(a) Installation contracted for prior to November 19, 1952, shall meet the following requirements:
(1) Existing arrangements, materials, and facilities previously approved shall be considered satisfactory so long as they meet the minimum requirements of this paragraph and they are maintained in good condition to the satisfaction of the Officer in Charge, Marine Inspection. Minor repairs and alterations may be made to the same standards as the original installation.
(2) The details of the systems shall be in general agreement with Sec. Sec. 76.17-5 through 76.17-20, with the exception of Sec. 76.17-5(a)(2), insofar as is reasonable and practicable. A 6-inch blanket of foam in 5 minutes for tanks and 3 minutes for other spaces will be considered as meeting the requirements of Sec. 76.17-5.