PO Box 245101 Tucson, AZ 85724-5101 Voice: (520) 626-6850 FAX: (520) 626-2583 rlss.arizona.edu University of Arizona Laser Radiation Protection Reference Guide Research Laboratory & Safety Services Revised January 8, 2018 Research Laboratory & Safety Services (RLSS) is the primary coordinating unit responsible for the radiation safety program at the University of Arizona. The Laser Radiation Protection Reference Guide is maintained at RLSS at 1717 E Speedway Blvd, Suite 1201, Tucson, AZ, and is readily available to anyone via the RLSS website (rlss.arizona.edu). TABLE OF CONTENTS I. INTRODUCTION ................................................................................................ 1 II. PHYSICS ........................................................................................................... 1 A. ATOMIC STRUCTURE ...................................................................................................... 1 B. IONIZING AND NON-IONIZING RADIATION ..................................................................... 1 1. Electromagnetic Spectrum and Lasers .................................................................... 2 C. LASER FUNDAMENTALS ................................................................................................. 2 D. LASER CONSTRUCTION .................................................................................................. 2 1. Laser Mediums........................................................................................................ 3 E. LASER CLASSIFICATIONS ............................................................................................... 4 1. Class 1 ..................................................................................................................... 4 2. Class 2 ..................................................................................................................... 4 3. Class 3a ................................................................................................................... 4 4. Class 3b ................................................................................................................... 4 5. Class 4 ..................................................................................................................... 5 6. Class 1 Laser Products ............................................................................................ 5 III. BIOLOGICAL EFFECTS AND OTHER HAZARDS ............................................... 5 A. LASER INDUCED EYE EFFECTS ....................................................................................... 5 1. Viewing Conditions ................................................................................................ 6 2. Physiology of the Eye ............................................................................................. 7 B. LASER INDUCED SKIN EFFECTS...................................................................................... 8 C. NON-BEAM HAZARDS .................................................................................................... 9 1. Electrical Hazards ................................................................................................... 9 2. Fire Hazards ............................................................................................................ 9 3. Laser Generated Air Contaminants (LGAC) .......................................................... 9 4. Chemical Hazards ................................................................................................... 9 5. Noise ....................................................................................................................... 9 D. PROTECTION AGAINST RADIATION EXPOSURE .............................................................. 9 1. Nominal Hazard Zone (NHZ) and Laser Controlled Area (LCA) .......................... 9 2. Alignment Safety Measures .................................................................................. 10 3. Additional Requirements for Class 4 Laser Laboratories ..................................... 11 E. HAZARD EVALUATION TO IDENTIFY EXPOSURE RISK .................................................. 12 F. PERSONAL PROTECTIVE EQUIPMENT ........................................................................... 12 1. Eye Protection ....................................................................................................... 12 2. Skin Protection ...................................................................................................... 13 IV. LABORATORY PRACTICES ............................................................................. 13 A. EDUCATION AND TRAINING ......................................................................................... 13 B. APPROVAL TO USE LASERS .......................................................................................... 14 C. POSTING AND LABELING FOR LASERS .......................................................................... 14 1. Room and Laser Controlled Area Entrances ........................................................ 14 2. Laser Labels .......................................................................................................... 14 3. Labeling of Enclosures ......................................................................................... 15 D. ACTIVATION, RECORDKEEPING AND SECURITY OF LASERS ......................................... 16 1. Activation .............................................................................................................. 16 2. Recordkeeping ...................................................................................................... 16 3. Security ................................................................................................................. 16 V. EMERGENCY PROCEDURES ........................................................................... 16 A. COMMON CAUSES OF ACCIDENTAL EXPOSURES .......................................................... 16 B. ACTIONS AND NOTIFICATIONS ..................................................................................... 16 C. FIRE EMERGENCIES INVOLVING LASERS ...................................................................... 17 D. LOSS OR THEFT OF LASERS .......................................................................................... 18 VI. RESPONSIBILITIES BY ROLE ......................................................................... 18 A. APPROVAL HOLDER RESPONSIBILITIES ........................................................................ 18 B. RADIATION SAFETY COORDINATOR RESPONSIBILITIES ................................................ 18 C. RADIATION WORKER RESPONSIBILITIES ...................................................................... 18 D. RESEARCH LABORATORY & SAFETY SERVICES (RLSS) RESPONSIBILITIES ................. 19 VII. OBTAINING A LASER ..................................................................................... 19 Tables and Figures Figure 1: Atomic Structure ............................................................................................................ 1 Figure 2: The Electromagnetic Spectrum ...................................................................................... 2 Figure 3: Laser Construction ......................................................................................................... 3 Figure 4: Intrabeam Viewing ......................................................................................................... 6 Figure 5: Specular Refraction ......................................................................................................... 6 Figure 6: Diffuse or Scattered Reflection ...................................................................................... 6 Figure 7: The Human Eye .............................................................................................................. 7 Figure 8: Effect of Visible and Near-Infrared Light ...................................................................... 7 Figure 9: Effect of Mid/Far Infrared and Far-Ultraviolet Light .................................................... 8 Figure 10: Effect of Near-Ultraviolet Light ................................................................................... 8 Figure 11: Sources of Radiation Exposure in the United States ... Error! Bookmark not defined. Figure 12: Eyewear Optical Density and Wavelength Markings ................................................ 13 Figure 14: Sample Laser labels .................................................................................................... 15 Figure 13: Sample Entrance Warning Signs ................................................................................ 14 I. Introduction The Laser Protection Reference Guide serves to describe the Laser Safety program at The University of Arizona (UA) and to provide information regarding the safe use of lasers. The Laser Safety program primarily addresses hazard Class 3b and 4 lasers and products containing lasers in these classes. The responsibilities Research Laboratory & Safety Services (RLSS), Laser Safety Officer (LSO), Approval Holders, Radiation Safety Coordinators and Radiation Workers are also described. The program is intended to: Provide a basic introduction to ionizing and non-ionizing radiation, lasers, and the hazards associated with laser use; Provide guidance to Approval Holders and workers authorized under their