Laser safety - medical, dental and cosmetic applications

Reflective surfaces in the treatment room

The vast majority of medical and cosmetic lasers are 'Class 4', meaning that even reflections from rough/matte surfaces are potentially hazardous. We therefore often treat every surface in the room as if it were a mirrored surface and control exposure to the beam through the following administrative procedures;

Wearing of eye protection (everyone in the room),
Beam is always directed towards (or inside) the patient,
Make use of equipment features such as 'stand by' mode,
Interlocked/shielded fibres and shrouded footswitches.

We would generally recommend the "removal of any reflective surface which may further concentrate the intensity of the beam or increase it's Nominal Ocular Hazard Distance (NOHD)". In practice, reflective objects of this design are relatively uncommon.

Perhaps understandably, the above statement is often misinterpreted and quoted as simply "reflective surfaces". However, this alters the meaning of the intended recommendation and is inconsistent with the philosophy of treating every surface in the room as a potential hazard. In fact it could even lead people to think that the beam is only dangerous if pointed at a mirror.