
Bulk Fuel Loading Safety Procedures
It’s important to use basic safety practices during bulk fuel loading operations. Every facility is unique and should be evaluated according to guidelines outlined in NFPA®, ANSI® and local and regional codes and statutes. Bulk fuel facilities should implement the following safety practices, at a minimum.
Tank Truck Parking During Loading
- Tank trucks with Class I liquids should be parked at least 25 feet from above-ground tanks, warehouses, buildings and property lines
- Tank trucks with Class II and Class III liquids should be parked at least 15 feet from the above entities
- Open flames and smoking should not be allowed within 25 feet of fuel-transferring operations
Vehicle and Driver Guidelines
- Shut off engines and set parking brakes before beginning any fuel transfer
- All inspections, recordkeeping and testing should comply with Department of Transportation (DOT) guidelines
- Review motor vehicle records annually for all current drivers and before assigning newly hired personnel to driving positions
Loading Procedures and Static Bonding and Grounding
Top Loading—Static electricity is created by a build-up of differently charged ions and occurs naturally when objects (including liquids and gases) move against one another. This type of build-up can take place when liquid products are top loaded into tanks. The build-up can produce a static electrical spark between the loading nozzle and the tank opening or cover.
If flammable vapors are present when the spark occurs, an explosion or fire can happen.
- Use a static bonding cable when flammable or combustible liquids in temperatures above the flash points of the liquids are transferred between containers to equalize the static electrical charge and prevent a static spark
- Before loading tank vehicles through open dome covers, make a bonding connection between the loading tank and the vehicle or tank before dome covers are raised
- Keep connection in place until filling is completed and all dome covers have been closed and secured
- The static bonding and grounding cables should be connected to the loading piping, tanks and a metal stake installed at least 7 feet into the earth
Bottom Loading—An automatic shutoff system should be used when bottom loading a tank vehicle to ensure that only a predetermined quantity of liquid is loaded and to prevent overfilling. All connecting components between the loading rack and the tank vehicle must be functionally compatible. The loading hose or pipe and the truck should only be connected by a dry disconnect coupling.
Unloading Risers—All unloading risers should be equipped with backflow check valves to prevent the product from flowing out of the bulk plant. The unloading risers should have substantial support between the backflow check valve and the end of the riser that connects to the transport. This support should be able to withstand a “pull away” from a transport while the hose is still connected to the unloading riser.
Self-Closing Loading Riser Valve Operation Safety
Self-closing loading riser valves should be used to control the flow of liquid when top-loading a tank vehicle with Class I or Class II liquids. These valves can be operated by either manual or automatic shutoff systems. Automatic shutoff systems should have a manual shutoff valve at a safe distance from the loading nozzle, in case the automatic system fails.
Fill Extensions with Open-Dome Vehicles
Use a fill extension downspout that extends to within 6 inches of the bottom of the tank when filling open-dome vehicles in which a flammable range vapor/air mixture could exist.
Electrical Equipment Requirements
When Class I liquids are being handled, all electrical equipment within 3 feet of the fill connection should be Class 1 Group D, Division 1 rated. Use Division 2-rated electrical equipment when Class I liquids are being handled between 3 and 15 feet of the fill connection.
Wiring of this type is commonly referred to as “explosion proof” and uses ridged, threaded conduit. This type of wiring should be used for all lights, motors, switches, phones and other electrical equipment within the distance requirements.
Fuel Transfer Pump, Piping and Switch Organization
Pumping and piping equipment for each class of liquid should be separated to avoid cross-contamination. All switches and piping should be labeled or color-coded to indicate the type of product they contain or control.
Fuel Tank Containment Dikes
Tanks containing Class I or II liquids should be surrounded by a dike constructed of earth, steel, concrete or solid masonry, and designed to be liquid tight in order to withstand the full hydrostatic pressure of the liquid. The capacity of the dike should not be less than the capacity of the largest tank within the dike.
Bulk Fuel Plant Fire Prevention and Control
Precautions should be taken to prevent the ignition of flammable vapors. Make sure all fire safety equipment is well-maintained and in working order.
- Ignition sources should be removed or strictly controlled within 25 feet of fuel transfer operations, while driving the vehicle or when making repairs
- Equip bulk fuel plants and tank trucks with fire extinguishers with a minimum rating of 40 B
- Post No Smoking signs at the loading rack, unloading risers, tanks and at all access points throughout the plants
Liquid Containment—All tanks should have a way to contain liquid in the event of an emergency fire. This can be accomplished by having an actuated valve that snaps shut in the event of a fire, or by always keeping the valves and covers closed.

Disclaimer: This material is designed and intended for general information purposes only, and is not intended, nor shall be construed or relied upon, as specific legal advice.
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