Which class of laser has a maximum power of 0.5 W?

The correct classification for lasers with a maximum power of 0.5 W is Class 3b. Class 3b lasers are defined as those that can cause immediate skin injury or eye damage if viewed directly, but they typically have power outputs that can range from 5 mW to 500 mW. Therefore, a laser with a maximum power of 0.5 W falls within this classification, as it exceeds the lower threshold of Class 3a but does not reach the higher output levels that would place it in Class 4.

Understanding the distinctions among the classes is important. For instance, Class 2a includes visible lasers with lower power outputs (up to 1 mW), which do not pose a significant risk under normal circumstances and can be viewed safely for short periods, while Class 3a lasers operate at higher power but still do not necessarily result in immediate eye damage without prolonged exposure. Class 4 lasers, on the other hand, are those that can cause severe injury and have higher power levels, typically above 500 mW. Therefore, the correct identification of Class 3b for a 0.5 W laser is crucial for respecting safety protocols regarding laser use and potential health risks.