Dangers of Exposure: Uncovering Beam Hazards of Lasers
11 July 2019
Let’s talk about the beam hazards of lasers. The word “laser” is an acronym for Light Amplification by Stimulated Emission of Radiation. In fact, lasers produce an intense, highly directional beam of light. As a result, if directed, reflected, or focused upon an object, laser light will be partially absorbed, raising the temperature of the surface and/or the interior of the object. Therefore, the laser can potentially cause an alteration or deformation of the material.
The human body is vulnerable to the output of certain lasers. Under certain circumstances, exposure can result in damage to the eye and skin. Such as looking directly into a laser beam.
In addition to direct hazards to the eye and skin from the laser beam itself, it is also important to address other hazards associated with the use of lasers. These non-beam hazards, in some cases, can be life threatening. For example, electrocution, fire, and asphyxiation. Therefore, the employment of safety and/or industrial hygiene personnel may be necessary.
Below is a table of the classes of lasers and potential hazards.
Laser Hazard Classes (source: U.S. FDA Laser Hazard Classes)
| Class FDA | Class IEC | Laser Product Hazard | Product Example |
| I | 1, 1M | Considered non-hazardous. Hazard increases if viewed with optical aids, including magnifiers, binoculars, or telescopes. |
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| IIa, II | 2, 2M | Hazard increases when viewed directly for long periods of time. Hazard increases if viewed with optical aids. |
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| IIa, II | 2, 2M | Hazard increases when viewed directly for long periods of time. Hazard increases if viewed with optical aids. |
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| IIIa | 3R | Depending on power and beam area, can be momentarily hazardous when directly viewed or when staring directly at the beam with an unaided eye. Rrisk of injury increases when viewed with optical aids. |
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| IIIb | 3B | Immediate skin hazard from direct beam and immediate eye hazard when viewed directly. |
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| IV | 4 | Immediate skin hazard and eye hazard from exposure to either the direct or reflected beam; may also present a fire hazard. |
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Above all, ANSI Z136.1 specifies that any facility using Class 3b or Class 4 lasers or laser systems should designate a Laser Safety Officer. Most importantly, this person will oversee safety for all operational, maintenance, and servicing situations.
This person should have the authority and responsibility to monitor and enforce the control of laser hazards. In addition, this person is also responsible for the evaluation of laser hazards and the establishment of appropriate control measures.