Class 1 Div 1 Distance to Nonhazerdous

[cesmllooper]

I would like to install equipment away from the hazerdous zone. Could someone tell me where in the code book if any is the distance away from class 1 div 1 location where it is considered nonhazerdous? This is an outside Tank Farm.

 

[rbalex]

I would like to install equipment away from the hazerdous zone. Could someone tell me where in the code book if any is the distance away from class 1 div 1 location where it is considered nonhazerdous? This is an outside Tank Farm.

Your question is a bit too general - so for now I can only give a general answer.

Article 515 will be your Staring point. You have to establish what equipment or process creates the hazardous location in the first place. After that, then the "geometery" of the location will begin to influence the various zones. In your case, the type of tank construction and containment methods for leaks and spills.

The measurements are usually taken from the equipment or specific devices on the equipment creating the Class I location (tanks, relief valves, etc.) but containment will also affect it.

You have said it is outside, so there will also be a Division 2 area - possibly outside the containment.

In ALL cases documenting the electrical area classification is an NEC requirement [Section 500.4(A)]

Depending on the size of the equipment and nature of your facility, you may also want to consult NFPA 30, NFPA 497, or API RP500.

 

[Rockyd]

500.5

Third sentence states -

Each room, section, or area shall be considered individually in determining location.

I would listen to Bob. Lots of ground to be covered in classified spaces!

 

[nakulak]

in any classified area we have worked on, some governing body or engineer on record has determined the classified zones. Because of the liability involved, the potential for catastrophic failure, and the lack of expertise on our part, we would never attempt to assume the responsibility for determining a classified boundary.

 

[CWillcox]

NFPA Code Referance

NFPA Code Referance

Part of the documents that I use to determine area classification is NFPA 497 & 499. But as the other folks have pointed out, no simple solution can be provided without a detailed engineering review.

 

[petersonra]

I would like to install equipment away from the hazerdous zone. Could someone tell me where in the code book if any is the distance away from class 1 div 1 location where it is considered nonhazerdous? This is an outside Tank Farm.

Somewhere there is likely a document that defines the extent of classified areas for this installation. I would be relying on that document.

One such document I saw showed a plot plan with all fenced in areas noted as being division 2 unless shown as div 1, and all areas outside the fenced in area being non-classified. Areas that were division 1 were hatched in.