Health Hazard Evaluation Report HETA 84-493-1593, General Services Administration, Washington, D.C.

摘要

An investigation of siren noise in ambulances (SIC-4119) was conducted in October, 1984. The evaluation was requested by the General Services Administration, Washington, DC, to quantify noise levels relative to siren speaker location before completing a proposed revision of the federal specification for ambulances. The effect of siren speaker location on sound pressure levels within type 1 ambulances was measured. Projected siren noise 10 and 100 feet from the vehicle was also measured. When siren speakers were placed on the roof of the ambulance driver cab, siren noise exposures within the ambulance averaged 109 A-weighted decibels (dBA) for the driver and 91dBA for the patient. The OSHA time weighted average noise standard is 90dBA. Overall noise was reduced when siren speakers were located in the grille area of the ambulance, the driver's and patient's exposure being 87 and 76dBA, respectively. Siren noise levels were 122 and 98 to 105dBA 10 and 100 feet outside the ambulance, respectively. The authors conclude that a potential hazard due to ambulance siren noise exists. Recommendations include relocating siren speakers in the grille or bumper area, keeping the driver cab windows closed when the siren is on, and using the siren only when necessary.