Text in force at 23-63: from 23-43, effective 10 May 1993.
[Each exhaust-heated, induction air preheater must be designed and constructed to--
(a) Ensure ventilation of the preheater when the induction air preheater is not being used during engine operation;]
(b) Allow inspection of the exhaust manifold parts that it surrounds; and
(c) Allow inspection of critical parts of the preheater itself.
58 FR 18974 · Source