A vent limiting orifice or device when used with Maxitrol regulators, does not release or relieve fuel gas into the environment during normal operation.
Vent limiters are designed for use indoors and in spaces where limiting the amount of gas escapement due to diaphragm failure is critical. Vent limiters should not be used outdoors if they are exposed to the environment.
Vent limiters can only be installed in regulators for which they are certified. Vent limtiers must only be installed directly into the vent connection of the regulator without intermediate pipe or fittings. When using a vent limiting deivce, the regulator must be installed in a horizontial upright position.
NOTE: Maxitrol vent limiters meet ANSI Z21.80/CSA 6.66. The requirement states "Vent limiters shall be of materials having melting points of not less than 800øF (427øC)."