Environmental Evaluation of Stress and Hypertension in Municipal Bus Drivers

摘要

A survey of carbon-monoxide (630080), lead (7439921), and noise exposures among municipal bus drivers (SIC-4131) was conducted. The survey was part of a multidisciplinary study of stress and hypertension among transit operators. Personal carbon-monoxide, lead, and noise exposures of the drivers were measured on their runs in the San Francisco, California area. Sampling was performed on electrical and diesel coaches during morning and afternoon hours and during summer and winter months. One driver was monitored for both noise and heart rate. Time weighted average (TWA) carbon-monoxide concentrations ranged from 1 to 23 parts per million. TWA lead exposures ranged from 0.15 to 3.67 micrograms per cubic meter. Carbon-monoxide exposures were not correlated with type of coach, time of day, or season. Highest TWA lead exposures occurred in diesel coaches during the mornings. TWA noise exposures ranged from 65.3 to 79.0 A-weighted decibels. The highest TWA noise exposures occurred on diesel coaches in the afternoons. All exposures were below the relevant standards. There was no apparent correlation between heart rate and noise exposure. The authors conclude that bus drivers are not overexposed to carbon-monoxide, lead, and noise. The relationship between these factors and stress has not been elucidated.