In addition to engineering and administrative controls, personal protective equipment for skin and/or eyes is often necessary when working with Class 3B or Class 4 laser systems. By OSHA regulation, all laser users required to wear personal protective equipment must undergo a hazard assessment for PPE use and must receive specific PPE training. Forms for completing each are included as Appendix 3 to this manual. Completion of these two items for each laser user is the responsibility of each department.
Eye protection suitable to the laser must be provided and worn within the laser control area if there is a potential for exceeding the MPE limit. Protective eyewear may include goggles, face shields, equipment filters, or prescription eyewear using special filter materials or reflective coatings. Exceptions may be approved by the LSO if the eyewear produces a greater hazard than when the eye protection is not worn.
No single type of eyewear will provide protection against all wavelengths of laser radiation; therefore, eye protection should:
- Provide enough visibility to perform the procedure.
- Be able to withstand the maximum power of laser radiation likely to be encountered.
- Be able to absorb the specific wavelength of radiation that is being used.
- Be clearly labeled with wavelength they are designed for, the optical density at that wavelength, together with the maximum power rating.
- Be inspected periodically by the laser operator to ensure that pitting, cracking and other damage will not endanger the wearer.
Lasers that can be tuned through a range of wavelengths present special problems. Broad band laser goggles may provide the level of protection required but they must be chosen with great care. If there is any doubt regarding the suitability of a particular type of eye protection, contact the Laser Safety Officer at 335-8501 for guidance.
Skin injuries from lasers primarily fall into two categories: thermal injury (burns) from acute exposure to high power laser beams and photo-chemically induced injury from chronic exposure to scattered ultraviolet laser radiation.
- Can result from direct exposure to the direct beam or specular reflections
- Injuries can be painful but are usually not serious
- Easily prevented through proper beam management and hazard awareness
- May result from chronic UV exposure to direct beam or specular and diffuse reflections.
- Effect can be minor to severe sunburn, increased risk of skin cancer.
- Protective clothing can help control UV skin exposure.
- Clothing that covers skin may be required to protect the skin for certain laser wavelengths and intensities
- High powered pulsed UV lasers are especially hazardous
- Window drapes should be used to prevent skin exposure to persons outside of the procedure room.