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Transmittal Notice

  1. Explanation of Material Transmitted: This chapter establishes the scope and objectives of the National Institutes of Health (NIH) Laser Safety Program (LSP).  This chapter has been developed to provide guidance and oversight for the safe use of lasers and laser systems at the NIH.
  2. Filing Instructions
    Insert: Manual Issuance 3036 dated 4/7/2016.

PLEASE NOTE: For information on:

  • Content of this chapter, contact the issuing office listed above.

The Laser Safety Program (LSP) provides instruction for the safe use of lasers and laser systems at the National Institutes of Health (NIH).  The program applies to personnel working with or around laser systems and is administered by the Division of Occupational Health and Safety (DOHS), Office of Scientific Resources (SR), Office of Research Services (ORS).

Laser systems are incorporated into a variety of research methods and research protocols. Examples of laser system applications include: The destruction of matter during the cross linking of DNA proteins, retinal photocoagulation, laser embedded confocal microscope systems, optogenetic investigations of motivational circuits, manipulation of the firing of neurons in targeted brain regions, and heat ablation of tumors, among others. Laser system use has increased and has become refined enabling the use of smaller laser units with more powerful output.  The NIH, recognizing that the use of laser systems in scientific research will continue to advance, is committed to the safe use and operation of this equipment.

The LSP was established to minimize hazards associated with the use of Class 3b and 4 lasers and laser systems.

The LSP is based on recommendations from American National Standards Institute (ANSI) Z136.1-2014 and other consensus guidelines (see Section 4).  The instructions outlined herein shall not be intended to restrict or limit the use of laser radiation, which may be intentionally administered to an individual for healthcare applications, including diagnostic, aesthetic, preventative, therapeutic, or medical/dental research.

The LSP requires appropriate training for users; maintenance of an inventory of Class 3b and 4 lasers and laser systems; annual surveys of Class 3b and 4 lasers and laser systems; and response to accidents and incidents involving lasers and laser systems.

D. Laser Classification

  1. Class 1
    1. Understood to be a non-hazardous source when used as intended by the manufacturer.
    2. Not subject to the requirements of the LSP.
  2. Class 1M
    1. A Class 1 system that may become hazardous if viewed with an optical instrument.
    2. Not subject to the requirements of the LSP.
  3. Class 2
    1. A laser with power less than or equal to 1 milliwatt.
    2. A laser within the visual spectrum (400 nanometers – 700 nanometers).
    3. Not subject to the requirements of the LSP.
  4. Class 2M
    1. A Class 2 system that may become hazardous if viewed with an optical instrument.
    2. Not subject to the requirements of the LSP.
  5. Class 3R
    1. A laser with power less than 5 milliwatts.
    2. May be dangerous from both direct viewing and specular reflections if natural aversion responses are not functioning properly.
    3. Not subject to the requirements of the LSP.
      1. Control measures: Ensure no optically aided viewing is used.
  6. Class 3b
    1. Lasers above 5 milliwatts, but not exceeding 500 milliwatts radiant power.
    2. May be dangerous from both direct viewing and specular reflections.
    3. Not a fire hazard.
    4. Subject to the provisions of the LSP.
      1. At a minimum, an annual survey is required for compliance with the LSP.
      2. Control measures: See Section F. Laser Hazard Control Measures for more information regarding specific control measures.
  7. Class 4
    1. A laser with power that exceeds a Class 3b.
    2. Hazardous to both eyes and skin when beam makes direct contact or from specular reflection.
    3. May be a fire hazard.
    4. Subject to the provisions of the LSP.
      1. At a minimum, an annual survey is required for compliance to the LSP.
      2. Control measures – See Section F. Laser Hazard Control Measures for more detailed information regarding specific control measures.
    Note:  Under certain circumstances a laser that is classified as a Class 3b or Class 4 laser can be downgraded to a Class 2 or Class 1 laser, if the appropriate engineering controls and safety controls have been incorporated.  The downgrade of a system will be determined by the Laser Safety Officer (LSO) through discussion with the laboratory manager and an accompanying site visit to confirm appropriate controls are in place.

