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.