Pumps for Transferring Flammable or Combustible Liquids.

In response to some questions on the issue of pumps and the power source for pumps used to transfer flammable or combustible liquids from containers or portable tanks, clarification of the OFC position and interpretation of the BC Fire Code is offered.

Part 4 of the BC Fire Code deals with transferring of flammable or combustible liquids from containers or portable tanks, whether mounted on trucks or service vehicles or installed in remote areas outside of buildings.

Section 4.11 “Tank Vehicles” is silent about pumping equipment yet the scope of Section 4.11 covers any vehicle with a cargo tank having a capacity of more than 450 L,  (100 gallons) mounted or built as an integral part of the vehicle.

Dispensers at fuel dispensing stations must conform to CSA B346-M “Power-Operated Dispensing Devices for Flammable Liquids”.  Pumps used to transfer flammable or combustible liquids from containers and tanks are required to be designed in conformance with good engineering practice.  Pumps tested and listed by recognised agencies such as Underwriters Laboratories Inc. and Factory Mutual Engineering Corporation are considered to be designed in conformance with good engineering practice.

The power sources for driving these recognised pumps are varied and range from hand operated, electric motors, internal combustion engines and transfer box drives from the vehicle gear box.

Hand operated pumps pose little if any concerns and should be used only for transfer from drums. Electric driven units shall be listed for use with flammable or combustible liquids and are used frequently on tanks mounted on service vehicles.

Internal combustion engines used to drive pumps transferring flammable or combustible liquids have created some concerns in the last few years. However, NFPA 385 “Standard for Tank Vehicles for Flammable and combustible Liquids” recognises this practice and lays out some requirements where internal combustion engines are used to drive pumps.

1. The engine air intake shall be equipped with an effective flame arrester, or an air cleaner having effective flame arrester characteristics, substantially installed and capable of preventing emission of flame from the intake side of the engine in the event of a backfire.
    

2. The fuel system shall be so located or constructed as to minimise the fire hazard from spillage during filling and leakage from the tank or the fuel system.
    

3. The engine shall be so located in relation to the pump that spillage from the pump shall be prevented from coming in contact with the engine or any part or the ignition and exhaust system. Adequate shielding can be provided to attain the same purpose.
    

4. Where the engine is carried within an enclosed space, adequate provision shall be made for air circulation at all times to prevent accumulation of explosive vapours and avoid overheating of the engine.
    

5. The exhaust system shall be substantially constructed and installed and free from leaks. The exhaust line and muffler shall have adequate clearance from combustible materials, and shall discharge at a location that will not constitute a hazard. When engines are carried within an enclosed space, the exhaust gases shall discharge outside of such enclosed space.
    

6. The ignition wiring shall be substantially installed with firm connections. Spark plugs and other terminals shall be suitably insulated to prevent sparking in event of contact with conductive materials. The ignition switch shall be of the enclosed type.

Return to the Office of the Fire Commissioner's menu page