Certified Laser Safety OfficerExam Reference Guide

Board of Laser Safety Certified Laser Safety Officer ProgramExamination Reference GuideTable of ContentsGeneral Information .1Examination Information .2Other Hard Copy Materials .3Web Pages and Free Online Tutorials .3Laser Safety Equation Sheets.5Selected Maximum Permissible Exposures (MPEs) .5Correction Factors from Table 6 of ANSI Z136.1 .5Nominal Hazard Zone (NHZ) .6Optical Density .6Barrier Separation Distance.6Miscellaneous Equations .7Quantities and Units: Laser Safety Equation Sheet .8

Board of Laser Safety Certified Laser Safety Officer ProgramExamination Reference GuideGeneral InformationIn achieving certification, the Certified Laser Safety Officer (CLSO) recognizes andassumes the responsibilities due to the practice of laser safety. As a requirement of beingcertified, such persons act professionally, safely and in accordance with the Code ofProfessional Conduct. Each certificant has a professional and ethical obligation topractice only in those areas of laser safety in which he or she is competent. The CLSOhas a commitment to remain professionally active in the field of laser safety bymaintaining certification. As the industry and technology changes, so must theknowledge of the CLSO.This guide is intended to help candidates prepare for the CLSO examination by givingthem references for each section of the exam. However, use of the guide by itself will notbe adequate preparation for the exam.The references given in this guide are intended to provide candidates with referencematerial related to the general topics covered in the exam. This does not mean to implythat study of these references, only, will ensure successful performance on theexamination. This listing is by no means complete; candidates may need to consultadditional reports, journals and text books for information not provided in the referencesbelow.At the same time, not all of these references are necessary to successfully complete theexamination. They are provided as a guide to the type of material that should be studied.Information regarding requirements for certification, exam dates and locations, andapplications and fees are available from:Board of Laser Safety13501 Ingenuity Drive, Suite 128Orlando, FL 32826407.985.3810 or 800.345.2737FAX: 407.380.5588Email: [email protected]: http://www.lasersafety.orgCaution - The information in this guide about the exam and other matters are believed to becorrect at the time of publishing; however, the candidate is advised to review the current copy ofthe CLSO Policies and Procedures Manual.1BLS Examination Reference GuideApril 2013 Revision

Examination InformationThis examination is multiple-choice, consisting of 100 questions. Each question has apossibility of five (5) answers. Some answers require calculations. Here are a few issuesto consider prior to beginning the examination:1. Allow yourself time to answer all questions.2. Answer the questions you are sure of first, then go back and answer theremaining ones.3. Answer all questions, even if you are unsure of the answer. An educatedguess is better than no guess at all.4. If you are unsure of an answer, your first instinct is usually the correct one.There are nine (9) areas of practice on the subject matter of laser safety. To assist you inunderstanding the subject matter, the areas of practice and what percentage they representon the exam are provided here.Area of Practice I – Lasers & Optics Fundamentals – 11%Area of Practice II – Laser/Optical Radiation Bioeffects – 11%Area of Practice III – Non-beam Hazards Associated with Lasers – 8%Area of Practice IV – Laser Control Measures – 17%Area of Practice V – Regulations and Standards – 14%Area of Practice VI – Hazard Evaluation & Classification – 15%Area of Practice VII – Maximum Permissible Exposures (MPE) – 11%Area of Practice VIII – Laser Safety Program Administration – 10%Area of Practice IX – Laser Measurements – 3%In general, the following reference materials should be obtained or reviewed, as theycontain information included in most, or all, of the areas of practice:1. ANSI Z136.1 (2007), American National Standard for Safe Use of Lasers, LaserInstitute of America, Orlando, FL.2. Safety with Lasers and Other Optical Sources, Sliney, D. and Wolbarsht, M.,Plenum, New York, NY, 1980.2BLS Examination Reference GuideApril 2013 Revision

