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These requirements cover gate valves intended for installation in piping systems supplying water for fire-protection service. Gate valves covered by these requirements are of the outside-screw-and-yoke type or of the nonrising stem type, the latter for installation either above or below ground.
These requirements cover gate valves intended for installation in piping systems supplying water for fire-protection service. Gate valves covered by these requirements are of the outside-screw-and-yoke type or of the nonrising stem type, the latter for installation either above or below ground.