What type and size of fire Extinguisher is Required by a propane tank

For flammable liquid storage areas located outside, a portable fire extinguisher with a rating of not less than 20-B units should be located not less than 25 feet, nor more than 75 feet, from the storage area [1]. For bulk plants, provide at least one approved portable fire extinguisher with a minimum rating of 12-B, C [2]. For storage locations other than supply depots, ensure at least one approved portable fire extinguisher with a minimum rating of 8-B, C is available 10, 13.