Injury from the decompression component of an air-blast wave.

Abstract

PREVIOUS experiments have shown that about 80 per cent mortality is to be expected when 60-day old mice are explosively decompressed, in a matter of 30 m.sec., from a pressure of 80 lb. per sq. in. above atmospheric. Since the positive phase of an air blast wave is characterized by a shock front followed by a rapid drop in pressure comparable to explosive decompression, it was thought of interest to investigate the lethal effect of this component of the blast wave. Accordingly, mice were subjected to 80 lb. per sq. in. over-pressure for varying durations of time and then explosively decompressed. No lethal effect was observed until the mice had been under pressure for times longer than 100 m.sec. At 1 second the mortality had only risen to about 12 per cent, as compared with the control data on 80 per cent mortality which was obtained when the mice were under pressure for a matter of 1 min. It is therefore concluded that the explosive decompression component of the blast wave has no lethal effect per se. Details of this work will be reported later.