B-1.1, r. 3 - Safety Code

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210. Aboveground indoor piping that is to contain petroleum products must be supported overhead or be located in a trench; it may not be installed under combustible flooring.
The trench referred to in the first paragraph must have trapped drains or positive ventilation to the outdoors preventing the accumulation of flammable vapours.
The aboveground piping must be located close to the ceiling or beams, or along walls, not less than 1.8 m above the floor.
O.C. 221-2007, s. 1.