Reliability of Measurement of Evapotated Benzene Homologue Concentrations with the Benzene-detection Tube

The authors made an investigation on the reliability of measurement with the benzene detection tube, which is widely used as a rutine in order to measure the amount of benzene and its homologus in the air of workshops. The results of the investigation were as follows. The richer the benzene concentration in the air, the larger the probable error of the mean of obtained values whereas the coefficient of vareation of obtained values at a minimum. The same results were obtained in cases of toluene and its mixture with benzene. In the estimation of the benzene-like mist in the workshop air evaporated from sprayed paint, values got with benzene-detecion tubes showed half the values obtained by the sulphuric acid-formalin method.