Class IV clinical lasers and intense pulsed light
New Zealand currently has no legal requirements for medical laser use
All lasers and light based devices should be maintained with service programmes and have current and reliable technologies supplied by
reputable laser companies.
The principle hazard is unintended contact of eyes with the laser beam or intense light, either directly or indirectly through reflections.
The retina is particularly susceptible to injury from laser radiation in the visible and near infrared regions (400nm–1400nm). These wavelengths are readily transmitted through the ocular medium and are focussed on the retina. Permanent damage can occur instantly.
UVB and UVC and mid and far infrared are only absorbed by the conjunctiva and cornea whereas UVA can cause lenticular damage which might take years to develop. Iris colour can also be altered by the use of IPL within the orbital rim.
Other hazards include fire and explosions from laser beam contact with combustible and inflammable substances including surgical drapes and hair products as well as alcohol and acetone.
Airborne contaminants in smoke plumes (especially CO2 laser ablative procedures) have the potential for transmitting infectious agents, particularly hepatitis and papilloma viruses airborne contaminants.
Metal instruments can become heated and may reflect laser beams unless the metal is sintered. Particular care must be taken with endoscopic instruments.
Electrocution can rarely occur when fluids and high voltage systems coincide. The clinic must have a body protected electricity supply.
Interlocks such as door switches can prevent a laser firing if a door is inadvertently opened; alternatively door locks can be activated when a laser is operating. Other interlocks can be applied to covers and fibre connections.
Key operated master switch. Keys should be removed when laser is not operating.
Eye protection: Protective eyewear is essential and must have appropriate attenuation for the wavelengths in use. Side view protection and a good fit are essential. Labelling must show the optical density (OD) and wavelength band.
Smoke evacuation: Adequate extractive equipment with HEPA filtration and suitable treatment room ventilation.
Signs: ‘Starburst’ symbol on all laser room doors.
Laser Safety Standards
- AS/NZS 4173: 2004 Guide to the safe use of lasers in healthcare.
- AS/NZS 2211.1: 2004 Optical density grade and wavelength must be marked on protective eyewear. Eye examinations should also be undertaken. Laser safety officer (LS6) is appointed.
In this practice Registered Nurses have ‘in house’ and ‘independent’ training in non-ablative laser theory and treatments and in other light based devices such as intense pulsed light (IPL) and photodynamic therapy (PDT). Full time physician supervision and expertise is also on site.
- familiarisation with system operating procedures
- proper use of hazard controls, signage etc.
- the need for personal protection
- accident reporting procedures
- bio effects of laser on eye and skin