power. The results of the test of the above men­tio­ned refrac­ti­ve powers are clas­si­fied into three cate­go­ries. The optical class 1 is the highest one and allows eyewear to be used per­ma­nent­ly. All Swis­seye lenses fulfill the requi­re­ment of the optical class 1.This test method also checks the light trans­mis­si­on (light fil­te­ring) as well as light dif­fu­si­on and quality of mate­ri­al and surface.
EN 168 deter­mi­nes non-optic tests like the test on increased robust­ness, sta­bi­li­ty at ele­va­ted tem­pe­ra­tures, UV resis­tance and resis­tance to igni­ti­on, high speed impact, resis­tance to fogging and pro­tec­tion against gases, dust, and smoke. Accor­ding to EN 166, glasses may be tested with high speed par­tic­les with low energy impact only (marked as F, energy of about 0,87 J) while goggles may have the medium energy impact (B, ca. 6,19 J) and full-face shields are the only ones allowed the test with high energy impact (A, ca. 15,52 J).
F stays for the safety against high speed par­tic­les with low impact energy and T is for pro­tec­tion against the high speed par­tic­les at high tem­pe­ra­tu­re con­di­ti­ons.
EN 170 tests the pro­tec­tion of the object against ultra­vio­let radia­ti­on. The marking on the lenses like 2C‑1.2 for clear and yellow lenses and 5–3.1 for smoke are defined by the result of this test, where the kind of filter is shown in the part before the hyphen and the shading is the part after the hyphen.  All tac­ti­cal lenses offer the UV pro­tec­tion up to 400 nm.
You will find more details about the marking on the glasses and their expl­ana­ti­ons in the manual “Infor­ma­ti­on for users” enc­lo­sed to the EN 166 tested tac­ti­cal glasses.

MIL-PRF-31013 is an US mili­ta­ry norm that covers the requi­re­ments for a special pro­tec­ti­ve eyewear to provide bal­li­stic eye pro­tec­tion. It descri­bes the general requi­re­ments to the spec­ta­cles like, optical qua­li­ties, UV pro­tec­tion, light trans­mis­si­on levels, che­mi­cal resis­tance and tem­pe­ra­tu­re sta­bi­li­ty, bal­li­stic qua­li­ties of the spec­ta­cle etc.
The bal­li­stic resis­tance is defined by the test method spe­ci­fied in MIL-STD-662. It uses a 0.15 caliber, 5,8 grain to gain the V0 or V50. V50 is the velo­ci­ty at which com­ple­te and incom­ple­te pene­tra­ti­on are equally likely to occur. V0 point is the maximum velo­ci­ty at which no com­ple­te pene­tra­ti­on will occur. Our model Raptor showed e.g. no pene­tra­ti­on at 660 fps in the test report of this norm. The tem­pe­ra­tu­re tests are done at the pro­lon­ged con­di­tio­ning with ‑50 and +70°C where object shall show no dis­tor­ti­on or dis­co­lo­ra­ti­on. Solar radia­ti­on and humi­di­ty shall not affect the glasses. The glasses shall also absorb 90% of the UV radia­ti­on up to 380 nm.

MIL-PRF-32432 is a US mili­ta­ry norm for glasses and goggles for both pre­scrip­ti­on and non-pre­scrip­ti­on wearers. MIL-PRF-32432 lays down that the eyewear kit shall include spare lenses, case, ins­truc­tion booklet, clea­ning cloth and strap depen­ding on the kind of the kit. Goggles must also have a pro­tec­ti­ve sleeve. Spec­ta­cles and goggles have to be com­pa­ti­ble with the pre­scrip­ti­on holder, which Swis­seye calls RX clip adapter.
Lenses have to be easily detached without using any tools. The eyewear has to be light­weight, durable and com­pa­ti­ble with other mili­ta­ry equip­ment like weapons, clot­hing, helmets etc. The textile has to be resistant to mildew. The eyewear shall show no degra­da­ti­on under the expo­sure of extreme tem­pe­ra­tu­re (from ‑50 to +70°C), solar radia­ti­on, humi­di­ty, adhe­si­on, wind and dust. The optical requi­re­ments include lumi­nous trans­mit­tance of the light and the allowed spec­tral trans­mit­tance, chro­ma­ti­ci­ty, a wide field of view and the resis­tance to optical degra­da­ti­on because of fogging and scrat­ching. The lenses shall absorb the UV radia­ti­on from 290 to 380 nm. This norm uses the test methods of ANSI Z87.1 for the fol­lo­wing issues: requi­re­ments for the pris­ma­tic power, high impact pro­tec­tion, flamma­bi­li­ty and cor­ro­si­on resis­tance to salt water as well as tem­pe­ra­tu­re and humi­di­ty requi­re­ments. Bal­li­stic frag­men­ta­ti­on pro­tec­tion after MIL-PRF-32432 is done with a pro­jec­ti­le of 0.15 caliber and 5.85 grain for spec­ta­cles at the velo­ci­ty of 640–660 fps (195–201 ms). For goggles the hit must be done with a 0.22 caliber, 17 grain at 550–560 fps (167–170 ms). The lens shall not be com­ple­te­ly per­fo­ra­ted, shat­te­red, cracked or frac­tu­red. The frame shall stay atta­ched to the lens during this test.
Our goggle G‑Tac has suc­cessful­ly been tested to the pro­tec­tion against the bal­li­stic frag­men­ta­ti­on accor­ding to MIL-PRF-32432 and showed no pene­tra­ti­on of the pro­jec­ti­le at the highest allowed velo­ci­ty.

