Laser Safety Program: Laser Hazard Classifications (2024)

FAQs

Laser Safety Program: Laser Hazard Classifications? ›

For visible-beam consumer lasers, there are four main classes. Each is described in more detail here: Class 2, Class 3R, Class 3B and Class 4. The first two Classes are relatively safe for eye exposure; the last two are hazardous. The chart below shows how the eye injury hazard increases as the laser's power increases.

For visible-beam consumer lasers, there are four main classes. Each is described in more detail here: Class 2, Class 3R, Class 3B and Class 4. The first two Classes are relatively safe for eye exposure; the last two are hazardous. The chart below shows how the eye injury hazard increases as the laser's power increases.

The classifications are as follows: Class 1. This class is eye-safe under all operating conditions. A Class 1 laser is safe for use under all reasonably anticipated conditions of use; in other words, it is not expected that the MPE can be exceeded. Class 1 Product.

There are four classes of lasers (Class III lasers have two subclasses). Class III and Class IV lasers are the most hazardous. The recognized industry standard for the safe use of lasers, American National Standard for Laser Safety [ANSI Z136.

Class 4 lasers and laser systems operate at greater than 500 mW (continuous), can emit any wavelength, and are considered an eye, skin, fire, and diffuse reflection hazard. The most stringent control measures have been established for these lasers.

These classifications are Class 1, Class 1M, Class 2, Class 2M, Class 3R, Class 3B, and Class 4, with Class 1 lasers being exempt from any kind of control due to their lack of hazard and Class 4 lasers requiring strict controls in order to reduce the risk of exposure to the eyes or skin.

Class 3 lasers have between 1 and 500 mW. This group is referred to as therapeutic 'cold' lasers and come with 'eye caution to eye danger'. Class 4 lasers have more than 500 mW and are referred to as 'hot' lasers.

Class 2 lasers are low power (< 1mW), visible light lasers that could possibly cause damage to a person's eyes.

Class 3B visible-light lasers are hazardous for eye exposure. They can cause burns to the retina. A person cannot turn away or blink fast enough to prevent retinal eye injury from a nearby Class 3B laser. At the low end, around 5 to 50 milliwatts, a Class 3B laser poses a moderate risk of eye injury.

Class 5 Photonics offers ultrafast, high power laser systems and EUV sources for demanding applications from bio-imaging to ultrafast science and attosecond science.

What are the safety hazards of lasers? ›

Risk of injury increases when viewed with optical aids. Immediate skin hazard from direct beam and immediate eye hazard when viewed directly. Immediate skin hazard and eye hazard from exposure to either the direct or reflected beam; may also present a fire hazard. Non-Ionizing Radiation: Standards and Regulations.

Classification is determined by calculations based on exposure time, laser wavelength and average power for CW or repetitively-pulsed lasers and total energy per pulse for pulsed lasers.

Health hazards include chemical hazards (solvents, adhesives, paints, toxic dusts, etc.), physical hazards (noise, radiation, heat, etc.), biological hazards (infectious diseases), and ergonomic risk factors (heavy lifting, repetitive motions, vibration).

Class I. Inherently safe; no possibility of eye damage. This can be either because of a low output power (in which case eye damage is impossible even after hours of exposure), or due to an enclosure preventing user access to the laser beam during normal operation, such as in CD players or laser printers.

There are four main classes for visible-beam lasers: Class 2, Class 3R, Class 3B and Class 4. The first two are relatively safe for eye exposure; the last two are hazardous. The chart below shows that the eye injury hazard increases as the laser's power increases.

Class 4 is the highest class in terms of laser hazards. If you're within the hazard zone, you're exposed to severe eye and skin injuries. In addition, combustible materials shouldn't be in the laser's surroundings to avoid fire hazards. Diffuse reflections of class 4 lasers are also hazardous.

Class IV laser therapy is an effective treatment for a wide variety of pain and inflammatory injury conditions because the laser itself stimulates all types of cells, including those that make up muscles, ligaments, cartilage, nerves, and bone.

The Four-Level System. Consider a four level laser. system. Level 1 is the ground level and levels 2,3, and 4 are excited levels of the system. Atoms from the level 1 are excited by a pump to level 4, from which the atoms decay very rapidly through some nonradiative transition to level 3.

Laser Hazard Classes

The FDA recognizes four major hazard classes (I to IV) of lasers, including three subclasses (IIa, IIIa, and IIIb). The higher the class, the more powerful the laser is and the greater the potential to pose serious injury if used improperly.