What does Z87 stand for?
Browsing through a safety glasses selection, you’re likely to see Z87 on some of the glasses. What does Z87 stand for? Is it simply the piece number to identify a glasses piece when you call customer support? Or does it mean something else?
When assessing whether safety glasses meet a certain standard which ensures that they will effectively and without a doubt prevent injuries resulting from safety hazards, there are many different standards, in many different countries. In the United States, the minimum standard required for occupational and industrial uses is the ANSI Z87.1-2010. This standard has been around for approximately forty years, and its latest revision was in 2010.
This minimum standard takes into account many potential hazards, and requires all certified glasses to be able to withstand all of them. Such hazards include impacts, radiation, chemicals, and hazards resulting from welding. The ANSI Z87.1-2010 also includes a Z87+, which means that unlike a standard Z87 certified pair of glasses, which is only certified to withstand basic impacts, a Z87+ can withstand high impacts. Nowadays, however, a standard Z87 certified pair of glasses is rated “non-impact” while a Z87+ pair is “impact rated.”
The ANSI Z87.1-2010 is also designed to give consumers an idea about which hazards a particular pair of glasses has been tested to withstand, by having a basic and simple system in place to rate each individual pair of glasses.
Here are some of the designations in the ANSI Z87.1-2010 system:
- D3: Splash and droplet.
- D4: Dust.
- D5: Fine dust.
- W: Welding (also mentions shade number).
- U: UV (also mentions scale number).
- R: Infrared light (also mentions scale number).
- L: Visible light filter (also mentions scale number).
- Z87-2 : Prescription.
- H: Products designed for smaller heads.
- V: Photocromic.
- S: Special lens tint.
- Z87+: Impact rated, meaning it was tested to withstand high-velocity impacts.
All these markings must be displayed permanently, on the front of the glasses frame and on the temples.
How Z87+ Certified Glasses Are Tested
In order for a pair of glasses to be Z87+ certified, they must go through the following two tests.
- High mass impact. To make sure that the glasses will survive and shield its wearer in the case of a heavy impact from a heavy, pointed tool, the following test is done. A pointed projectile, weighing 500 g, or 17.6 oz, is dropped on the glasses from a height of 50 inches. The glasses must not only stay intact, without any part of it breaking off, but the lens must also not be fractured.
- High velocity impact. To simulate particles, such as chips, which may be ejected from machines or during grinding processes, a 1/4 inch steel ball is dropped on the glasses at six different points of the glasses. Again, the glasses must remain entirely intact, and the lens must not fracture. Following is the speed at which the ball is dropped: For spectacles, the speed is 150 fps (feet per second); For goggles, 250 fps; For face shields, 300 fps.
Other Tests And Requirements
- No more than 3% haze may occur on the lenses.
- No more than 1.5 mm openings on the side.
- Lens must function properly even after being cleaned.
- For the other markings mentioned above, such as UV, D3, D4, etc, other tests are conducted.
- Many other tests and requirements exist, which are beyond the scope of this article.
Although the latest Z87 version is from 2010, OSHA may also accept the previous two versions, namely from 2003 and 1989, as well as other certifications, if the manufacturer can prove that they meet the Z87 standards. Certification is not done by an independent, outside inspector; it is done by the manufacturers themselves.
For more information, or if you’re considering purchasing Z87 glasses, feel free to contact us.