title: A routine for the control of the performance of microscopists evaluating airborne asbestos fibre samples on membrane filters by phase contrast microscopy.
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001194:Asbestos / Q000032:analysis*; D005374:Filtration / Q000295:instrumentation; D008858:Microscopy, Phase-Contrast; D013997:Time Factors
chemical_list: D000393:Air Pollutants; D001194:Asbestos