Transformers oil containment pit

[Kmohandes]

I am designing foundation/oil pit and firewall for a few large transformers. However I'm having difficulties regarding the oil pit requirements. does anybody know about any code/standards which clarify the oil containment requirements for transformers?
Thanks,

 

[bimr]

Here is a link to a guide that explains the general requirments:

http://www.epa.gov/region6/6sf/sfsites/oil/elecutil.htm

 

[Kmohandes]

Thank you very much.
I am doing these designs for Canada. Do you know any guideline which is for Canada?

 

[bimr]

The Canada Oil and Gas Operations Act promotes safety, environmental protection, conservation of oil and gas resources, and joint production arrangements. The act is jointly administered by the Department of Natural Resources and Indian Affairs and Northern Development Canada. The following sections are pertinent:

Section 25 prohibits a person from causing or permitting a spill and establishes a duty to report any spills that do occur. Reasonable measures must also be taken to respond to the spill and protect the environment. Section 25 also enables anyone other than the spiller to recover costs associated with responding to the spill.

http://lois-laws.justice.gc.ca/eng/acts/O-7/index.html

 

[dik]

Oil containment is a requirement in the US under the NEC, but it is not a requirement under the current Canadian electrical code. You should check for requirements under the various provincial environmental laws. IEEE 980 also have some information. We have found it is generally driven by insurance requirements more than anything.

For the last few projects, I've designed the containment for 110% of the oil volume and a 24 hour storm event. We've also used a product supplied by Albarrie (sp?) called Sorweb. This is a material that allows drainage of water, but forms an impervious gel when subjected to transformer oil. Containment pits are filled with a 'firestone' (limestone aggregate) which has a large void ratio.

Fire separation between transformers has used a 2 hour metal clad barrier, filled with mineral wool insulation. Roxul has a tested assembly.

Dik

 

[bimr]

Oil containment may be required by the particular electrical code to prevent the spread of fire (ie. to a building).

Oil containment may be required by an environmental code to prevent the spread of oil into the environment.

These issues will depend on the size and location of the transformers (which have not been identified). The electrical code is also typically adopted by the municipality where the project will be located.

As these isues may change on a case-by-case basis with each project, you probably should talk to the local AHJ for specific details related to your project.