Prescription eyeglasses sold in the United States are impact tested. Federal rules have required it since 1972. The test is specific: a 5/8-inch steel ball weighing about half an ounce, dropped onto the lens from a height of 50 inches. The lens must not crack, chip, or break.
That is a genuine test, and it is the reason modern lenses rarely shatter when a pair of glasses hits a tile floor. It is not a workplace test.
Safety eyewear clears a different bar. For a basic impact rating under the ANSI/ISEA Z87.1 standard, the lens takes a one-inch steel ball — more than four times the weight — from that same 50 inches. For a high-impact rating, a quarter-inch steel ball is fired at the lens and frame together at about 102 miles an hour, at 20 separate points on the assembly.
OSHA does not allow ordinary glasses to stand in. Under the agency's eye and face protection rule, an employee who wears prescription lenses around eye hazards has to be given protection that either builds the prescription into the design or fits over the everyday glasses without pushing either pair out of position.
Prescription safety eyewear carries its own marking: Z87-2 on the frame, or Z87-2+ when it is rated for high impact. If the glasses at your workstation do not have it, they are eyeglasses, not protection.
Rick Good spent ten years in the newspaper business, including with The News & Observer (Raleigh, NC) and The Greenville News (Greenville, SC). He co-wrote, with Melinda Coleman, Rutledge to Riley: Governors of South Carolina, 1776–Present (Published by The Greenville News), and is the author of Mind Games Trivia #1 (Amazon). He has recently spent 15 years creating original trivia content through Sounds Good Mobile Entertainment and continues that with his new company, SGME Software. He edits The Smart Reader’s money, real estate, and business coverage.
