Comparison of alternate methods of preparing wood sports floors for recoating

Recreational wood sports surfaces receive periodic refinishing. Most school sports floors are recoated annually. The two primary methods of preparing wooden sports floors (creating a "bondable" surface for recoating), "dry abrasion" and "wet abrasion," were examined for employee dust exposure. Refinishing workers' personal total dust exposures were measured for a large collegiate basketball court, a community center gymnasium, and two racquetball courts as well as areas immediately adjoining the work areas. The refinishing workers breathing zone total dust concentrations ranged from 7.2 to 39.0 mg/m(3) and for adjacent areas were 1.1 to 5.3 mg/m(3) for the dry abrasion method. During wet abrasion there were no detectable particles (<0.5 mg/m(3)) in either the work areas or the immediately adjoining areas. The authors conclude the wet abrasion method can control dust levels adequately to prevent cross-contamination of adjacent areas while preventing worker exposures. Further studies in this area would be of interest, particularly determining the nature of the dust and whether it contains any wood component, because certain hardwood dusts have been listed as confirmed human carcinogens.