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Marine Machinery Regulations (SOR/90-264)

Regulations are current to 2024-06-19 and last amended on 2023-12-20. Previous Versions

SCHEDULE IXNon-Structural Tanks, Short Flexible Hoses and Rigid Plastic and Fibre-Reinforced Plastic Piping and Components

PART I(Section 4)Design Specifications

DIVISION IApplication

1This Schedule applies to non-structural tanks having a capacity of 4 500 L or less.
2Non-structural tanks having a capacity of more than 4 500 L shall be designed, constructed and installed in accordance with the Hull Construction Regulations.

DIVISION iiSpecifications

Non-Structural Tanks of 4 500 L or Less Capacity
1Non-structural tanks shall
  • (a) be made of steel or other material suitable for the liquid contents, the intended use and location of the tanks in the ship;

  • (b) where carbon steel shell plate is used, be of the following minimum plate thickness:

    • (i) 2 mm for capacity not exceeding 100 L,

    • (ii) 3 mm for capacity not exceeding 1 300 L, and

    • (iii) 5 mm for capacity not exceeding 4 500 L;

  • (c) be fitted with stiffeners so that any unsupported flat surface area does not exceed

    • (i) 0.28 m2 where plate thickness does not exceed 3 mm, and

    • (ii) 0.56 m2 where plate thickness does not exceed 5 mm;

  • (d) be fitted with a suitable clean-out door, where capacity exceeds 1 300 L; and

  • (e) have welded or brazed seams, except that where the capacity is not more than 100 L, a solder having a melting point of not less than 425°C may be used.

2Unsupported flat surface areas for different thickness plates of non-structural tanks shall be determined by interpolation or extrapolation.
3Depending on the size and configuration of a non-structural tank, the tank may be required to be fitted with baffles.
Short Flexible Hoses
4Short flexible hoses shall be used where expansion and vibration may be encountered.
5Short flexible hoses shall not be used in the correction of misalignment, except for connection of boiler fuel burners and other removable components.
6Guards shall be fitted on large diameter pipes to reduce the flow of fluid leakage to within the capacity of the space bilge pumps.
7Guards shall be fitted to prevent contact of leaking fluid with surfaces where a hazard may result.
8Short flexible hoses shall be adequate for intended use.
Rigid Plastic and Fibre Reinforced Plastic Piping and Components
9Except in accommodation spaces, service spaces and control locations, piping and components of rigid plastic or fibre reinforced plastic may be used in
  • (a) domestic and sanitary

    • (i) salt water piping systems,

    • (ii) fresh water piping systems, and

    • (iii) waste water piping systems;

  • (b) scupper systems draining inboard but not led within the boundaries of refrigerated chambers;

  • (c) ballast water and fresh water piping systems situated inside tanks used exclusively for ballast water or fresh water;

  • (d) sounding and vent pipes to tanks used exclusively for ballast water or fresh water in non-passenger ships except for sections above the weather deck;

  • (e) sounding pipes to cargo holds in non-passenger ships; and

  • (f) bilge suction pipes in ships not over 24 m in length.

10Piping and components of rigid plastic or reinforced plastic shall not be used
  • (a) in fire extinguishing piping systems;

  • (b) in flammable fluid piping systems;

  • (c) in boiler feed and condensate piping systems;

  • (d) in bilge and ballast piping systems in machinery spaces except as provided for in subitem 9 (f);

  • (e) outboard of sea inlet or overboard discharge valves; and

  • (f) in other piping systems where the use could compromise the safety of the ship or personnel.

10.1Despite items 9 and 10, plastic piping referred to in sections 114 and 226 of the Vessel Fire Safety Regulations may be used.
11Piping and components of rigid plastic or reinforced plastic shall be protected from
  • (a) vibration;

  • (b) chafing where secured in hangers; and

  • (c) crushing due to overtightening of hanger clamps where they shall be protected by fitting nut-locking or other suitable devices.

12Allowance shall be made for expansion in piping systems.
13Sea inlet and overboard discharge valves shall be of suitable metal construction where connected to rigid plastic or fibre reinforced plastic piping and the piping shall not be installed outboard of the valves.
14When passing through a steel water-tight or fire control bulkhead, a steel spool-piece shall be attached to the bulkhead or deck and, at a water-tight bulkhead or deck a metallic shut-off valve shall be installed immediately adjacent to the spool-piece except that no valve is required on ballast or fresh water piping located within ballast or fresh water tanks.
15Remote controls operable from above the bulkhead deck shall be fitted to the shut-off valve except where
  • (a) the piping on one side of the bulkhead or deck is completely metallic and the valve is fitted to the metallic piping and easily accessible; or

  • (b) two readily accessible valves are installed, one on either side of the bulkhead or deck.

16When passing through a bulkhead or deck material other than steel, the installation shall be such that the fire, watertight and structural integrity of the bulkhead or deck is not diminished due to penetration.

PARTS II to IV[Repealed, SOR/2021-135, s. 77]


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