IDAHO STATE UNIVERSITY
LASER SAFETY Policies and Procedures
Prepared by:
The LASER Safety Committee
Idaho State University
Campus Box 8106
Pocatello, Idaho 83209
(208) 282-2310
December 20, 2002
Approved By:
(signatures on file in TSO)
Director, Technical Safety Office
Vice President for Academic Affairs
This document was prepared for use within Idaho State University
(ISU). It is intended for use by, and applies to ISU employees, staff,
visitors, and students. If this document or any portion of it is
used elsewhere, neither its authors nor the University accept responsibility
for its contents.
Statement of Recognition
This Policy has been adopted in large part from the
Purdue University LASER Safety Policy
with permission.
This information may not be used for commercial development
or profit.
PREFACE
The purpose of this manual is to provide individuals using lasers information on laser hazards, laser-related policies and procedures, recommendations for the safe use of lasers, and laser safety training. It has been designed to provide the basis for safe laser use in the research and teaching environment without placing excessive burdens of cost or use restrictions on those responsible for laser operations. Much of the information contained herein is based on the American National Standard for Safe Use of Lasers, ANSI Z136.1-2000 and ANSI Z136.5-2000. The ANSI standard is the accepted standard for laser safety in the United States.
Many lasers are capable of causing eye injury to anyone who looks directly into the laser output beam, or even at a specular reflection of the beam. In addition, diffuse reflection of a high-power laser beam can produce permanent eye damage. High-power laser beams can also burn exposed skin, ignite flammable materials, and cause the release of hazardous fumes, gases, and debris. Other hazards associated with the equipment and optical apparatus required to produce the lasing action and control the beam can include high-voltage, high pressure, compressed gases, cryogenics, noise, ionizing and non-ionizing radiation, and toxic materials.
Despite the potential hazards, laser equipment can be operated safely if the proper procedures and necessary precautions are followed. To this end, the Idaho State University Laser Safety Committee has adopted this manual. If you need additional information or assistance, contact the Idaho State University Laser Safety Officer at the ISU Technical Safety Office (TSO), phone 282-2310/2311/3669.
CHAPTER 1. INTRODUCTION TO LASER SAFETY AT IDAHO STATE UNIVERSITY
Is my laser dangerous?
I have a class 3b or 4 laser. What makes it dangerous to me?
What is the danger to me?
How do I know how much is too much?
How can I avoid accidental exposure?
Where can I get more laser safety information at Idaho State
University?
Laser safety information is available in this booklet, at the website
http://www.physics.isu.edu/health-physics/tso/lasersafety.html, and through
the TSO.
Where can I find out about procedures at Idaho State University?
Procedures for the safe operation of a laser can be found in the next
two chapters of this booklet. In Chapter 2 we discuss safety features
that should be designed into the laser and the laboratory, as well as information
on procedural and administrative policies.
Procedures at Idaho State University are based on many of the guidelines developed by professional organizations such as the American National Standards Institute (ANSI). Several sections of the American National Standard for Safe Use of Lasers, ANSI Z136.1 and ANSI Z136.5, are referenced in the following sections and are denoted by parenthesis. The ANSI Standard and other laser safety references are available from the TSO for checkout.
CHAPTER 2. CONTROL MEASURES
I. Introduction
Control measures for Class 3b and 4 lasers are designed to reduce the
possibility of eye and skin exposure to hazardous levels of radiation and
to other hazards associated with the laser systems. The major causes
of laser accidents in the laboratory are:
Control measures are classified as engineering control measures
(ANSI Z136.1 sec. 4.3) and administrative and procedural control measures
(ANSI Z136.1 sec. 4.4 and 4.5). Engineering controls are those that
are incorporated into the laser system and the laser laboratory.
Administrative and procedural controls are methods or instructions which
specify rules and/or work practices to supplement engineering controls
and may require use of personal protective equipment. An example
of an engineering control measure would be a laser beam stop, and an example
of an administrative and procedural control measure would be the SOPs.
