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• Laser Safety Control Measures

1. Engineering controls
   1.  protective housing shall be provided
   2.  warning labels shall be conspicuous
   3. interlocks shall be provided on removable parts of the housing
   4. a permanent beam stop or attenuator should be provided
   5. the area should be posted with the appropriate warning sign
   6. if the laser has a service access panel, it shall be interlocked or require a tool for removal
   7. if the MPE is exceeded, a temporary laser controlled area shall be devised
   8. if the MPE is exceeded, viewing portals and/or display screens shall be designed such that MPE is not exceeded
2. Administrative and procedural controls
   1. education and training shall be provided for operators, maintenance and service personnel
   2. alignment procedures shall ensure that the MPE is exceeded
   3. if embedded Class 3b or 4 laser and the MPE is exceeded, service personnel shall comply with the control measures appropriate for the class of the embedded laser

Laser Class 3b

1. Engineering controls
   1. protective housing shall be provided
   2. interlocks shall be provided on removable parts of the housing
   3. if the entire beam in not enclosed, a NHZ determination shall be made by the laser safety officer; a controlled area shall be established and control measures shall be implemented
   4. if there exists a limited open beam path, a NHZ determination shall be made by the laser safety officer
   5. the appropriate warning signs shall be posted
   6. the controlled area shall be operated by trained and authorized personnel
   7. if the NHZ leaves an indoor controlled area, the controlled area shall have a limited beam path
   8. a key-controlled master switch should be provided
   9. a remote interlock connector should be provided
   10. a permanently attached beam stop or attenuator should be provided
   11. an alarm, warning light, or verbal countdown should be used during use or start-up of the laser
   12. if an imbedded Class 4 laser, service access panels shall be interlocked or require a tool for removal
   13. if the MPE is exceeded:
       • viewing portals and/or display screens shall be designed such that the MPE is not exceeded
       • collecting optics shall be designed such that the MPE is not exceeded
   14. the controlled area should:
       • be supervised by an individual with knowledge of laser safety
         have limited access to spectators
       • have beam stops to terminate potentially dangerous laser beams
         be designed to reduce diffuse and specular reflections
       • have eye protection for personnel
       • not hbeam at eye level with people
       • have restrictions on windows and doorways to reduce exposure to levels below the MPE
       • require storage or disabling of the laser when it is not being used
   15. if used outdoors, a Class 3b laser shall:
       • have an established NHZ
       • have restrictions on unauthorized persons in areas where the MPE is exceeded
       • have appropriate controls if personnel are within the NHZ
       • be designed such that a beam path is not near eye level of a sitting or standing person
       • be terminated with a beam stop when possible
       • be disabled when not in used
       • only be operated by qualified and authorized personnel
       • bear appropriate warning labels in a conspicuous place
       • have appropriate warning signs posted in the area
2. Administrative and procedural controls
   1. education and training shall be provided for laser operators, maintenance and service personnel
   2. only authorized personnel shall service the laser
   3. alignment procedures shall ensure that the MPE to the eye is not exceeded
   4. control procedures shall be followed by service personnel
   5. the laser safety officer shall implement controls necessary to reduce exposure if the laser safety officer considers exposures to be excessive
   6. approved, written standard operaing, maintenance,, and service procedures should be developed
   7. appropriate eye protection should be required
   8. unauthorized persons should not be permitted within the controlled area

Laser Class 4

1. 1. Engineering controls
   1. protective housing shall be provided
   2. interlocks shall be provided on removable parts of the housing
   3. service access panels shall be interlocked or require a tool for removal
   4. a key-controlled master switch shall be provided
   5. when the entire beam in not enclosed, a NHZ shall be established
   6. when there exists a partially limited beam path, a NHZ shall be established
   7. a permanent beam stop or attenuator shall be provided
   8. an alarm, warning light, or verbal countdown shall be used during use or start-up of the laser
   9. the controlled area shall:
      1. be restricted to authorized personnel only
      2. be designed to allow for rapid emergency egress
      3. be equipped with a device that allows for deactivation of the laser or reduction of output to below the MPE
      4. be designed to fulfill Class 3b controlled area requirements
      5. be designed with entry safety controls
   10. the laser should be monitored and fired from a remote location
   11. if used outdoors, a Class 4 laser shall:
       1. have an established NHZ
       2. be restricted from the presence of unauthorized personnel if the MPE is exceeded
       3. have appropriate controls if personnel are permitted in the NHZ
       4. have a beam path that is not at eye level with sitting or standing persons
       5. be terminated by a beam stop, if possible
       6. be disabled when not in use
       7. be operated only by authorized personnel
       8. be evaluated for necessary personnel protective equipment in inclement conditions
       9. have warning labels in a conspicuous place
       10. have a warning system which activates prior to emergence of the beam
   12. if the MPE is exceeded:
       1. viewing portals and/or display screens shall be designed so as not to exceed the MPE
       2. collecting optics shall be designed so as not to exceed the MPE
2. Administrative and procedural controls
   1. approved, written standard operating, maintenance, and service procedures shall be required
   2. education and training shall be provided for operators, maintenance, and service personnel
   3. only authorized personnel shall operate, maintain or service the laser
   4. alignment procedures shall ensure that the MPE for the eye is not exceeded
   5. eye protection shall be required
   6. spectators shall be prevented from the controlled area
   7. service personnel shall comply with control procedures
   8. the laser safety officer shall take measures to reduce output if the output is considered to be excessive

* For specific information on laser control measures, refer to ANSI Z136.11

Additional resource: General laser safety information in the NMSU Lab Safety Guide