256.19 Purging.

The purging of water-seal gas holders, waterless gas holders and pressure holders preparatory to extensive maintenance or construction work on holders, valves and pipe connections, shall be done in accordance with the latest procedure recommended by the American Gas Association Committee and accepted by the American Gas Association. As of this date the accepted procedure is dated March 15, 1933.#

This same procedure shall be followed before the holder under repair is restored to service.#