E. Laser Acquisition and Transfer

It is the responsibility of the Principal Investigator (PI) to document and report to the Laser Safety Advisory Committee (LSAC) and the DOHS, the purchase or possession of Class 3b or 4 lasers or a laser system.  The PI may choose to delegate this function; however, the ultimate responsibility for reporting remains with the PI. Required registration information is located in Appendix A, specifically, sections labeled laser information and technical specifications.  These two sections within Appendix A must be completed and a copy of this form should be submitted to the Laser Safety Advisory Committee, NIH, Building 13, Room 3K04 or sent via email to

F. Laser Hazard Control Measures

Controls for Class 3b and Class 4 Lasers:

  1. Authorization – Only individuals who have been trained by the DOHS (or a designated representative) are authorized to use a Class 3b or 4 laser. 

  2. Beam trajectory and control – Beam trajectory and alignment may be performed by a trained NIH laser user or appropriately trained third party personnel.  Due to the increased risk associated with this process, parties performing beam trajectory and/or alignment must follow appropriate safety precautions, which include:

    • Reduction of speculative surfaces
    • Removal of all jewelry which has the potential to come into contact with the beam
    • Placing the laser in alignment mode (where available)
    • Operating the laser at the lowest achievable power during alignment to reduce risk
    • Wearing of appropriate personal protective equipment (PPE)
    • Incorporation of interlock switches, beam stops, protective barricades
    • Restricted access to the laser location

    The laser beam should be aligned at a height that does not expose an individual.   As such, standing and sitting heights must be taken into consideration when aligning the laser beam.  Additionally, an appropriate beam stop must be utilized to terminate the beam.  The laser may only be utilized after the beam trajectory has been well characterized and understood.   

  3. Containment – All Class 3b and 4 lasers, and laser systems, must fully enclose the beam path and potential reflections of the beam off of surfaces.  Building materials should be analyzed for reflective potential and when possible altered to decrease reflectance to as low as reasonably achievable. Windows in the laser area must be removed or covered to block transmission of the beam.  Engineering controls (e.g. laser activation entry lights and key switches) must be used at all times to ensure effective containment and control of the laser beam.

  4. Non-beam hazards – All non-laser materials that have the potential to cross the beam path must be assessed to determine if any hazards are created upon contact (e.g fire, fumes, vapors).  In the absence of a complete hazard assessment, the PI should assume a hazardous by-product and ensure a proper means to eliminate the hazard. The most common means of controlling non-beam hazards is the use of local exhaust ventilation.  Additional non-beam hazards are described in Section G.

  5. Posting – At a minimum, the entryway into a room containing a laser or laser system shall be posted with a warning sign to identify the class of laser, laser power, required personal protective equipment, and laser wavelength(s).  Additionally, it may be necessary to post warning signs inside the laser safety area to further define the hazard.

  6. Personal Protective Equipment (PPE) – Appropriate PPE must be worn by operators and personnel at risk of beam exposure. The most common PPE worn when working with lasers is protective eyewear.  It is critical that the eyewear be appropriate to the laser class and provides sufficient protection from the wavelengths associated with the laser or laser system.  All PPE must be inspected before use for conditions that would reduce or negate the effectiveness of the protective equipment.

  7. Rapid Egress and Emergency Access – All Class 4 laser area(s) must have a controlled means of rapid egress and admittance for emergency conditions.  At a minimum, a 28 inch clearance pathway shall be maintained within the laboratory leading to the exit doorway.

G. Laser Related Non-Beam Hazards and Control Measures

  1. Electrical Hazards – Many incidents related to laser(s) and laser system(s) stem not from the laser beam, but from user interaction with electrical components associated with the laser or laser system.  Most Class 3b and 4 lasers utilize high voltages and capacitors that increase the risk for electrical injury.  Only users trained in lockout / tagout and electrical safety should be authorized by the PIs to work with exposed electrical components. Any work involving electrical components must comply with the NIH Lockout/Tagout procedures.

  2. Laser Dyes – Dyes used as lasing mediums are often classified as toxic, carcinogenic and/or flammable.  These chemicals must be handled appropriately as defined in the product’s safety data sheets and in accordance with the NIH Hazard Communication Program. Safety data sheets for chemicals used in the laboratory must be on file within the laser use area.

