21. In addition, Strate produces butterfly valves and start-up relief valves for the industry sector. 22. Many fire engines have such relief valves to prevent the overpressurization of fire hoses. 23. So we see the bicycle as a pressure relief valve for the transportation system. 24. Gas-loaded relief valves are controlled by the nitrogen pressure loaded into the relief valve. 25. The emergency pressure relief valve in the tank is called a hydrostatic pressure relief valve. 26. They are equipped with an approved pressure relief valve . 27. The pressure relief valve had been capped, and the tank was partially drained of water, 28. The pressure-relief valve is a device attached to a pipe attached alongside the water-heater tank. 29. An over-pressure relief valve in the first stage is used to protect the output hose. 30. "This means they will know there is a relief valve in Washington, " he said.
