ABO NOCE Practice Test

How is impact resistance calculated for safety lenses?

1. 1 inch steel ball dropped from 30 inches

2. 1 inch steel ball dropped from 50 inches

3. 5/8 inch steel ball dropped from 50 inches

4. 3/4 inch steel ball dropped from 40 inches

The correct answer is: 1 inch steel ball dropped from 50 inches

The correct answer is based on the standard set for impact resistance testing of safety lenses. For safety lenses, the impact resistance is determined by dropping a specific size steel ball from a certain height. In this case, the standard specifies testing with a 1-inch steel ball dropped from a height of 50 inches. This method helps ensure that the lenses can withstand impacts that may occur in various environments, effectively protecting the wearer's eyes from potential hazards. The rationale behind using a 1-inch steel ball and the height of 50 inches is based on industry standards, which aim to simulate real-world conditions and extremes that eyewear might face in vocational or hazardous situations. By adhering to these testing criteria, manufacturers can specify their lenses' capabilities and ensure compliance with safety regulations. This testing method provides a reliable assessment of the lens durability, which is crucial for applications where eye safety is a concern.