Storing Flammable Liquids to be compliant with PSR/PSHR Ontario Requirements

The storage, dispensing and usage of flammable liquids are regulated by fire codes as well as occupational health and safety laws. The regulations allow the storage of flammable/combustible liquids in plants in the following areas:
* specially designed storage rooms, in closed containers only, where dispensing is not allowed.
* Specially designed storage and dispensing rooms, where dispensing is allowed (in this instance, the room must be equipped with explosion-relief walls and meet PSR/ ONTARIO PHSR.requirements).
* Storage cabinets.

This article focuses only on the storage of flammable and combustible liquids in storage cabinets. The cabinets for storing flammable/combustible liquid containers serve the following purposes: the protection of flammable/combustible liquids against flash fires; the prevention of excessive internal temperatures in the presence of fire; and the containment of spilled flammable liquids to prevent the spread of fire.
Flammable/combustible liquid storage cabinets must bear ULC or cUL labels as evidence for compliance to Canadian standards. The cabinets are usually made of metal having a double wall construction with a three-point door latch and a liquid-tight door sill raised at least 50 mm above the floor.
Storage cabinets also are usually equipped with vents, which are normally plugged by the cabinet manufacturer. While cabinet manufacturers may provide facilities for venting, ventilation for flammable storage cabinets is not required or recommended. Venting a flammable storage cabinet is not necessary for fire protection purposes. Flammable and combustible liquid storage cabinets are designed to protect the internal contents from a fire outside the cabinet. An improperly vented cabinet could compromise the ability of the cabinet to protect its contents from a fire.

A maximum quantity of 500 litres of flammable and combustible liquids may be stored in an approved cabinet, of which not more than 250 litres may be Class I liquids. The fire code allows storing up to three cabinets in a fire compartment. A fire compartment means an enclosed space in a building that is separated from all other parts of the building by enclosing construction that provides a fire separation having a required fire-resistance rating.

The best way to identify the boundaries of a fire compartment is to review the architectural drawings of the facility. They would identify fire separations having a fire-resistance rating.
The Compliance of Flammable Liquid Storage and Dispensing is the first listed item in Section 7 of the Occupational Health and Safety Act for Industrial Establishments in Ontario. This part of the Act is know as Pre-Start Health and Safety Review or PSR/PHSR Ontario.