  3. Laser Generated Air Contaminants (LGAC) – Contact between a laser beam and a material can cause specific, yet sometimes unknown contaminants to be released into the atmosphere.  The release of air contaminants may occur without noticeable signs, such as smoking or odor.  Proper room ventilation or local exhaust ventilation is critical in any laser use area, and must be evaluated before the installation of a Class 3b or 4 laser.  The use of respiratory protection is not a recommended means of controlling the generated airborne hazard.

  4. Ultra Violet, Visible-Radiation and Plasma Emissions – Evaluations for the discharge of radiation, including both visible and ultraviolet; plasma formation must be completed before the use of a Class 3b or 4 laser.  Identification of emissions requires a review of the selected PPE to minimize exposure and injury.  Additionally, laser and laser system components must be periodically surveyed by the laser user for damage.

H. Laser Safety Advisory Committee (LSAC)

The LSAC shall be made up of the LSO and at least one representative from each Institute/Center operating a Class 3b or Class 4 laser(s) and or laser systems. 

I. Laser Safety Training

All supervisors and users must successfully complete the NIH laser safety training before using a Class 3b or Class 4 laser or laser system.  Completion of an alternate training class must be submitted to the LSAC for approval.  Retraining is required every year after initial training.  Additional training may be required of laser users, prior to the above timeframe if, a near miss occurs, competencies are not met, or if a circumstance requires it.

J. Laser Safety Survey

An annual laser safety survey is required for all Class 3b and Class 4 lasers and laser systems.  Safety surveys can be completed by the LSO or a representative designated by the LSO. The laser safety survey form is attached (Appendix A). The PI or their designee will identify and implement corrective actions in a timely manner to resolve deficiencies noted during the safety survey.  Use of laser(s) or laser system(s) shall not continue until corrective actions are made unless the LSAC grants a written waiver to the PI.

K. Laser Accidents

In the event of an accident or incident involving a Class 3b or 4 laser or laser system, the user must immediately notify his/her supervisor.  The user must undergo an immediate medical evaluation by the Occupational Medical Service (OMS), which is located on the sixth floor of Building 10, Room 6C306; telephone number: (301) 496-4411.

NIH Manual 1743 – Keeping and Destroying Records

Note:  The below ANSI Standard document information can be obtained by calling DOHS at 301-496-3353

ANSI Z136.1-2014, American National Standard for Safe Use of Lasers

ANSI Z136.8-2012, American National Standard for Safe Use of Lasers in Research, Development, or Testing

ANSI Z136.3-2011, Safe Use of Lasers in Health  Care  Facilities

29 CFR 1910.132, Personal protective equipment

29 CFR 1910.133 (a), Eye and face protection

OSHA Technical Manual:  Laser Safety

21 CFR 1040.10, Laser Products

21 CFR 1040.11, Specific purpose laser product

HHS Publication FDA 86-8260, Compliance Guide for Laser Products

NIH Hazard Communication Program

M. Definitions

  1. Accessible emission limit (AEL):  The maximum accessible emission level permitted within a particular laser hazard Class.

  1. Authorized personnel:  Any individual approved to work with a laser or laser system.

  1. Aversion response:  An involuntary movement of either the head and /or eye to avoid exposure to a visible laser beam.

  1. Blink reflex:  The involuntary closing and opening of the eye(s) as a result of external stimulation.

  1. Collecting optics:  Lenses or optical instruments that use magnification to increase the power of a laser beam.

  2. Continuous wave (CW): A laser beam with an output pulse width greater than 0.25 seconds.

  3. Diffuse reflection:  The reflecting of a laser beam in many directions by a surface.

  4. Divergence: The splitting of a laser beam so that the beam diameter increases with distance traveled.

  1. Embedded laser:  A laser of a specific Class that is reduced to a lower Class due to the mechanisms and devices (engineering controls) that remove potential for contact or exposure.

  1. Fail-safe interlock:  An engineering control where the failure of a single mechanical or electrical component of the interlock will cause the system to go into, or remain in, a safe mode.