When feasible, engineering controls are always the preferred method to
provide for safety in a laser laboratory.
Laser controls are designed to ensure skin and eye exposures do not exceed the applicable Maximum Permissible Exposure (MPE) limit. The MPE defines the maximum safe exposure without hazardous effect or adverse biological changes in the eye or skin. The MPE depends upon the wavelength and exposure duration.
An important consideration when implementing control measures is to
distinguish among operation, maintenance, and service. Control measures
are based on normal operation of the laser system. When either maintenance
or service is performed, it is often necessary to implement additional
control measures.
II. Engineering Controls
Engineering controls for Class 3b and 4 lasers are listed below. All Class 3b and 4 lasers at Idaho State University are covered by this policy, and should have the listed design features unless otherwise approved by the Laser Safety Officer (LSO). If the system is purchased in the United States, the system has as part of the design features the controls stated below. This is often indicated on the laser by a “statement of certification”.
III. Administrative and Procedural Controls
IV. Class 3b and 4 Laser Controlled Area
A. The area designated as the controlled area for Class 3b laser facilities
shall have the following adequate control measures (ANSI Z136.1 sec. 4.3.10.1).
V. Equipment Labels
All lasers (except Class 1) shall have appropriate warning labels with the laser sunburst logo and the appropriate cautionary statement (Figure 1). The labels shall be affixed to both the control panel and the laser housing.
Ancillary hazards shall also be appropriately labeled, but the sunburst logo is not required.
VI. Area Posting Signs
Areas which contain Class 2 or 3a laser systems should be posted with appropriate area postings as described in Figure 3. Areas which contain Class 3b or 4 laser systems shall be posted with appropriate area postings as described in Figure 4. Also, the laser controlled area should be indicated with the appropriate warning sign.
Image Not Available
Figure 3. Area Posting for Class 2 and 3a Lasers
Image Not Available
Figure 4. Area Posting for Class 3b and 4 Lasers
CHAPTER 3. LASER SAFETY PROGRAM
This chapter was developed to inform supervisors and operators of their roles and responsibilities to help provide a safe laser environment at Idaho State University.
I. RESPONSIBILITY OF EMPLOYEES AND STUDENTS WORKING WITH OR NEAR LASERS
A. Authorization
An employee or student shall not operate a class 3b or 4 laser system unless authorized to do so by the LPI for that laser. The LPI may give system specific laser safety training, including this document, and grant temporary permission to use the laser, provided that official authorization is completed within 2 months after use of the laser begins. Individuals are officially authorized to use laser systems upon completing training, demonstrating competency, and submitting an application (Appendix 3).
B. Compliance
All employees and students shall comply with the safety rules and regulations prescribed by the LPI, LSO, and Laser Safety Committee (LSC). Employees and students shall know the operating procedures applicable to their work.
C. Accident Reporting
All injuries and accidents involving lasers and laser systems shall be reported to the LPI and the LSO. However, the treatment of injured personnel and the preservation of property shall be the first priority.
II. RESPONSIBILITY OF THE LASER PRINCIPLE INVESTIGATOR
A. Prerequisite
The LPI shall know the educational and training requirements, the potential laser hazards and associated control measures, and all OPERATING procedures pertaining to laser safety for lasers and laser systems under the LPI’s control. Generally the LPI is a faculty member in charge of one’s laser facility.
B. Training
The LPI shall ensure that all laser users under his/her control are trained. Training material should include a broad understanding of hazards and controls for all lasers or all hazard classifications, especially those of class 3b and 4, the biological effects of lasers, the laser classification system, protective equipment, and administrative controls (ANSI Z136.5 sec 5.5.4).
C. Authorized Users of Laser Systems
The LPI shall determine which students and employees are authorized (Appendix 3) to operate a laser system under his/her control. The LPI may grant temporary permission to use the laser, if system specific laser safety training and this document are provided before use. Official authorization must be completed within 2 months after use of the laser begins. Individuals are officially authorized to use laser systems upon completing training, demonstrating competency, and submitting an application to the TSO (Appendix 3).
