FLIGHT CREW EXPOSURE TO OZONE CONCENTRATIONS AFFECTING THE VISUAL SYSTEM

To estimate the potential for ozone (0/sub 3/) effects on the human visual system in flight, 0/sub 3/ concentrations in Boeing 747-100 cockpits were measured during routine flights between London and the United States. From a review of previous reports, it appears that 0/sub 3/ may have both beneficial and harmful effects but that further studies of the visual system responses to 0/sub 3/ are needed before the present findings of 0.030 parts per million (ppm) mean 0/sub 3/ 0.200 ppm maximum 0/sub 3/, and 0.261 ppm-hours average cumulative 0/sub 3/ exposure can be effectively evaluated. Unexpectedly high 0/sub 3/ concentrations were encountered at altitudes below 18,000 feet and, at times, the 0/sub 3/ concentration was observed to decrease as flight level was increased. The clinical, operational, and policy implications of these findings are discussed.