Characteristics of required quick closing valves.

A remotely actuated quick closing shutoff valve required by § 153.530(n) must: (a) Be a positive shutoff valve; (b) Be of the fail-closed type that closes on loss of power; (c) Be capable of local manual closing; (d) Close from the time of actuation in 30 seconds or less; and (e) Be equipped with a fusible element that melts at less than 104 °C (approx. 220 °F) and closes the valve. [CGD 78-128, 47 FR 21208, May 17, 1982; 47 FR 27293, June 24, 1982]