Workers' interpretation of self-assessment of exposure

The aim was to investigate how workers interpret and act upon results from self-assessment of exposure (SAE).

Workers in four sawmills in Sweden were supplied with diffusive samplers for measurement of terpenes. Workers received both oral and written instructions about terpenes, their medical effects and how to handle the samplers. Responsibility for sampling was left to the individual worker; written feedback about terpene levels was provided after each measurement. The number of measurements was registered. The workers and supervisors were interviewed about their attitudes, perceived control of their work environment, need for preventive actions and future surveillance of the workplace.

In total, 28 workers performed 100 terpene measurements. At one sawmill, there was a significant association between exposure levels and the number of measurements performed by each worker (rho = 0.79, P = 0.03). Contrary to instructions, supervisors played an important role in spontaneous organization of the measurements at each mill. Four measurements revealed terpene concentrations that exceeded the occupational exposure limits, and one preventive action was taken as a consequence of high levels. Seventy percent of the workers could not identify any reason for more measurements. Only 15% considered the measurements as their 'own' project, and the rest stated that they participated in order to satisfy the researchers.

Previous studies have shown that workers can perform valid measurements, both select a day and technically perform measurements. This study indicates that this ability is not sufficient to ensure that measurements will be done or that implementing measurements will result in preventive actions. Workers need additional support to take preventive actions and use SAE for ongoing surveillance.