Other Hard Copy Materials1. CLSO’s Best Practices in Laser Safety, Laser Institute of America, Orlando, FL,2008.2. Laser Radiation, Hitchcock, R.T. and R.J. Rockwell, Jr., American IndustrialHygiene Association, Fairfax, VA, 1999.3. Laser Safety, Henderson, R. and Schulmeister, K., Institute of Physics Publishing,Bristol, UK and Philadelphia, PA, 2004.4. Laser Safety Guide, Marshall, W. and Sliney, D. (editors), Laser Institute ofAmerica, Orlando, FL, 2007.5. Laser Safety Management, Barat, K., CRC Press, New York, NY, 2005.6. Laser Safety: Tools and Training, Barat, K., CRC Press, New York, NY, 2008.7. LIA Guide for the Selection of Laser Eye Protection, Sliney, D. (editor), LaserInstitute of America, Orlando, FL, 2007.8. Marshall, W.J., “Understanding laser hazard evaluation,” J Laser Appl. 7:99-105(1995).Web Pages and Free Online Tutorials1. Food and Drug Administration: 21 CFR /cfdocs/cfcfr/cfrsearch.cfm2. Indiana University-Purdue University Indianapolis: Online Laser Safety Training(guest registration afety home.asp3. Occupational Safety and Health Administration: Safety and Health Topics,Laser Hazards Princeton University: Laser Safety Training /index.htm5. Sam’s Laser FAQ: Laser ftoc6. Sam’s Laser FAQ: What is a Laser and How Does It wil7. The Physics Classroom: Anatomy of the L6a.html8. The Physics Classroom: Specular vs. Diffuse fln/U13L1d.html3BLS Examination Reference GuideApril 2013 Revision

9. University of California, Berkeley: Laser Safety Training Supplement phylabs/adv/LaserSafeTrainSup04.pdf10. University of North Carolina: Laser Safety Training study/laser/11. U.S. Army CHPPM: Lasers and Their Effects on the Human ons/Fact%20Sheets/250130498.pdf4BLS Examination Reference GuideApril 2013 Revision

Laser Safety Equation SheetsSelected Maximum Permissible Exposures (MPEs)1.8t 0.75 10-3 J/cm2Visible region including 0.25 sec(from 18 10-6 to 10 sec exposure)C B 10-4 W/cm2Visible region (0.400 to 0.500 µm) including 600 sec(from 100 to 3 104 sec exposure)C A 10-3 W/cm2IR (0.700 to 1.050 µm) including 10 sec(from 10 to 3 104 sec exposure)5.0 C C 10-3 W/cm2IR (1.050 to 1.400 µm) including 10 sec(from 10 to 3 104 sec exposure)Correction Factors from Table 6 of ANSI Z136.1C A 102(λ-0.700)Reduced absorption by melanin (0.700 to 1.050 µm)C B 1020(λ-0.450)Blue light correction factor (0.450 to 0.600 µm)C C 1018(λ-1.150)Preretinal absorption (1.150 to 1.200 µm)C E α/α minExtended source, 0.400 to 1.400 µm, for α min α α maxC E α2/(α max α min )Extended source, 0.400 to 1.400 µm, for α α maxC P n-0.25Repetitive pulse correction factor (0.180 to 1000 µm)T 1 10 x 1020(λ-0.450)Replace thermal by photochemical MPE, 0.450 to 500 µmT 2 10 x 10(α -1.5)/98.5Time related to eye movement, 0.400 to 1.400 µm5BLS Examination Reference GuideApril 2013 Revision