D. Accidents and Injuries
The LPI shall notify the LSO of known or suspected laser-related accidents and injuries. The LPI shall ensure that their departmental business office is promptly notified. If necessary, the LPI will assist in obtaining appropriate medical attention for any employee or student involved in the laser accident. The LPI shall cooperate with the LSO and/or LSC during the course of their investigation and implement recommendations to prevent a recurrence. A written incident report shall be prepared by the LPI within 1 month.
E. Approval of Laser System Operation
The LPI shall not permit operation of a new, modified or manufactured class 3b or 4 laser under his/her authority without prior written approval of the LSO or the LSC.
F. Approval of Planned Installations
The LPI shall assure that plans for laser installations or modifications of installations are submitted to the LSC for approval. The LSO will act as a consultant, in conjunction with Facilities Planning, for the installation of new laser facilities.
G. Operating Procedures
For Class 3b and 4 laser systems, the LPI shall ensure standard operating procedures (SOPs) are developed and provided in order to prevent the operation of a laser if exposure to employees, students, visitors, or the general public could exceed the MPE. SOPs shall also be necessary for alignment, maintenance and/or service, and emergency response.
III. RESPONSIBILITY AND AUTHORITY OF LASER SAFETY COMMITTEE
A. Policies and Practices
The committee shall establish and maintain policies, procedures, and guidance for the control of laser hazards. Refer to Appendix 5, Idaho State University President’s Executive Memorandum.
B. Approval of Class 3b and 4 Laser Facility
Approval of a laser or laser system for operation will be given only if the LSC is satisfied that the laser hazard control measures are adequate. These include standard operating procedures (SOPs), engineering controls for the laser, engineering controls for the laboratory or area, and administrative and procedural controls for the laser facility. Standard operating procedures for alignment, maintenance and/or service, and emergency response shall be provided as necessary.
Temporary approval for operation can be given by the LSO, who will then seek final approval at the next LSC meeting.
C. Standards
The committee will review all applicable new or revised laser safety standards.
D. Membership of Laser Safety Committee
The Idaho State University Laser Safety Committee shall consist of faculty and staff who by their knowledge and experience are qualified to make judgements and recommend policy in the area of laser safety. Committee members shall be appointed by Vice President of Academic Affairs in consultation with the various deans, directors, and department heads.
E. Authority
The LSC and the LSO have the authority to suspend, restrict, and terminate
the operation of a laser project if it is deemed that the laser hazard
controls are inadequate.
IV. RESPONSIBILITY AND AUTHORITY OF LASER SAFETY OFFICER
A. General
The LSO will work with the individual LPI to ensure the safety standards of each laser laboratory are adequate. The LSO shall be appointed by the Vice President for Academic Affairs and has the authority to monitor and enforce the control of laser hazards and to effect training of personnel involved with the use of laser technology and applications.
B. Consultative Services
The LSO will provide consultative services on laser classification, hazard evaluation and controls, procedure approval, and personnel training programs.
C. Training Programs
Training shall be provided to each employee and student routinely operating a Class 3b or 4 laser or laser system. The level of training will be commensurate with the degree of potential laser hazards. A comprehensive laser safety program is available from the TSO. Other training programs are encouraged. The LSC should be informed of the content of these alternative programs. Training should be completed at the time work begins, but no later than 2 months subsequent to initiation of work.
D. Records
The LSO will ensure that the appropriate records are maintained indicating that appropriate training has been provided and all users of laser systems are listed on the appropriate projects.
The LSO shall periodically contact the LPIs to ensure the laser application is current.
E. Surveys and Inspections
The LSO will survey all areas where Class 3b and 4 laser equipment is used. Surveys shall be performed on a regular basis, when modifications to the laser and/or laser system have occurred, before the initial operation of a new laser, or as deemed necessary.
Items reviewed during the survey include but are not limited to protective equipment, signs and labels, equipment, safety features (interlocks, etc.), and training records.
The LSO will accompany regulatory agencies inspecting the laser facility. The LSO will ensure that corrective action is taken where required.
