RESUMEN
A new diffusion colorimetric air monitoring badge for sampling ethylene oxide is described. The Du Pont Pro-Tek C-70 badge has been laboratory validated over the range of 4-375 ppm-hours (0.5-47 ppm on an 8-hour TWA) using standard spectrophotometer readout in 1 centimeter (10 mm) cells. The lower range can be extended to 2 ppm-hours (0.25 ppm) by using 4 cm (40 mm) cells. The badge has an overall sampling and analytical method accuracy of +/- 13.5%. It meets NIOSH accuracy criteria and has a mean coefficient of variation CVT = 0.059. The badge has no temperature, pressure, relative humidity or face velocity effects over practical ranges. The response time is adequate to sample peak concentrations over short time periods. The badge may be used to determine ambient formaldehyde levels if suspected to be present along with ethylene oxide. Badges are shown to agree very well with the industry accepted and proposed ASTM pump/charcoal tube method in three extensive plant field tests. Badges were more precise than the charcoal tube/pump method in all field tests conducted.
Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Óxido de Etileno/análisis , Cloruros , Difusión , Exposición a Riesgos Ambientales , Compuestos Férricos , Humedad , Espectrofotometría Ultravioleta/métodos , Temperatura , Factores de TiempoRESUMEN
Results of three extensive plant field tests using both area and personal sampling and involving 51 sets of comparison samples show the Du Pont Pro-Tek Formaldehyde Badge to have excellent correlation with three commonly used formaldehyde monitoring methods. In addition, comprehensive laboratory validation tests are reported which confirm an overall accuracy of +/- 9.6 to +/- 11.6% for the badge over an exposure range of 0.12-6.8 ppm. Laboratory test data are also included showing that the badge: (1) meets NIOSH and OSHA accuracy requirements of less than or equal to +/- 25% down to 1.6 ppm-hours (200 ppb) for an 8-hour TWA exposure; (2) is capable of accurately sampling for 15-minute exposures; and (3) is not affected by pressure or relative humidity variations.