Abstract. Some lasers produce a loud photo-acoustic effect when treating skin. Although safety issues with regard to eye and skin protection are well known, we were unable to find any literature relating to noise production. We therefore measured the sound levels produced by three Erbium-YAG lasers (Continuum Biomedical 1J and 2J, and Laserscope). Measurements were made at distances of 50 and 5cm, to represent levels reaching the laser-user and the patient, respectively, at a variety of energy (0.5, 1, 1.5 and 2J) and spot settings (2, 3.5, 5 and 7mm). Levels ranged from 72 to 99 decibels frequently exceeding safe limits, and increased with increasing energy setting, decreasing spot size and decreasing distance. We conclude that sound levels should be measured for lasers in medical use, so that where necessary both the patients and healthcare workers may avoid this potential hazard by wearing appropriate ear protection.