Rockwell Laser Industries keeps an up-to-date record of laser injuries, and an incident report form, on its web site at http://www.rli.com. The total of 395 reported incidents between 1964 and 1998 is relatively low, but we agree with Rockwell that this is only the 'tip of the iceberg'. But while the results say little about the absolute risk associated with laser use, an analysis in terms of type of laser used and context of injury is highly instructive.

Rockwell has classified the reported incidents into 14 significant cause, as listed below in order of decreasing probability. The items on this list are not altogether mutually exclusive, however. Nevertheless, the list does support the view that open beam alignment work, which incorporates the first three items in the list, is undoubtedly the most hazardous single laser activity.

Rockwell's top 14 reported causes of laser-related injuries

1. Unanticipated eye exposure during alignment.
2. Misaligned optics and upwardly directed beams.
3. Available laser eye protection was not used.
4. Equipment malfunction.
5. Improper method of handling high voltage.
6. Intentional exposure of unprotected persons.
7. Operators unfamiliar with laser equipment.
8. No protection provided for associated hazards.
9. Improper restoration of equipment following servicing.
10. Incorrect eyewear selection and/or eyewear failure.
11. Accidental eye/skin exposure during normal use.
12. Inhalation of laser-generated fume or viewing of secondary radiation (UV, blue light).
13. Laser ignition of fires.
14. Photochemical eye or skin exposure.

More detailed analysis of the data reveals that the Nd:YAG laser has been the laser responsible for the greatest number of reported incidents, accounting for 25% of the total to date. By comparison, the CO2 laser makes up only 12% of the total, despite the fact that it is a more common laser, and one that is often used in a more relaxed manner.

The overall split of incidents according to laser wavelength shows visible and near-infrared laser injuries accounting for more than 80% of all the reported incidents. It is undoubtedly true that the more significant the incident the more likely it is to get reported, an effect that may well be distorting the figures.

The main lesson from these statistics is to pay attention to alignment procedures. Visible lasers offer maximum temptation to remove eyewear, and we strongly recommend that LSOs ensure that effective beam visualisation hardware is made available (e.g. cameras, scintillation screens) to reduce the temptation for eyewear removal during open-beam Class 3B or 4 visible laser work.

Pro Laser can provide documented safe procedures for alignment and other open-beam activities.