Isocyanate exposure in bathtub refinishing: à propos a case of occupational asthma.

Work-related asthma in a bathtub refinishing technician prompted measurements of isocyanate exposure in this operation. Very high levels of hexamethylene diisocyanate (HDI) oligomer, up to 8500 microg/m3 NCO, were found during top varnish spray-painting, whereas the levels of HDI monomer were substantially lower. The results suggest that only full-piece, self-contained respirators would suffice to protect technicians from serious pulmonary disease.