TechTALK

Safety Cabinet Venting

Justrite like NFPA 30, does not recommend venting of Safety Cabinets and advices customers to leave vents plugged unless venting is required. Justrite, supplies each Safety Cabinet with the 2" NPT vent bungs. Vent bungs are for our customer’s convenience, when the EPA, or other laws mandate venting. The NFPA 30 advises, "if you must vent to vent to the outside in a manner that does not compromise the safety performance of the Safety Cabinet". This is a statement, with a lot of implication.

For Flammables:

Our vent bungs accommodates a 2"NPT threaded rigid steel pipe. Any blowers should be specified as safe for handling flammable fumes (explosion proof) and should be installed to evacuate fumes from the cabinet using negative pressure (suction) to avoid dispersing fumes into the room itself. It is important that any blower used shut down in the event of a fire to avoid drawing hot air and flame into the cabinet. Shut off dampers may also be required. Since flammable vapors are mostly heavier than air it is important to draw from the bottom bung and provide fresh air from the top bung. Justrite recommends that our customers retain a professional engineer to design a vent system and follow the guidelines listed here. Also, it is important that they consult the local building codes, fire code, and the authority having jurisdiction to understand the laws and to look for recommendations/interpretations prior to making the investment.

For Acids/Corrosiveness:

The vent pipe material specified should specified as compatible with the chemical being stored and will need to accommodate a 2" NPT connection. The same for any blower required. The blower should be installed to evacuate fumes from the cabinet using negative pressure (suction) to avoid dispersing fumes into the room itself. It is important that any blower used shut down in the event of a fire to avoid drawing hot air and flame into the cabinet. Shut off dampers may also be required. Justrite recommends that our customers retain a professional engineer to design a vent system and follow the guidelines listed here. Also, it is important that they consult the local building codes, fire code, and the authority having jurisdiction to understand the laws and to look for recommendations/interpretations prior to making the investment.

Justrite otherwise does not offer product solutions or advice for the venting of Safety Cabinets.

Note: It is strongly advised that the user seek professional engineering advice as every venting situation and facility is unique, as well as applicable building and fire codes. Designing and installing a safe venting system should be done by professionals who understand all requirements.


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