Laser Safety Manual

Laser Safety Manual 41 is required to be interlocked. Infrared (IR) Radiation Electromagnetic radiation with wavelengths that lie within a range of 0.7 µm to 1 mm. Intrabeam Viewing The viewing condition whereby the eye is exposed to all or part of a laser beam. Irradiance (E) Radiant power incident per unit area upon a surface, expressed in W/cm². Laser A device that produces radiant energy predominantly by stimulated emission. Laser radiation may be highly coherent temporally or spatially or both. Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. Laser Classification An indication of the beam hazard level of a laser or laser system during normal operation or the determination thereof. The hazard level of a laser or laser system is represented by a number or a numbered capital letter. The laser classifications are Class 1, Class 1M, Class 2, Class 2M, Class 3R, Class 3B and Class 4. In general, the potential beam hazard level increases in the same order. Laser Operator An individual who has met all applicable laser safety training, medical surveillance, and approval requirements for operating a laser or laser system. Laser Safety Officer (LSO) The individual who has authority to monitor and enforce the safe use of lasers and laser systems. Laser Supervisor The responsible PI for a laser or laser system. See also Principal Investigator . Maximum Permissible Exposure (MPE) The level of laser radiation to which an unprotected person may be exposed without hazardous effect or adverse biological changes in the eye or skin. MPE is expressed in terms of either radiant exposure (J/cm²) or irradiance (W/cm²). The criteria for MPE are detailed in Section 8 of ANSI Z136.1. Nominal Hazard Zone (NHZ) A zone that describes the space within which the level of the direct, reflected or scattered radiation during normal operation exceeds the applicable MPE. Exposure levels beyond the boundary of the NHZ are below the appropriate MPE level. Optical Density (D λ ) - Logarithm to the base ten of the reciprocal of the transmittance: D λ = -log10 τ λ , where τ λ is the transmittance at the wavelength of interest. Power The rate at which energy is emitted, transferred, or received in W or J/s. Principal Investigator (PI) The authorized laser user who assumes responsibility for the control and safe use of a laser or laser system. The PI is appointed by the Department Chairperson. See also Laser Supervisor .