(a) The alarm required by Sec. 72.15-15 (c)(4) of this subchapter, which indicates the loss of required ventilation in spaces specially suitable for vehicles, shall be marked with a conspicuous sign in at least \1/4\-inch letters ``VENTILATION FAILURE IN VEHICULAR SPACE.''
(b) [Reserved] [CGFR 66-33, 31 FR 15284, Dec. 6, 1966]