ULC S601 Tank for Indoor Location and Difference from API 650 1

[az5333]

HI. I am working on a project where we are evaluating if a ULC S601 designed diesel storage tank (supplying fuel oil to the diesel engine placed in the same room) is suitable for indoor installation or not? As per ULC S601, installation of such tanks shall be in accordance with National Fire Code of Canada, Part4 and CSA B139. NFC also refers back to CSA B139. I consulted CSA B139 and it says if a tank is constructed per S601, it is suitable for indoor installation. There are some additional checks regarding installation in B139 (distance from nearest fire equipment, temperature of the building, egress, gauge, venting etc.) that I am considering in addition to the construction per S106 standard, My question is:

1. Is my approach correct or am I missing something?
2. What is the difference in API650 tank design as compared to S601 design and why doesn't B139 state API 650 tank here?

Appreciate the insight and advise.

 

[JStephen]

API-650 is for flat-bottom vertical welded metallic tanks. Primarily aimed at large field-erected tanks, although it can be used for smaller shop-fabricated tanks...but still welded flat-bottom vertical tanks.

 

[az5333]

Thanks JStephen for the response. Okay got it. Does that also mean that API 650 tanks (storing combustible and flammable liquids) are only meant for outdoor installations only and if it has to be installed indoors, any tank with combustible / flammable liquids has to follow one of the specs given in CSA B139 (which does not include API 650)?

 

[JStephen]

API-650 tanks are not limited to outdoor use necessarily, but in the US, smaller tanks like that would be more likely some form of UL-142 tank rather than API-650.

 

[az5333]

Thanks JStephen for the explanation. Looks like UL-142 is the US equivalent for ULC-S601 standard.