Blast/Firewall 1

[jncza]

Hi.
The insurance company want us to built Blast/Firewalls between our gensets and transformers.Can anybody give me some advice regarding regulations or standards.

 

[Jebb]

If you're in the USA you can start with NFPA 850-00 (Fire Protection for Electric Generating Plants & HVDC Converter Stations). Also a good Fire Protection Engineer would know what your insurance co wants....

 

[rcw retired EE]

Factory Mutual has a good guide for installation of blast/fire walls that is very similar to NFPA 850. The insurance company may be able to get you a copy of the FM document.

Usually the most cost effective blast wall is a CMU (concrete block) wall located so any structure of concern (another transformer, generator or a building wall that does not have the required fire rating) is 50 feet line-of-sight away. The wall can be a straight line, "L" or "U" shaped, designed to cut off any line-of-sight between the transformer tank and the other objects, unless it is more than 50 feet.

If there is a building next to the transformer, the wall has to be tall enough to get the 50' line of sight looking over the top of the wall at the building.

Usually the wall is as high as the bushings or the conservator tank on top of the transformers. Exploding bushings can explode like grenades and damage adjacent bushings or equipment with shrapnel.