we have customer that stores flammable liquids some of the materials are stored in doors. They also have an area where they mix batches of products in totes with flammable liquids and nothing I asked them if the area was a Classified Area and they couldnt tell me yes or no. I was wondering who decided if area is to be designated a hazardous classification. I am not sure how to proceed. Im kinda worried about doing electrical in that area without proper instruction. I do know that if I mix Aluminum with Ammonium Phosphate that it will start a fire in that area.