RESUMO
A passive diffusion dosimeter has been suggested as an economical and accurate means of sampling airborne concentrations of gases and vapors in the working environment. The dosimeter utilizes molecular diffusion through a tube of known geometry to obtain a quantitative determination of airborne concentrations of the contaminant of interest. A passive sampling dosimeter was designed to measure concentrations of aniline vapor in air. Diffusion tubes of 1.5, 3.0, and 4.5 cm lengths were tested under controlled conditions of relative humidity, air temperature, and vapor concentrations. The results indicate that the use of a passive diffusion dosimeter for determining time-weighted average concentrations of aniline is feasible. It was shown that a 1 cm diameter 3.0 cm length diffusion tube gave the most consistent results. It is suggested that further investigations be conducted in the development of passive diffusion dosimeters for other gaseous contaminants.
Assuntos
Poluentes Ocupacionais do Ar/análise , Poluentes Atmosféricos/análise , Compostos de Anilina/análise , Câmaras de Exposição Atmosférica/instrumentação , Difusão , Exposição Ambiental , Saúde Ambiental , Humanos , SegurançaRESUMO
Electron Spectroscopy for Chemical Analysis (ESCA) was explored as a means of studying the oxidation state of chromium in SMAC (coated electrode) stainless steel welding fume collected on Nucleopore filters in the laboratory. Chromuim VI and III (as a percent of the total chromium) obtained from ESCA analysis was applied to results from Neutron Activation Analysis (NAA) to yield an average of 69 microgram chromium VI per sample. Diphenylcarbazide/atomic absorption (DPC/AA) results are reported for samples submitted to an industrial laboratory. Possible chemical species and solubility of chromium VI in stainless steel fumes is discussed in light of analogy between the SMAC process and the manufacturing process for chromates.