What is a characteristic of Class 2 lasers related to exposure time?

Class 2 lasers are classified as low-power lasers that emit visible light, typically at wavelengths ranging from 400 to 700 nanometers. The defining characteristic of Class 2 lasers is that they are generally considered safe for short exposure times. Specifically, they are assumed to be safe for exposures of up to 0.25 seconds because the human eye's blink reflex can typically protect against potentially harmful exposure within this brief timeframe.

If exposure extends beyond 0.25 seconds, there is an increased risk of eye damage since the eye may not reflexively blink in time to protect against the light. Therefore, this characteristic emphasizes the importance of limiting exposure duration to ensure safety, reinforcing the premise that brief exposure to Class 2 lasers is unlikely to cause harm.