Section 096-133-2 - DefinitionsA. Loading rack."Loading rack" means the loading arms, pumps, meters, shutoff valves, relief valves, and other piping and valves necessary to fill gasoline tank trucks at bulk gasoline plants.B. Vapor balance system."Vapor balance system" means a closed system that allows the transfer or balancing of vapors, displaced during the loading or unloading of gasoline, from the tank being loaded to the tank being unloaded.06- 096 C.M.R. ch. 133, § 2