UL Certifies/Lists energy storage systems for use in accordance with new Article 706 in the 2017 NEC.  UL Certifies/Lists these systems under the product category Energy Storage Systems and Equipment (FTBW). 

The most effective protection is probably fire barriers and water spray for cooling and keeping the oil within the transformer tank, away from oxygen and below the flashpoint temperature.

The transformer is one of the most basic of electrical equipment found in a power distribution system, and just when you thought that a hunk of iron wound with wire couldn’t possibly be transformed, the industry does something that blows your mind. 

Where to find the ultimate expertise for determination of a hazardous location described in Section 18?