Abstract: A fill block is provided for a CNG fuel system for a transit bus or similar vehicle. The fill block includes a integral one piece body having first and second ends defining a length therebetween. The body has a main bore defined therein. A ball valve is received in the body and has a handle extending from the body. The ball valve is movable between open and closed positions, wherein the main bore is opened and closed, respectively. A fueling port is defined in the body and communicated with the main bore. A defueling port is defined in the body and communicated with the main bore. A fueling receptacle is connected to the fueling port. A defueling receptacle is connected to the defueling port. A defueling valve is provided for selectively communicating the defueling port with the main bore or isolating the defueling port from the main bore.

Abstract: A safety relief system for a CNG fuel supply of a vehicle includes first and second Type 4 cylindrical tanks, each having a shutoff valve at a first end and an outlet at a second end of the tanks. First and second relief devices are attached directly to the shutoff valve of the first and second tanks, respectively. Two separate relief outlet lines are connected to the outlets of the tanks. A common relief line is located generally parallel to and lying between the first and second tanks. The two separate relief lines are both connected to the common relief line. Third and fourth relief devices are connected to the common relief line. Each of the relief devices is constructed to relieve pressure on both the first and second tanks in response to either an excessive pressure or and excessive temperature at that relief device.