Prior to bringing a tank car or tank vehicle into the transfer area, the atmosphere in the area shall be monitored with combustible gas detector to insure that no flammable concentration of combustible gas is present.

An operating test of the plant shall be made at least once each calendar year with a maximum interval of 15 months and a minimum interval of 6 months between operating periods. The department shall be notified at least five days in advance of such a test. Compliance with this requirement can be achieved for those plants which, through system need, must be operated at least once during the annual cycle. If a company does achieve compliance in this manner, no prior notice is required.

Provision shall be made for the safe storage of test equipment associated with calorimeters or calorimixers, such as standard natural gas cylinders or other combustibles, so that their storage and maintenance effectively separates such flammables from sources of ignition.