Occupational and recreational noise exposures at stock car racing circuits: An exploratory survey of three professional race tracks

Noise in stock car racing is accepted as a normal occurrence but the exposure levels associated with the sport have not been adequately characterized. Researchers from the National Institute for Occupational Safety and Health (NIOSH) conducted an exploratory assessment of noise exposures to drivers, racing team members, and spectators at three stock car racing events. Sound level measurements were conducted using sound level meters, personal noise dosimeters, and a digital audio tape recorder that made sound recordings for later laboratory analysis. Area sound level measurements were made during race preparation, practice, qualification, and competition. Personal dosimetry measurements were conducted on drivers, team members, and spectators. Findings showed time-weighted averages (TWA) that ranged from A-weighted 96 decibels (dBA) for a spectator in the stands during a race to 114 dBA for a driver inside a car during practice. Peak sound pressure levels exceeded the maximum allowable limit of 140 dB during race competitions. Personal exposure measurements exceeded the NIOSH recommended exposure limit of 85 dBA as an 8-hr TWA in less than a minute for one driver during practice, within several minutes for team members, and less than one hour for spectators during the race. Hearing protection use was variable and intermittent among team members and spectators. Among drivers and team members, there was greater concern for communication performance than for hearing protection.