Laser Terminology

The following terminology is often used within the various safety regulation standards:

Maximum Permissible Exposure (MPE) - the highest laser energy to which the eye or skin can be exposed for a given laser without causing hazardous effects or adverse biological changes.

Nominal Hazard Zone (NHZ) - the area within which the level of the direct, reflected, or scattered radiation of a laser during normal operation exceeds the applicable MPE.

Nominal Ocular Hazard Distance (NOHD) - distance along the laser beam axis beyond which eye exposure to the beam is acceptable.

Personal Protective Equipment (PPE) - eyewear such as safety glasses, goggles, or face shields that are manufactured expressly for use in shielding workers' eyes from laser beams. PPE also includes beam shields and clothing that reduces the radiation to levels below the MPE for specific UV wavelengths. Clothing that is made of flame retardant material is recommended for work around Class 4 lasers.

To learn more about Laser Safety Officer visit our Industrial Laser Safety Officer Online Training web page.