F. Accidents and Injuries
Upon notification of a known or suspected laser-related accident or injury, the LSO shall investigate the accident or injury and take appropriate action. The LSO shall perform a hazard evaluation of the laser facility to determine the cause of the accident, interview individuals involved in the accident, and make certain that necessary controls have been implemented before operation resumes.
V. RESPONSIBILITY OF PURCHASING DEPARTMENT
The Idaho State University Purchasing Department will inform the LSO
of all orders for lasers and laser systems. Notification should be
in the form of a copy of the Purchasing Requisition. The LSO will
contact the LPI to determine if the appropriate laser safety controls are
in place, and to help remedy any problems or deficiencies. The LSO
may also prepare reports to appropriate agencies.
Note: If a class 3b or 4 laser system is to be operated on any of the premises under the control of Idaho State University, regardless of the means by which the laser system was obtained, the planned use of that system must be approved in writing by the LSO in consultation with the LSC prior to it being initially energized at Idaho State University. This responsibility falls directly on the employees associated with organizing the activity in which the laser system is to be employed.
APPENDIX 1. LASER CLASSIFICATION
CW LASERS
Lasers are classified from Class 1 through Class 4, with Class 4 having
the greatest hazard.
| Class | Power Output | Description |
| 1 | <0.4 microW | Considered safe for continuously viewing or are designed in such a way that prevents human access to laser. |
| 2 | 0.4 microW-1 mW | Visible light lasers will not cause eye injury if viewed momentarily. They can possibly present an eye hazard if viewed directly for a long period of time. |
| 3a | 1 mW-5 mW | Can not damage the eye within 0.25 second of the aversion response or blink reflex. Injury is possible if the beam is viewed with collecting optics or by staring at the direct beam. |
| 3b | 5 mW-500 mW | Present an eye and skin hazard from viewing the direct beam or a specularly reflected beam. No production of a hazardous diffuse reflection except when viewed with collecting optics. No fire hazard is presented. |
| 4 | >500 mW | These are the most hazardous lasers and may cause an eye and skin injury from the direct viewing, specular reflection, and diffuse reflection. These lasers can produce fire and generate hazardous airborne contaminants. |
APPENDIX 2. COMMON LASER TYPES AND WAVELENGTHS
Ultraviolet (0.180 micro-m – 0.400 micro-m):
| Laser type | Wavelength (micro-m) |
| Argon Fluoride | 0.193 |
| Krypton Fluoride | 0.248 |
| Neodymium:YAG (4th harmonic) | 0.266 |
| Argon | 0.275, 0.351, 0.363 |
| Xenon Chloride | 0.308 |
| Helium Cadmium | 0.325 |
| Nitrogen | 0.337 |
| Xenon Fluoride | 0.351 |
| Neodymium:YAG (3rd harmonic) | 0.355 |
Visible (0.400 micro-m – 0.700 micro-m):
| Laser type | Wavelength (micro-m) |
| Helium Cadmium | 0.442 |
| Rhodamine 6G | 0.450, 0.650 |
| Argon | 0.457, 0.476, 0.488, 0.514 |
| Copper vapor | 0.510, 0.578 |
| Krypton | 0.530 |
| Neodymium:YAG (2nd harmonic) | 0.532 |
| Helium Neon | 0.543, 0.632 |
| Indium Gallium Aluminum Phosphide | 0.670 |
| Ruby | 0.694 |
Near-infrared (0.700 micro-m – 1,400 micro-m):
| Laser type | Wavelength (micro-m) |
| Ti-Sapphire | 0.700 – 1.000 |
| Alexandrite | 0.720 – 0.800 |
| Gallium Aluminum Arsenide | 0.780, 0.850 |
| Gallium Arsenide | 0.905 |
| Neodymium:YAG | 1.064 |
| Helium Neon | 1.180, 1.152 |
| Indium Gallium Arsenic Phosphide | 1.310 |
Mid-infrared (1.400 micro-m – 3.000 micro-m):
| Laser type | Wavelength (micro-m) |
| Erbium:Glass | 1.540 |
| Homium | 2.100 |
| Hydrogen Fluoride | 2.600 – 3.000 |
| Erbium | 2.940 |
Far-infrared (3.000 ?m – 1 mm):
| Laser type | Wavelength (?m) |
| Helium Neon | 3.390 |
| Carbon Monoxide | 5.000 – 5.500 |
| Carbon Dioxide | 10.6 |
APPENDIX 3. FACILITY AND PERSONNEL APPLICATION
FOR CLASS 3b AND 4 LASERS
Contact TSO for documents found in Appendix 3.
