Comprehensive hygienic assessmentof the dust factor in the asbestos cement manufacturing industry
Objective: to conduct comprehensive hygienic studies of the dust factor in the asbestos cement manufacturing industry and to determine the presence of a relationship between the content level of respirable fibres and the mass concentration of suspended particles in order to actualize the methodology of the assessment of the air of a working area containing mineral fibrous aerosols. Materials and methods. The mass concentrations of dust and the content level of respirable fibres in the air of the working area and the morphological characteristics of dust aerosol were analyzed. Results. The content of dust in the air of the working area in terms of the mass measurements of suspended particles does not exceed the hygienic standards and ranges from 0.20 ± 0.004 mg/m3 to 1.47 ± 0.085 mg/m3, and the content level of respirable fibres is from 0.20 ± 0.044 f/cm3 to 1.13 ± 0.204 f/cm3. The presence of a positive correlation of moderate strength between the content level of respirable fibres and the mass concentration of suspended particles has been found. Conclusion. The microscopy of the preparations of dust samples makes it possible to determine a morphological picture which is characteristic for various stages of the technological process. There is a positive correlation of moderate strength between the content level of respirable fibres in the air of the working area and the concentration of suspended particles. However, the obtained patterns of dependence are capable of accounting up to 49.3 % of the variations of respirable fibres on the basis of the mass concentration of suspended particles, which does not make it possible to use them for the conversion of the values.