NFPA 497 Classsification for Labratory Operation?

[StoneCold]

Hi guys.I have a project in a labratory and I need to make an electrical area classification drawing. The project is a 10 gallon chemical reactor inside a walk in labratory hood. The hood has forced ventilation and I am getting reading on the face velocity today. The real issue is by NFPA 497 the area would be classified as Class 1 Div 1 Group C+D within 5ft of any frequent connection point or vent, and Class 1 Div 2 Group C+D within 15 ft of the vent/connection. But how does this play out with the reactor being in a hood? My real issues are electrical equipment outside of the hood. If it matters the hood is 8ft wide, 4ft deep and 8ft.high. Is NFPA 497 The right code to apply here? Is there a better labratory code. Most of the lab equipment in the area is general duty electrical so I don't know how this should play out.

Thanks for any help you can give.

Regards
StoneCold

 

[stookeyfpe]

Stone

Where are your connections for the container and what's the vapor density of the liquid? Is the liquid under pressure or a liquefied compressed gas? What is the operating temperature of the system? What's the liquid in the reactor (an assumption on my part)?

In my world, if the vapor density is > 1 and the system is not pressurized, you may be able to reduce the hazardous (classified) location boundary.

Based on your description, the entire hood could be Division 1 or Division 2, depending on the material. We need more data

We talked about a year ago on your fire flow problems. I understand you're dealing with some sexy but energetic and funky materials. In some previous messages I offered you my phone number. Call me if you want to avoid writing a book report.