MIL-DTL-43511D is an US mili­ta­ry norm that covers general and per­for­mance requi­re­ments for curved poly­car­bo­na­te flyer’s helmet visors worn by aircrew per­son­nel. The bal­li­stic test is con­duc­ted using the caliber 0.22, 17 grain accor­ding to T37 FSP (frag­ment simu­la­ting pro­jec­ti­les). The velo­ci­ty of the pro­jec­ti­le is detec­ted by a light beam 34,29 cm (13,5 inches) in front of the test sample. Pene­tra­ti­ons are deter­mi­ned by exami­ning of an alu­mi­num foil mounted behind the visor. Sample gets shot on the right and left side.
The test sample is requi­red to with­stand 167,6–170,7 m/s (550–560 fps) velo­ci­ty. Our model Raptor has suc­cessful­ly com­ple­ted the test with­stan­ding 170,9 m/s (560,6 fps) without any pene­tra­ti­on. This value comes up to 16 J.

STANAG 4296 is one of many NATO stan­dar­diza­ti­on agree­ments con­cer­ning mili­ta­ry pro­ce­du­res and equip­ment. It states the overall cha­rac­te­ristics for the mili­ta­ry pro­tec­ti­ve eyewear like light­weight and com­for­ta­ble fitting, fogging and scratch reduc­tion, not less than 160° clear vision field, com­pa­ti­bi­li­ty with other pro­tec­tion gear and of course impact pro­tec­tion defined by STANAG 2920.
STANAG 2920 test pro­ce­du­re deter­mi­nes the V‑50 bal­li­stic limit for body pro­tec­tion mate­ri­al, inclu­ding eyewear. The V‑50 bal­li­stic limit is cal­cu­la­ted from an average between the highest partial and the lowest com­ple­te pene­tra­ti­on velo­ci­ties on the test object. E.g. figures from STANAG 2920 for the orange lens of 40291 Night­hawk show average partial pene­tra­ti­on of 247 m/s and average com­ple­te pene­tra­ti­on of 258,3 m/s. The V‑50 is the average of both figures and makes 252,7 m/s (829,1 fps). STANAG 2920 test is done with 3,6 mm caliber and 0,325 g bullet mass from 3,8 meters. The sample has a pre­ce­dent con­di­tio­ning at the given tem­pe­ra­tu­re and humi­di­ty. These regu­la­ti­ons provide uniform test con­di­ti­ons equal for all test objects.
STANAG 4296 is an important refe­rence point for the mili­ta­ry envi­ron­ment as well as for sports and hobby shoo­ters and hunters. In addi­ti­on, it is also signi­fi­cant for airsoft, as instead of defi­ning the thres­hold for dif­fe­rent pro­tec­tion levels, it shows exactly how much impact energy and velo­ci­ty each single product with­holds. Each airsoft field has own rules con­cer­ning maximum energy impact allowed, depen­ding on the art of airsoft gun. However most fields don´t go over 3 J. Guns with even lower impact can heavily damage the eye, which makes the per­so­nal pro­tec­tion com­pul­so­ry. Night­hawk e.g. was tested with V‑50 of 10,4 J.

This norm is the Euro­pean Stan­dard that spe­ci­fies the special requi­re­ments (mecha­ni­cal, optical, and so on) for sun­glas­ses and sun­gla­re filters for pro­tec­tion.