Data were obtained from the exposure of eleven men to dichloromethane concentrations of 50, 100,250, and 500 ppm, 1,3 or 7.5 hours per day; for up to five successive days and from the exposure of nine women to 250 ppm on a similar schedule. Breath concentrations of the solvent following exposure were related mathematically to exposure parameters as were blood concentrations of the metabolite, carbon monoxide(as carboxyhemoglobin percentage saturation elevations). The resulting emprical equations can be used to predict the consequences of many industrial and non-industrial exposure situations.