Testing of Frames for Safety Eyeglasses and Goggles
Frames for safety glasses are tested using the same criteria whether they will be used in basic impact or high impact applications. Frame tests include:
- High mass impact. In this test, a one-inch diameter steel projectile weighing 17.6 ounces is dropped through a tube from a height of 50 inches onto a safety lens mounted in a frame. The frame is "worn" by an artificial head form. To pass, the frame must fully retain the lens, and no piece can become detached from the inner surface of the frame component that holds the lenses.
- High velocity impact. This test involves shooting a quarter-inch steel ball at the lens and frame at a velocity of 150 feet per second from a distance of just under 10 inches. The test is repeated multiple times (each time with a new frame and lens) at different angles and positions of impact. The pass criteria are the same as for the high mass impact test.
- Durability. Safety frames must also pass a flammability-resistance test, a corrosion-resistance test and other durability tests.
How To Assess Standards for Frames Used in Protective Eyewear
Non-prescription safety eyewear with non-removable lenses must be permanently marked with the manufacturer's trademark and "Z87" (basic impact) or "Z87+" (high impact) on either the front of the frame or on one temple.
Prescription safety frames must be permanently marked with the manufacturer's trademark and "Z87-2" on the front of the frame and on both temples.
For complete information, you can purchase a copy of the ANSI Z87.1-2003 safety eyewear standard at the American National Standards Institute website.
What Type of Safety Lenses Do I Need at Work?
Your company's safety officer should determine which level of protection (basic impact or high impact) is needed for your job duties. A few occupations requiring high impact protection in eyewear include:
- Carpenters
- Machinists
- Millwrights
- Plumbers and pipe fitters
- Laborers
Some activities may require side shields, goggles or full face protection. Employers and safety officers should consult OSHA to help determine which type of safety eyewear is most appropriate for different job positions. To learn more, visit the eye and face protection section of OSHA's website.
Also, the International Safety Equipment Association has published the "Eye and Face Protection Use and Selection Guide" as a companion to the ANSI Z87.1-2003 standard. You can purchase this guide from the organization's website.
If you work as an independent contractor, it's best to choose safety eyewear that has been rated at the high impact standard for all activities, just to be extra safe.
What Type of Safety Glasses Are Best for Home Use?
As with independent contractors, you should choose safety frames and lenses rated for high impact, for maximum protection.
If you don't require prescription lenses, or you wear contact lenses, you can purchase non-prescription safety eyewear from most hardware, building supply and sporting goods stores.
These safety glasses usually are made of lightweight polycarbonate for comfort and are available in attractive wrap-style frames. For the greatest protection value, choose models that have the high impact rating. (Look for the "Z87+" marking on the frame.)
Some models are even available with a bifocal reading segment in the bottom half of the lens if you are over age 40 and have presbyopia.
If you need prescription safety glasses, you must purchase these from an eye doctor or at an optical store. Again, for the best protection, choose safety eyewear with a high impact rating. (The lenses will bear the manufacturer's trademark and a "+." The frame will be marked "Z87-2" on the inside of the front and temples.)
For mowing lawns and using a power trimmer or other power tools, choose a frame with side shields to protect you from flying particles or larger objects.
 For sports, use comfortable, padded protective eyewear like this, from RecSpecs. [Click on photo for closeup view.]
What Type of Safety Glasses Are Best for Sports?
The same recommendations for safety glasses for home use apply here. Also, consider purchasing an elastic band that attaches to the back of your temples, to keep your safety glasses securely on your head during active sports.
For hunting and sport shooting, always choose safety lenses that have a high impact rating. Consider a wrap-style frame with a non-shiny, matte finish and lenses with anti-reflective coating, to eliminate distracting reflections.
Safety frames with camouflage patterns are also available for hunting. If you need prescription safety glasses, make sure they have side shields for added eye protection.
For hunting, golfing and other sports that require acute vision, consider adding a sport-specific tint. Amber or yellow tints, for example, can enhance contrast for shooting.
Fish hooks are a major cause of sports-related eye injuries, so for fishing choose a wrap-style frame and safety lenses with a polarized tint, to cut glare from the surface of the water. Eliminating the glare will not only let you see into the water more easily, but it will also make your eyes feel more comfortable.
Also, consider photochromic lenses for optimum vision and comfort in changing outdoor lighting conditions. An optician or other eyecare professional can advise you as to which tints are best for your particular activities.
If you enjoy paintball, be aware that players without proper eye and head protection can sustain devastating injuries from paintball pellets fired from paintball guns. Head shields for paintball should combine eye and ear protection, and the shield should have a high impact safety rating. This is because some guns are capable of propelling paint pellets at speeds over 180 mph.
The most important rule for paintball is, never take your head shield off while you're in the playing area, even when a game has not yet begun.
Which Lens Material Is the Best for Safety Glasses?
The most popular lens material for safety eyewear is polycarbonate. This material has less than half the weight of glass, so the eyewear is more comfortable. Polycarbonate lenses are also more impact-resistant than glass lenses.
Keep in mind that polycarbonate is a much softer lens material than glass. Even with a scratch-resistant coating, polycarbonate lenses will scratch more easily than glass lenses.
Can I Get Anti-Reflective Coating on Safety Glasses?
Anti-reflective coating (or AR coating) reduces distracting lens reflections and therefore may be desirable for certain activities that require safety eyewear. But be aware that AR coating may affect the impact resistance of certain lenses, so impact resistance tests must occur after the coating is applied. Your eyecare professional may need to verify that the optical lab did indeed test the lenses properly for impact resistance after applying the coating.
Your eyesight is precious. Regardless of whether you need non-prescription safety eyewear or prescription safety glasses, the investment you make to protect your eyes and vision will pay dividends as you reduce your risk of a sight-threatening injury.
[Page updated May 2008]
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