What power level indicates a Class 3a laser?

A Class 3a laser is defined as a laser that operates at a power output of less than or equal to 5 mW. This classification includes lasers that pose a low risk of causing eye injury when viewed briefly, as the potential for harm is minimal under normal operation conditions. Lasers in this class are common in applications such as laser pointers and some laser diode applications.

Choosing a power output category of less than 5 mW aligns accurately with the definition of Class 3a lasers. This is essential in industrial hygiene and safety evaluations, as understanding the power levels of different laser classifications helps in assessing hazards and implementing safety measures.

The other options incorrectly categorize the power levels associated with Class 3a lasers. For instance, less than 0.5 mW refers to Class 1 lasers, while power levels between 0.5 W and 1 W are significantly higher and fall into either Class 3b or Class 4 categories, which can pose serious risks to eye safety. Therefore, recognizing that Class 3a lasers are less than 5 mW is crucial for proper identification and adherence to safety protocols.