The numbers and markings inside your eyewear indicate specific safety ratings.
The numbers and markings inside your eyewear indicate specific safety ratings as set out in the American National Standards Institute (ANSI) safety standard Z87.
Through ANSI Z87, certification for safety eyewear is based on common workplace hazards, such as:
• Chemicals or Liquid Splash
Eye protection that is certified compliant with Z87 is marked Z87. Manufacturers of safety eyewear are required to detail how, and verify that, their products meet these standards.
Here we will focus on these three (3) hazards:
• Liquid Splash
In addition we will discuss the product testing methods that protect against these hazards and the safety markings we get asked about the most.
Z87 Impact Testing
The ANSI standards and markings Z87 and Z87+ indicate that eyewear provides wearers with protection against impact hazards.
For safety eyewear to be certified Z87-compliant, it must pass the ball drop test. This test involves dropping a steel ball (diameter: one inch; weight ±2.4 oz) from a height of 50 inches onto the eyewear. If the eyewear (i.e., lenses and frames) remains intact, it will be certified compliant.
The addition of the plus sign (i.e., +) next to the Z87 marking indicates that the eyewear has been subjected to a much tougher set of tests, specifically the high mass impact test and the high velocity impact test.
The High Mass Test
This test consists of dropping a pointed 500 g weight from a height of ±50 inches onto lenses that are mounted on a head form. To pass this test, no pieces from the frames or the lenses may fracture or become detached.
The High Velocity Test
In this test, a 0.25-inch steel ball is shot at 20 specified impact points with speed and distance adjusted depending on the type of safety wear being tested:
• Safety Glasses – the steel ball is shot at a speed of 102 m/h
• Safety Goggles – the steel ball is shot at a speed of 170 m/h
The pass/fail criteria for the high velocity test is the same as the high mass test with the added criterion that the lenses of the eyewear being tested, when struck, cannot come into contact with eye areas on the head form.
Splash and Dust Protection
Eyewear that meets the ANSI Z87.1 requirement for droplet (splash) and dust protection is marked with a code beginning with the letter D.
• Eye protection that provides protection from droplets and splashes is marked D3
• Eye protection that provides protection against dust is marked D4
• Eye protection that provides protection against fine dust is marked D5
Misconceptions about the Liquid Splash Test
The test for splash resistance is solely a pass/fail liquid splash test. Reactive paper is placed on a head form under the eyewear being tested. Circles are drawn on the paper in place of the wearer's eyes and the eyewear is then sprayed with a liquid. If the paper changes colour inside these circles, the eyewear fails. If not, the eyewear can be certified as providing protection against liquid splash.
Adequate Protection against Splash and Dust
Safety goggles protect eyes against dust, splash, and droplet hazards by forming a protective seal around the wearer's eyes, preventing liquid, chemicals, and dust from entering. Ventilated goggles allow air circulation while providing protection against airborne particles, dust, liquids, and light.
Difference Between Direct and Indirect Ventilation Goggles
In most cases, goggles with direct vent systems cannot prevent liquid from coming into contact with the wearer's eyes and would therefore fail liquid splash tests. Goggles with indirect vent systems, however, will likely pass the liquid splash test since they create sufficient barriers between liquid/splash hazards and the wearer's eyes.
Additional Resources for Choosing Safety Eyewear
To help companies be better informed and prepared, the International Safety Equipment Association (ISEA) has created a useful how-to guide for selecting and using eye and face protection equipment.
Another helpful information source is the OHSA website, which advises readers about eye and face protection based on specific sets of hazards.