Low power devices that either have insufficient power to cause damage or their enclosures prevent emission of damaging levels of radiation. For example CD players. Class IIIa laser product - output can cause biological damage to the retina if beam is view for seconds or if the beam is focused. With visible laser light of this intensity natural avoidance reaction usually protects vision from serious damage. Class IIIb laser product - can cause biological damage to the eyes if viewed briefly.
Intensity is sufficiently powerful to cause damage with brief exposure.
Natural avoidance reaction will not protect from retinal damage. Class IV laser product - direct viewing and specular as well as diffuse reflections can cause biological damage to the eyes or skin. These laser present a thermal hazard. All rights reserved.