|(a) A nonstandard boiler construction, installed prior
to 1937, shall have a maximum in-service time of thirty (30) years,
unless the following are accepted:
(1) an internal and external annual inspection; and
(2) an annual liquid pressure test of one and one-quarter
times the MAWP held for a period of at least thirty (30) minutes,
during which no distress or leakage develops. At no time, while applying
the liquid pressure test, shall the pressure exceed one and one-quarter
times the MAWP by more than 6%.
(b) Any nonstandard boiler having lap-riveted longitudinal
joints and operating at a pressure in excess of 50 psig (345 kilopascals)
shall have a maximum in service of twenty (20) years; this type of
boiler, when removed from the existing setting, shall not be reinstalled
for a pressure in excess of 15 psig (103 kilopascals).
(c) Any boiler having other than a lap-riveted longitudinal
joint may be continued in operation without reduction in the MAWP.