  1. Infrared:  In this standard, the region of the electromagnetic spectrum between the long- wavelength extreme of the visible spectrum (about 0.7 m) and the shortest microwaves (about 1 mm).

  1. Intrabeam viewing:  The viewing condition whereby the eye is exposed to all or part of a laser beam.

  1. LSAC:  Laser Safety Advisory Committee

  1. LSO:  Laser Safety Officer

  1. LSP:  The NIH Laser Safety Program

  1. Maximum permissible exposure (MPE):  The level of laser radiation to which an unprotected person may be exposed without adverse biological changes in the eye or skin.

  1. Nominal hazard zone (NHZ): The space within which the level of the direct, reflected, or scattered radiation may exceed the applicable MPE. Exposure levels beyond the boundary of the NHZ are below the appropriate MPE.

  1. Non-beam hazard:  A Class of hazards that result from factors other than direct human exposure to a laser beam.

  1. Protective housing:  An enclosure that surrounds the laser or laser system and prevents access to laser radiation above the applicable MPE. The aperture through which the useful beam is emitted is not part of the protective housing. The protective housing limits access to other associated radiant energy emissions and to electrical hazards associated with components and terminals, and may enclose associated optics and a workstation.

  1. Pulsed laser:  A laser which delivers its energy in the form of a single pulse or a train of pulses. In this standard, the duration of a pulse is less than 0.25 s.

  1. Q-Switch: A technique by which a laser can be made to produce a pulsed output beam. The technique allows the production of light pulses with extremely high (gigawatt) peak power, much higher than would be produced by the same laser if it were operating in a continuous wave (constant output) mode.

  1. Q-switched laser:  A laser that emits short (~10-250 ns), high-power pulses by means of a Q- switch.

  1. Safety latch:  A device intended to provide a measure of safety that must physically be removed to allow exposure to a hazard.

  1. Specular reflection:  A mirror-like reflection.

  1. Thermal effect:  Temperature elevation caused by exposure to a laser beam.

  1. Threshold limit (TL):  The term is applied to laser protective eyewear filters, protective windows, and barriers. The TL is an expression of the resistance factor for beam penetration of a laser protective device.  This is generally related by the TL of the protective device, expressed in W cm-2 or J cm-2. It is the maximum average irradiance or radiant exposure at a given beam diameter for which a laser protective device provides adequate beam resistance. Thus, laser exposures delivered on the protective device at or below the TL will limit beam penetration to levels at or below the applicable MPE.

  1. Ultraviolet radiation:  In this standard, electromagnetic radiation with wavelengths between 180 nm and 400 nm (shorter than those of visible radiation).

  2. Wavelength:  The distance in the line of advance of a sinusoidal wave from any one point to the next point of corresponding phase (e.g., the distance from one peak to the next).

