B-1.1, r. 2 - Construction Code

Full text
8.82. Piping must be backfilled
(1)  with clean or natural sand free of stones compacted mechanically on site in the case of steel piping;
(2)  with crushed stone or pea gravel in the case of fibreglass piping; or
(3)  according to the manufacturer’s instructions in the case of flexible piping.
O.C. 220-2007, s. 1.