We used two types of dosimeters. The preintervention measurements were taken with a Metrosonics model 7000 noise dosimeter. Quest Technologies acquired this company, and an equivalent model, the Q300, was used for postintervention measurements. It's a rectangular device with an attached microphone; it weighs 15.5 oz. and measures 5.5"x 2.8" x 1.4". Information on established reliability can be obtained by contacting the company (http://www.quest-technologies.com). We acquired the dosimeters we used through our institution's safety department; our use of them doesn't imply an endorsement. There are several manufacturers and various types of dosimeters available.