Which class of laser can cause eye injury from direct beams and reflections?

The correct answer is Class IV lasers. These lasers are capable of causing eye injury from both direct beams and reflections due to their high output power. Class IV lasers can emit a power level greater than 500 milliwatts, allowing them to pose significant risks with both direct exposure and reflections from surfaces. They can cause severe damage to the retina and even lead to permanent vision loss, making safety precautions critical when using these lasers.

In contrast, Class I lasers are inherently safe and do not emit harmful radiation during normal operation. Class IIA lasers, typically seen as low-power lasers, are considered safe under normal conditions and also do not pose a significant risk of eye injury. Class IIIB lasers can cause eye damage from direct exposure; however, they generally have lower power levels compared to Class IV lasers and pose less risk from reflections. Thus, Class IV lasers are distinctively recognized for their potential for serious eye injuries, underscoring the importance of adherence to safety protocols when operating such devices.