Emergency showers, eyewashes and drench units are common equipment in hospitals, laboratories, science classrooms, maintenance shops and anywhere hazardous chemicals are handled. OSHA regulations require “Where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing of the eyes and body shall be provided within the work area for immediate emergency use.” (OSHA 29, 1910.151(c))
When an emergency fixture is installed, it must be installed per the standard ANSI Z358.1 – American National Standard for Emergency Eyewash and Shower Equipment. This standard mandates the requirements for fixture locations, flow rate, duration and temperature of the water supply.
Emergency fixtures must be able to be reached from the hazard location in less than 10 seconds. The average person can travel approximately 55 feet in 10 seconds. Obstructions and the compromised state of a contaminated person should also be considered when placing the fixtures.
The minimum flow rate for emergency eye/face wash is 3.0 gallons per minute at 30 psi. The minimum flow rate for an emergency shower is 20 gallons per minute at 30 psi.
A full 15 minute flush is recommended for adequate rinsing of the contaminant from the eyes or body. The water supply and water heating system must be designed to meet this duration.
Tepid water must be provided for the flushing fluid. Tepid water is defined as water with a temperature range of 60-100 degree F. In most facilities this requires a thermostatic mixing valve to blend domestic cold water and hot water to meet the tepid water requirement.
In addition to design considerations, it is also critical that emergency equipment be tested regularly to insure that it will function properly when it is needed.