Nominal Hazard Zone (NHZ)r NHZ (1/ϕ)[(4Φ/πMPE) – a2]1/2Direct viewing of laser beamr NHZ f o /b o (4Φ/πMPE)1/2Lens on laser (focused beam)r NHZ 1.7/NA (Φ/πMPE)1/2Fiber optics, multimode fiberr NHZ ω o /λ (πΦ/2MPE)1/2Fiber optics, singlemode fiberr NHZ (ρΦcosθ/πMPE)1/2Diffuse reflectionOptical DensityD λ log 10 (1/τ)Optical densityD λ log 10 (I o /I)OD for incident and transmitted intensityD λ log 10 (E o /MPE E )OD for MPE in terms of irradianceD λ log 10 (H o /MPE H )OD for MPE in terms of radiant exposureBarrier Separation DistanceD s (1/ϕ)[(4Φ/πTL) – a2]1/2Direct intrabeam exposureD s f o /b o (4Φ/πTL)1/2Lens on laser (focused beam)D s (ρΦcosθ/πTL)1/2Diffuse reflection6BLS Examination Reference GuideApril 2013 Revision

Miscellaneous EquationsQ ΦtRadiant energy and radiant power conversionH 4Q/πD L 2Radiant exposure for a circular beamE 4Φ/πD L 2Irradiance for a circular beamH EtRadiant exposure and irradiance conversionΦ peak Q p /tPeak power from pulse energy pulse lengthΦ avg Q p FAverage power from pulse energy and PRFn FtNumber of pulses from PRF and exposure durationD L (a2 ϕ2r2)Laser beam spot sized fϕFocused image diameterα D L cosθ/rViewing angle for a given spot size atdistance rr max D exit cosθ/α minMaximum distance for extended-source viewingϕ s/rPlane angle definition in radiansΩ A/R2Solid angle definition in steradiansG Do2 / De2Optical gainI 2 I 1 magnification2Increase in intensity with magnificationNOTE: The laser equation sheet is not intended to be comprehensive but includesequations that may be used often by practicing laser safety officers. Descriptions areintentionally concise; see ANSI Z136.1 for more complete descriptions. Also, somequantities may be scaled with a different multiple or submultiple prefix (e.g., micro- vs.milli-) than shown.7BLS Examination Reference GuideApril 2013 Revision

Quantities and Units: Laser Equation SheetSymbolQuantityUnitSymbolAaboDeD exitDLDλDoDsdEEoFf,f oGHHoIoIMPE EMPE HnNAr NHZrQQpsTLTtαλϕΦΦ avgΦ peakareaemergent beam diameterbeam diameter on lensdiameter of exit pupilexit port diameter of laserbeam spot sizeoptical densitydiameter of objectivebarrier separation distancediameter of focused spotirradianceincident irradiancepulse repetition frequencyfocal lengthgainradiant exposureincident radiant exposureincident intensitytransmitted intensityMPE as irradianceMPE as radiant exposurenumber of pulsesnumerical aperturenominal hazard zonedistance - radiusradiant energypulse energyarc lengthbarrier threshold limitpulse durationexposure durationviewing anglewavelengthbeam divergenceradiant poweraverage beam powerpeak beam powerviewing angle (normal & eye)reflectivitytransmittancesolid anglemode field diametersquare terwatts per square centimeterwatts per square centimeterhertzlengthdimensionlessjoules per square centimeterjoules per square centimeterwatts or watts / square centimeterwatts or watts / square centimeterwatts per square centimeterjoules per square oulescentimeterwatts per square z (s-1)cm--J/cm2J/cm2W or W/cm2W or W/cm2W/cm2J/cm2----cm--JJcmW/cm2s or secs or secmradµmmradWWWradθρ--τ--Ωsrωoµm8BLS Examination Reference GuideApril 2013 Revision

The mission of the BLS is to provide a means for improvement in thepractice of laser safety by providing opportunities for the education,assessment, and recognition of laser safety professionals.13501 Ingenuity Drive, Suite 128 Orlando, FL 32826407.380.1553 800.345.2737 Fax: [email protected]

In achieving certification, the Certified Laser Safety Officer (CLSO) recognizes and assumes the responsibilities due to the practice of laser safety. As a requirement of being certified, such persons act professionally, safely and in accordance with the Code of Professional Conduct. Each