Effect of Water Flow Rate on Decontamination Efficiency of Emergency Safety Showers

Abstract

Standards for overhead emergency safety showers used for decontamination in laboratories and production sites specify the spray pattern and the water flow rate. Up to now, there has not been a scientific basis for these requirements. The decontamination of water-soluble contaminants has been investigated using 15 customary shower heads at 20 to 110 L min-1 water flow rate. A general relationship between water flow rate and decontamination effectiveness could not be established: At a flow rate of 30 L min-1 the wash-off time in general did not exceed the time observed at considerably higher flow rates. The shortest decontamination time has been found with a spray pattern that does not fulfill current standards