You must:

• Provide at least one automatic fire extinguishing system or an automatic dip tank cover if the tank:

– Holds one hundred fifty gallons or more of liquid

– Has four square feet or more of liquid surface area.

• Make sure automatic fire extinguishing systems or automatic dip tank covers meet the requirements of Table 1.

Exemption:	An automatic fire extinguishing system or an automatic dip tank cover is not required for a hardening or tempering tank that:
	• Holds less than five hundred gallons
	or
	• Has less than twenty-five square feet of liquid surface area.

Table 1: Automatic Fire Protection System Requirements

If you provide:	Then you must:
An automatic fire extinguishing system	• Use extinguishing materials suitable for a fire fueled by the liquid in the tank
	• Make sure the system protects the:
		– Tanks
		– Drain boards
		– Stock over drain boards.
A dip tank cover	• Make sure the cover is:
		– Closed by approved automatic devices in the event of fire
		– Able to be manually activated
		– Kept closed when the tank is not being used
		– Made of noncombustible material or metal-clad material with locked metal joints.