What is the difference between a stay-open and self-closing valve?
The ANSI Z358.1 standard for showers and eyewashes recommends that the activating devices for showers and eyewashes remain open once they are activated. To achieve this Speakman Company uses ball valves which require specific actions to open and close the valve permitting the eyewash or shower to be used hands free after activation. A self closing valve is a spring activated device that requires a specific action to activate but will close on its own. This type of device requires the user to hold an activating lever while the unit is in operation and does afford hands free operation as required by the ANSI standard. In some school applications self-closing valves are permissible provided that approval is received from the local code authorities. In these situations this is desirable to prevent accidental or mischievous activation of a shower which could cause significant water damage.
