FOCUS ON LASERS Campbell Basic Laser...• ANSI Z136.1 –2014 American National Standard for the...
Transcript of FOCUS ON LASERS Campbell Basic Laser...• ANSI Z136.1 –2014 American National Standard for the...
FOCUS ON LASERS
Philip Campbell
RADIATION SAFETY: Principles, Practice, and Emerging Issues
March 2018
This is a very basic training on laser safety. This training will not provide enough information to be an Laser Safety Officer.
DISCLAIMER
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• Laser Basics
• Hazards– Biological Effects
– Non-beam Hazards
• Laser Classifications
• Control Measures
TOPICS
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LASER BASICS
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LASER BASICS
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LASER BASICS
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• Continuous Wave (CW) - ≥ 0.25 seconds
• Pulsed - <0.25 seconds– Q-switch – produces very short intense laser pulses (~10 to 250 ns)
LASER BASICS
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BIOLOGICAL EFFECTS
The wavelength will determine which part(s) of eye are damaged
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Nd:YAGCO2
UV-B/C UV-A Visible IR-A IR-B IR-C
Photo-keratitis, cataract
Erythema (sunburn)Accelerated skin ageing
Pigmentation
Retinal damage Corneal burns
Cataracts
Skin burn
Photochemical effect Retinal Damage Not “Eye Safe” Heating Surface of the Eye (thermal effects)
reflected off a
mirror. Permanent
vision damage
BIOLOGICAL EFFECTS
Burn similar to thermal and solar burns
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REFLECTION HAZARDS
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NON-BEAM HAZARDS
• Electrical
• Non-Laser Radiation
• Fire
• Chemicals/air contaminants
• Human Factors
LASER CLASSIFICATION
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Nd:YAG Laser Marker
• All wavelengths
• Incapable of causing injury during normal operation
• Low power or enclosed beam– May be higher class during
maintenance or service
Class 1M – may be hazardous when viewed with collecting
optics
LASER CLASSIFICATION
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• Visible lasers only– Staring into beam is eye hazard
• Eye protected by aversion response (blink reflex)
Class 2M – may be hazardous when viewed with collecting optics
CLASS II LASER PRODUCT
Laser RadiationDo Not Stare Into Beam
Helium Neon Laser1 milliwatt max/cw
Laser Scanners
LASER CLASSIFICATION
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• All wavelengths
• Potentially hazardous under some direct and specular viewing conditions– Probability of actual injury is small
• Aversion response may not provide adequate protection
• Reduced control requirements
Laser Pointers
Small Beam
(Class 3R)
LASER CLASSIFICATION
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• All wavelengths
• May be hazardous under direct or specular viewing conditions
• Normally not a hazard for– Fire
– Diffuse reflection
– Laser generated air contaminant (LGAC)
LASER CLASSIFICATION
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• All wavelengths
• Hazard to eye or skin from direct beam
• May be a hazard for– Fire
– Diffuse reflection
– Laser generated air contaminant (LGAC)
– Plasma radiation
CONTROL MEASURES
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HIERARCHY OF CONTROLS
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CONTROL MEASURES
• Emergency Shutoff
• Interlock
• Key
• Protective housing
• Labels
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CONTROL MEASURES
• Nominal Hazard Zone – Area in which the direct, reflected or scattered radiation may exceed permissible exposure levels without PPE
• Access Control
• Barriers
• Warning devices and signs
• Safety Interlocks
• Location of controls
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CONTROL MEASURES
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CONTROL MEASURES
• Visible and/or audible
• Inside and outside controlled area
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CONTROL MEASURES
• Enclosed Beam Path/Protective Housing
• Beam Attenuators/blocks/traps
• Additional Safety Interlocks
• Barriers/Curtains
• Window Protection
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CONTROL MEASURES
• Documented Safety Program with defined responsibilities
• Standard Operating Procedures (SOPs)
• Alignment procedures
• Output emission limits
• Education and Training
• Authorized personnel
• Key Control
• Service Personnel
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LASER SAFETY TRAINING
• Fundamentals of laser operation
• Biological effects of laser radiation on the eye and skin
• Significance of specular and diffuse reflections
• Non-beam hazards of lasers
• Laser and laser system classifications
• Control measures
• Overall responsibility of management and employee
Consider awareness training for other laser classes
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CONTROL MEASURES
• Optical Density (OD) – measure of the transmittance of the wavelength of interest
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• ANSI Z136.1 – 2014 American National Standard for the Safe Use of Lasers
• ANSI Z136.3 – 2011 American National Standard for the Safe Use of Lasers in Health Care
• ANSI Z136.5 – 2009 American National Standard for the Safe Use of Lasers in Educational Institutions
REFERENCES
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• ANSI Z136.6 – 2005 American National Standard for the Safe Use of Lasers Outdoors
• ANSI Z136.8 – 2012 American National Standard for the Safe Use of Lasers in Research, Development, or Testing
• ANSI Z136.9 – 2013 American National Standard for the Safe Use of Lasers in Manufacturing Environments
REFERENCES
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