Exam Structure & Studying:

Currently, BLS offers two certifications: Certified Laser Safety Officer (CLSO) and Certified Medical Laser Safety Officer (CMLSO). It’s important to study for these exams, as experience  and training alone may not cover all areas of practice found on the exams. These exams are based on the relevant American National Standard for their industry, which should serve as your primary study materials.

  CLSO Exam CMLSO Exam
Areas of Practice 9 8
Number of Questions 100 100
Question Types Multiple Choice Multiple Choice
Number of Answer Choices 5 4
American National Standard ANSI Z136.1 – 2014 ANSI Z136.3 – 2011
Time Allotted for Exam 3-hours 3-hours
Hazard Calculations Yes No


A detailed breakdown of the areas of practice of each exam can be found in the exam reference guides. Many candidates use this information to guide their studying efforts:

Day of the Exam:

Each candidate must provide a valid form of legal ID (State ID, Driver’s License, Passport), and a copy of their letter of acceptance on the day of the exam. The only materials allowed during the exam will be provided by the proctor, with the exception of a non-programmable scientific calculator, which CLSO candidates may bring if they choose; equation sheets are prohibited. Study materials are not allowed during either exam. Proctors will provide pencils for paper-and-pencil exams.

Dual Certification

Candidates may apply for both exams; however, each exam requires its own application, references, and fees, and the candidate will only be approved to sit for exams that he/she has met all eligibility requirements for. Maintaining both certifications requires that the candidate earns 10 BLS CM points for each certification over each 3-year certification cycle. For additional information on certification maintenance, please see the relevant Certification Maintenance Manual or contact the BLS office.