Help!!!!

[tsalta]

Hi Folks

I need to answer a question for a job interview tomorrow and was lucky enough to get the questions before hand but I am not sure on one.

" What is the difference of Class A to Class B to Class C systems????"

I believe it is to do with DC systems but not fully sure! Is Class A for emergency lighting, etc

 

[Notsosmart]

Having read your new reply within your introduction post I beleive they may be referring to Lightning protection if so have a look here;

http://www.westcentralrailway.com/zip/AT_38_2006/50.06.5086.pdf

Alternatively fire extinguishers?