(a) Each duct for ventilation of Category A machinery spaces that passes through accommodation, service, or control spaces must be:
(1) Constructed of steel and insulated to “A-60” Class; or
(2) Constructed of steel, fitted with an automatic fire damper at each boundary where it enters and leaves the Category A machinery space, and insulated to “A-60” Class for a distance of 5 meters (16.4 feet) beyond each machinery space boundary.
(b) Each duct for ventilation of accommodation, service, and control spaces that passes through Category A machinery spaces must be constructed of steel and be fitted with an automatic fire damper at each Category A machinery space boundary.
authority: 46 U.S.C. 2103,
3306,
3703,
3719; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; Department of Homeland Security Delegation No. 0170.1; Subpart 32.59 also issued under the authority of Sec. 4109, Pub. L. 101-380, 104 Stat. 515
source: CGFR 65-50, 30 FR 16671, Dec. 30, 1965, unless otherwise noted.
cite as: 46 CFR 32.56-60