Conn. Agencies Regs. § 29-349-336
Unless the storage of a greater quantity is approved by the State Fire Marshal, not more than 2,500 tons of bagged ammonium nitrate shall be stored in a building or structure not equipped with an automatic sprinkler system suitable for high hazard occupancies. When determining whether greater quantities shall be permitted without sprinkler protection, the State Fire Marshal shall take into consideration proximity of the storage building to built-up areas, possible presence of contaminates in the storage building, and the availability of water supplies. Sprinkler protection may be required for the storage of less than 2,500 tons of ammonium nitrate where location of the building or the presence of other stored materials may present a special hazard.
Conn. Agencies Regs. § 29-349-336