N. Responsibilities

  1. Director, NIH
    1. Through DOHS and the Deputy Director for Intramural Research (DDIR), provide executive leadership in the development and implementation of biological safety policies, standards and procedures applicable to the NIH. The DOHS provides staff necessary to effectively administer a comprehensive occupational safety and health program.
  2. Deputy Director for Intramural Research (DDIR)
    1. The DDIR is the principal liaison with the NIH intramural research community regarding safety and health matters.
    2. Receive safety policies approved by ORS and communicate them to the IC Scientific Directors.
    3. Raise safety concerns to ORS as they are brought to the DDIR’s attention from the intramural research community.
  3. Designated Agency Safety and Health Official (DASHO)
    1. The Institutional Official responsible for management and administration of the NIH occupational safety and health program. This authority is delegated by the Director, NIH.
  4. Laser Safety Advisory Committee (LSAC)
    1. Laser safety program development and management;
    2. Verification of safety practices within laser laboratories using laser(s) or laser system(s);
    3. Investigation of incidents and accidents involving the use of lasers in NIH facilities;
    4. Maintain an accurate inventory of Class 3b and 4 laser(s) and laser system(s).
    5. Quarterly meetings
  5. Laser Safety Officer (LSO)
    1. The laser safety officer will be appointed by the NIH, DOHS;
    2. Provide clarification regarding classification of laser(s) and laser system(s);
    3. Develop and conduct laser safety training;
    4. Determine necessary safety information (evaluation and control measures) critical for the implementation of a laser laboratory as specified by ANSI Z136.-2014 American National Standard for Safe Use of Lasers and compliance to applicable laws;
    5. Provide information concerning the purchase of necessary laser safety materials (signs, labels, safety eyewear, etc.);
    6. Monitor and enforce program requirements; and
    7. Conduct periodic review of the Laser Safety Program.
  6. Supervisors/ Principal Investigators (PI)
    1. Submit a registration email to the LSO for all Class 3b and Class 4 laser(s) or laser system(s) with the following information; new laser location(s), institute, and contact information.
    2.   Identify all laser hazards and implement all appropriate hazard controls.  If found, correct any identified unsafe or non-compliant conditions in the laboratory;
    3. Identify all personnel who may operate or maintain a Class 3b or Class 4 laser(s) or laser system(s).  Ensure proper initial training and subsequent yearly refresher training for these authorized personnel;
    4. Monitor all authorized personnel for compliance with the Laser Safety Program;
    5. Ensure that laser(s) and laser system(s) are maintained adequately to ensure proper working order;
    6. Maintain a copy of the Laser Safety Program in the workplace.
  7. Laser User
    1. Attend required training(s) as specified by a supervisor, LSO, or LSAC;
    2. Know all laboratory hazards and laboratory procedures for the safe use of lasers and laser systems in the work area;
    3. Complete all aspects of laser usage in accordance with the laser safety program and good safety practices;
    4. Use all personal protective equipment as specified in prescribed training or required by a supervisor, LSO, or LSAC;
    5. Immediately notify a supervisor, LSO, or LSAC of any hazards encountered.  Report to OMS if an injury or suspected injury has occurred

All personnel associated with a laser or laser system shall comply with the elements set forth within this NIH manual chapter. All actions below (excluding #3) must be completed using the NIH Laser Safety Application.  Access to the laser application will be granted by the LSO or a DOHS representative and can be reached at 301-496-3353 or deptolamr@mail.nih.govAs previously stated, the following procedures must be followed when using a laser system:

  1. Completion of a standard operating procedures (SOP) document that is specific to the laboratory/laser location.  This information shall be posted outside on the door outside of the room accessible to the laser or laser system (The SOP appendix can be found within the current laser safety program).

  2. All personnel who use lasers shall successfully complete annual laser safety training.

  3. An inventory of lasers must be maintained by an appointed Institute/Center representative.

  4. Laser purchases shall be communicated to the IC safety representative and to DOHS prior to use.

  5. A yearly update of the laser profiles within the database shall be completed by the laser users in order to help identify changes in laser users and laser systems.

P. Records Retention and Disposal

NIH Manual 1743,"Keeping and Destroying Records," Appendix 1, "NIH Records Control Schedules" (as amended). These records must be maintained in accordance with current NIH Records Management and Federal guidelines. Contact your IC Records Liaison or the NIH Records Officer for additional information.

Q. Internal Controls

The LSP has been developed to provide guidance and oversight for the safe use of lasers and laser systems at the NIH.  The Laser Safety Program applies to all NIH employees, visitors, contractors and students working at official NIH facilities.

  1. Office Responsible for Reviewing Internal Controls:  The DOHS has the operational responsibility for the NIH LSP.  The DOHS provides oversight of the program, and serves as the liaison between the program and NIH management.

  2.  Frequency of Review (in years): Ongoing.

  3. Method of Review:  The DOHS will maintain oversight and ensure effective implementation and compliance with this policy through: Conducting inspections of laboratories in which lasers and laser systems are used; following up on any items of non-compliance; tracking training data to ensure all individuals working with lasers have been trained; tracking standard operating procedures received by laser labs; performing injury investigations related to laser use; and updating policies as needed in response to changes in requirements of the ANSI Standards, U.S. Department of Labor, and the U.S. Food and Drug Administration.  The DOHS uses a comprehensive, custom-designed database to demonstrate compliance with the NIH Laser Safety Program.

Appendix A. Laser Safety Program Survey Form

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