Verify that the water temperature of your eyewash and shower is suitable
Did you know eyewash and shower water must be at a certain temperature? As a Field Safety Manager, I’d often find the issue of eyewash and shower water temperature confusing for my workers. While OSHA doesn’t specify a water temperature for eyewash stations or emergency showers, they did address the issue in an April 18, 2002, Letter of Interpretation.
It states, “It is the employer’s responsibility to assess the particular conditions related to the eyewash/shower unit, such as water temperature, to ensure that the eyewash/shower unit provides suitable protection against caustic chemicals/materials to which employees may be exposed.”
OSHA also notes that too hot or cold water can prevent a person from flushing their eyes for the 15 minutes recommended in emergencies or outlined on most safety data sheets (SDSs). Ensuring the right water temperature and proper placement became essential to avoid potential hazards and meet safety standards.
Temperature
American National Standards Institute (ANSI) Z358.1-2014 and some state-OSHA plans say that the flushing fluid used in emergency eyewashes and showers should be “tepid.” This is defined as a temperature range between 60 and 100 degrees Fahrenheit.
Temperatures of more than 100 degrees have proven to be harmful to the eyes and can enhance chemical interaction with the skin. Water less than 60 degrees can provide immediate cooling, but prolonged exposure can affect body temperature and delay or prematurely stop first aid treatment.
Mixing valves
Once activated, eyewashes must be used without requiring the use of the operator’s hands so that both hands can be used to hold the eyes open for flushing or the removal of clothing. This requirement would not be met if an employee was expected to fiddle with knobs to manually regulate the fluid flushing temperature of the eyewash or shower.
In these cases, a mixing valve in the faucet (for faucet-mounted units) or the corresponding plumbing (for plumbed units) may need to be installed. The ANSI standard does not require a mixing valve per se, but again, it does say that plumbed eyewashes must be able to deliver tepid flushing fluid.
Freeze protection
Sometimes, emergency eyewash and shower equipment must be made available under varying environmental conditions due to the nature of the work being performed. In some cases, freezing conditions can pose a problem. ANSI says that if there is a possibility of freezing, units must be protected to ensure that tepid flushing fluid is delivered.
For plumbed units, ANSI says there are several methods of freeze protection available, including:
- Electrical heat tracing designs – Units are wrapped with heat trace cable and insulation and then are jacketed with a protective shell.
- Frostproof hydrant designs – Supply lines are buried below the frost line, where they are resistant to freezing and deliver flushing fluid only when the unit is activated.
- Proximity designs – Outside units are located on a wall adjoining a heated space with the water supply and valves inside.
For self-contained eyewash units, ANSI says heated blankets that cover the entire unit may be used to keep the flushing fluid from freezing.
Key to Remember
ANSI and some state-OSHA plans say that the flushing fluid used in emergency eyewashes and showers should be “tepid.” This is defined as a temperature range between 60 and 100 degrees Fahrenheit.