These requirements cover stationary aboveground and underground precast concrete tanks, and underground vaults.These requirements cover: A Tanks intended for use as primary containment for liquids that are non-destructive to concrete, such as water contaminated with oil, waste water, or similar products; and, B Tanks and vaults intended for use as secondary containment for flammable and combustible liquids.This document is a companion document to CAN/ULC-S656, Standard for Oil-Water Separators. This document is a reference document for manufacturing precast concrete tanks, such as 'Protected Tanks, ULC-S655' and 'Secondary Containments for Aboveground Flammable and Combustible Liquid Storage Tanks, ULC/ORD-C142.20.' These requirements cover below-grade vaults intended for the storage of flammable and combustible liquids in an aboveground tank.

ORD (Other Recognized Document)