Performance evaluation under intoxicating atmospheres.

A new behavioral model has been developed and used to assess the performance of mice during exposure to carbon monoxide, hydrogen chloride, or subambient levels of oxygen. The apparatus is a ventilated 150-ft series of glass tubes forming an S-shaped exposure system. Performance evaluation was obtained for two sublethal responses: distance traveled/time and incapacitation. Performance of normal mice (Type I) or mice previously fitted with a tracheal cannula (Type II) was very reproducible and similar. Concentration-response relationships were obtained showing the deterioration of performance with exposures to CO from 2500 ppm, HCl from 1095 ppm, and below 8.8% ambient O2 level. This model is likely to be sensitive to other asphyxiants and irritants. It includes both distance traveled and time of performance prior to incapacitation. Both are critical parameters to be included in escape hazard analysis in fire situations and possibly in other accidents involving chemical spills.