APPENDIX 4. GUIDELINES FOR LASER OPERATING PROCEDURES
These guidelines are intended to assist lasers users in preparing standard operating procedures (SOPs) for laser facilities. The information should be used as a guide to allow you to develop SOPs specific to your laser systems.
Anyone writing operating procedures should be familiar with laser safety and the Idaho State University Laser Safety Policy. The Idaho State University Laser Safety Policy and ANSI Z136.1 require all SOPs for laser facilities to be approved by the LSO. It is recommended that the LSO be consulted early in the development of SOPs for guidance in determination of the specific laser hazards and required control measures.
For assistance in preparation of your facilities SOPs or laser safety concerns please contact the TSO at 282-2310/2311/3669 or email at gesell@physics.isu.edu.
I. INTRODUCTION
II. HAZARDS
Identify and analyze the specific hazards associated with this laser operation; include beam hazards as well as any non-beam hazards (electrical, hazardous chemicals, high pressure, plume emissions, etc.) and the accessible evacuation path from the NHZ in the event of an emergency.
III. HAZARD CONTROLS
Describe the means used to mitigate each of the hazards listed above in the HAZARDS section. Please refer to ANSI Z136.1, the Idaho State University Laser Safety Policy, or the LSO for assistance.
IV. TRAINING REQUIREMENTS
Describe the training requirements for the laser operator and incidental
personnel. The laser operator shall have formal training in laser
safety as well as hands on training with the specific laser system.
Incidental personnel shall be made aware of the specific hazards associated
with the laser operation.
V. OPERATING PROCEDURES
List the sequential events that describe the complete operation, including when to implement the hazard control measures. The procedures shall be written for the benefit of the laser operator who must read and understand them to perform the operation safely.
VI. ALIGNMENT PROCCEDURES
List the steps used to perform beam alignment on a laser or laser system. Special attention should be given to control measures that can reduce the potential for exposure. Examples for control measures are shutting down the main laser and using an alignment laser, reducing the power/energy of the laser, use of beam dumps for the primary beam, etc. All participants in areas where MPEs may be exceeded must use protective equipment.
Most laser accidents from the beam occur during the alignment operation.
VII. EMERGENCY PROCEDURES
Describe your planned actions in case of an accident, injury, fire, or other emergency. Include names and phone numbers of those that must be contacted in case of an emergency. The procedures shall include the TSO @ 282-2310/2311/3669 and ISU Public Safety @ 911 or 282-2515. Also post the emergency procedures in the laboratory.
VIII. RESPONSIBILITY AND REGISTRATION
State the name, title, and phone number (or office location) for the person(s) responsible for ensuring that the operation is carried out in accordance with the SOPs.
All laser systems must be registered with the TSO. Refer to Appendix
3 for information.
APPENDIX 5. EXECUTIVE MEMORANDUM
Contact TSO for a photocopy of the Executive
Memorandum
APPENDIX 6. Laser Safety Committee Member List
| Name | Department/College | Phone | |
| Doug Wells | Physics | 282-3986 | wells@physics.isu.edu |
| Kathy Blomquist | College of Technology | 282-3224 | blomkath@isu.edu |
| Rene Rodriguez | Chemistry | 282-2613 | rodrrene@isu.edu |
| Rich Brey | Health Physics | 282-2667 | brey@physics.isu.edu |
| Tom Gesell | Technical Safety Office | 282-3669 | gesell@physics.isu.edu |