Introduction

LASER is an acronym for Light Amplification by the Stimulated Emission of Radiation. The ‘light’ produced by a laser is a form of non‐ionising optical radiation.

Lasers come in various shapes and forms. They have many uses in teaching, research, manufacturing, medicine, dentistry, communications, shop checkouts and most commonly at work in the office. In fact, some applications may be so well engineered that users are not even aware that the equipment contains a laser.

The principal legislation that applies to laser safety is the Control of Artificial Optical Radiation (AOR) Regulations 2010. The safety of laser pointers broadly fall under two pieces of legislation; the Air Navigation Order that is managed by the Department for Transport, and the General Product Safety Regulations (GPSR) for which BEIS is responsible.

Laser Beam Hazards

The health effects that could occur due to exposure to a laser beam are damage to the skin and eyes.

Skin effects include erythema, elastosis (photoageing), immediate pigment darkening (tanning), burns and skin cancer

Eye effects include photokeratitis, photoconjunctivitis, cataracts, photoretinal damage and burns

Laser Classification

A system of laser classification is used to indicate the potential risk of adverse health effects.

The laser classification scheme is taken from BS EN 60825-1.

Class 1: laser products that are considered to be safe during normal operation including long term direct intrabeam viewing even when using optical viewing instruments.

Class 1M: safe for the naked eye under reasonably foreseeable conditions of operation but may present a hazard if magnifying optical instruments are used with them.

Class 2: a person receiving an eye exposure will be protected from injury by their own natural aversion response. However, repeated deliberate exposure to the laser beam may not be safe.

Class 2M: similar to a Class 2 laser product, however, they can be harmful to the eye if the beam is viewed using magnifying optical instruments or for long periods of time.

Class 3R: direct intrabeam viewing is potentially hazardous but the risk of injury is relatively low for short and unintentional exposure.

Class 3B: hazardous to the eye if direct intrabeam exposure occurs. Viewing specular and diffuse reflections is also not normally safe but they are generally safe to the skin.

Class 4: High power lasers for which direct beam and reflected beam viewing is always hazardous. Diffusely reflected beams should also be assumed to be hazardous.

Laser Safety Management

When determining which type of laser is required for the task to be undertaken, the safest option should be chosen. Therefore, the lowest class of laser possible should be used and the lowest power output possible.

A risk assessment should always be produced prior to undertaking tasks using a laser, ensuring it considers all modes of operation such as alignment, set-up and maintenance as well as normal operation.

Departments that use lasers should appoint a Laser Safety Officer (LSO) who has specific duties to ensure that laser operations are safely managed.

The risk assessment and management arrangements should consider the following (list not exhaustive):

  • Totally enclosing the laser in an interlocked cabinet to prevent exposure to the beam

  • No windows or windows covered to avoid laser exposure outside the controlled area

  • Use of shutters, attenuating filters to prevent access to the laser beam from the aperture

  • Key switch which renders the laser inoperable when removed

  • Laser on indicator outside the laboratory door

  • Laser-lab door interlock system that shuts the laser beam off when entered

  • Use of alignment aids

  • Local rules including access restrictions, protection measures and contingency plans

  • Hazard warning signs and contact details on the laser area door

  • Correct Personal Protective Equipment for the type and class of laser being used

  • Specific procedures for set-up and alignment when the laser beam may be exposed

  • Appropriate information, instruction and training. Training records to be kept.

Laser Pointers

Laser pointers are commonly available and some can be classed higher than Class 1 and could cause harm. Therefore, they should be purchased with caution; they should be low power (<1mW) and no more than Class 2. Instructions for their safe use should be readily available.

They should only be purchased from reputable suppliers.

When operating laser pointers, users must ensure that they use them in a safe manner and do not expose themselves or others to the beam. Laser pointers are not to be modified in any way.

  • Follow the manufacturer's safety instructions
  • Take care when operating the laser pointer
  • Keep the ‘on’ button depressed only when necessary