Overview
- Manufactured
- Pyrophoric, toxic, corrosive gases
Another type of ventilated enclosure that you may encounter is a gas cabinet. As discussed in the gases portion of this training, a ventilated enclosure is required for cylinders of all gases that have NFPA health hazard ratings of 3 or 4, cylinders of gases that have a health hazard rating of 2 without physiological warning properties, and pyrophoric gases. Typically, if the cylinder is larger than a lecture size, then it will be located in a gas cabinet.
Gas cabinets have varying design features. The most basic cabinet has an access door that must be securely closed at all times. It will also have a small access panel that will allow an operator to get to the cabinet controls. It will be connected to the building ventilation system, typically hard-ducted. It will have an area where supply air enters the cabinet. Some cabinets will have sophisticated controls, sprinklers (which are required for reactive and flammable gases), alarms, etc. Some will have remote shut-downs, typically for pyrophoric gases.
Attempts to construct lab-made devices are not acceptable. Exhibit B shows a dryer vent placed over the cylinder valve which is not an acceptable substitute for a gas cabinet.