Eye protection is required when using which classifications of lasers?

Eye protection is critical when using lasers, particularly those classified as Class 3b and Class 4. Class 3b lasers emit direct or scattered radiation that can cause eye injury upon direct exposure, and they can also pose risks to skin depending on the exposure duration and distance. Class 4 lasers are even more hazardous, possessing sufficient power to cause both immediate eye damage and other potential effects such as fire hazards.

Therefore, wearing appropriate eye protection is essential when working with these classifications to safeguard the eyes from harmful radiation and to ensure the safety of both the operator and any bystanders in the vicinity. Given the potential risks associated with these classes, protective eyewear specifically designed for the wavelength of the laser being used is required to minimize the chance of injury.