Hull Construction Regulations

235 (1) Subject to subsection (2), no duct provided for the ventilation of a machinery space of Category ‘A’, galley or car deck space shall pass through an accommodation space, service space or control station unless the duct is

• (a) constructed of steel that,

  • (i) in the case of a duct that has a diameter or width of 300 mm or less, has a thickness of at least 3 mm,

  • (ii) in the case of a duct that has a diameter or width greater than 760 mm, has a thickness of at least 5 mm, or

  • (iii) in the case of a duct that has a diameter or width greater than 300 mm but not greater than 760 mm, has a thickness determined by interpolation;

• (b) suitably supported and stiffened; and

• (c) insulated to an ‘A-60’ Class fire rating throughout the accommodation space, service space or control station.

(2) A duct provided for the ventilation of a machinery space of Category A, galley or car deck space may pass through an accommodation space, service space or control station if the duct is

• (a) constructed of steel;

• (b) fitted close to every boundary penetrated with a fire damper that is

  • (i) of the fail-safe automatic closing type, and

  • (ii) capable of being manually operated from either side of the division; and

• (c) insulated to an ‘A-60’ Class fire rating from the machinery space, galley or car deck space to a point at least 5 m beyond each fire damper.