Quantifying synthetic vitreous fiber surface contamination in office buildings

A reliable method for determining the distribution of synthetic vitreous fiber (SVF) densities found on building surfaces is presented with data collected from rooms in 40 office buildings in the United States. The initial survey of 20 buildings-complete with collection, counting, and analysis of SVF loading-found that nearly 60% of the samples had zero or one fiber counted. To resolve the nondetects, especially for lighter dust loading, the counting technique was modified. The detection limit improved as the zero fiber count decreased from about 43% in the initial survey to about 14% of the samples taken from 20 additional buildings. Analysis of the results indicated that the variability within rooms was much larger than the variability between rooms or between buildings. This variability is attributable to differences among the contact surfaces. Surfaces seldom contacted had greater SVF loading than those in frequent or constant contact. The technique developed will standardize evaluation of SVFs in building dust and can be used to assess potential causes of cutaneous and mucous membrane irritation symptoms in future studies.