Logistics & Materials Handling Blog

How to Safely fill a forklift LPG Cylinder?

by Paul Hinz
Filed under: Forklifts

A common question our sales team and technicians are asked by forklift operators and fleet managers is how you safely refill a forklift propane (LPG) cylinder to allow a forklift to continuously operate over extended shifts.

In this post we look at how to safely fill a forklift LPG cylinder using a dispenser pump.

Note: LPG cylinders can also be refilled via a decanting method.

Inspection of Cylinder Before Filling

All LPG cylinders must comply with the following requirements, or they can not be filled:

  • Time from the last test date must be within 10 years
  • It must be in good physical condition with no visible dents, gouges, or bad corrosion
  • All valves must be in good working condition
  • The safety relief valve must not be damaged, blocked or corroded
  • The discharge path must not impinge on the valve protection ring
  • Cylinders must have a liquid level/bleeder valve or AFL fitted
1. Forkift LPG Cylinder Valve Diagram

In addition to complying with the above requirements all LPG cylinders must comply with AS 2030.1, AS 2470 & AS 2764 and display the following marking:

  • Manufacturers marks and serial number
  • Specification number
  • Water capacity
  • Original tare mass
  • Original and any subsequent test dates
  • Test pressure (not less than 3.3 MPa (480psi)
2. Forkift LPG Cylinder Markings and Label Diagram

Forklift LPG Cylinder Refilling Procedure (Non-AFL Fitted)

Refilling an LPG Cylinder that is not fitted with an automatic fill limiter (AFL) using the liquid level/bleeder valve must be completed with the cylinder removed from the forklift.

Refilling may be completed with the cylinder in either of the following positions:

  • Vertical position (preferred position) standing upright
  • Horizontal in a rack with the pressure relief valve in the uppermost position

Warning: when refilling no smoking or flame should be within 6m of the forklift.

Refilling Procedure:

1. Safely Park and switch off the forklift ensuring the park brake is applied and all electrical equipment such as mobile phones, pagers and radios are turned off

2. Ensure there are no employees remaining on the forklift during the refilling process

3. Ensure the employee completing the refilling is wearing the correct personal protective equipment including gloves and eye protection

3. Forkift LPG Cylinder Connecting Refilling Hose

4. Turn off service valve and loosen the female ACME from the service valve and carefully disconnect the forklift service hose from the cylinder (A small amount of vapour trapped between the two check valves will escape)

5. Remove the cylinder from the forklift using safe and proper manual handling techniques

4. Forkift LPG Cylinder Safely Removing Cylinder from Bracket on the Forklift

6. Inspect the physical condition of the cylinder for any corrosion or dents, and check that the test date stamped on the cylinder is within the required 10-year period (if not remove cylinder from service)

7. Check cylinder is not full by checking the contents gauge; and also briefly open the bleeder valve to ensure that no liquid is emitted from the bleeder. If only vapour is emitted then proceed with the filing process. If no vapour is emitted, the cylinder may be empty, or the bleeder blocked. Continue with caution, checking for correct operation of the bleeder at a later stage

Note: If liquid is emitted from bleeder valve, do not commence filling the cylinder. Do not rely on the contents gauge to indicate when the cylinder is filled to the correct level. Follow the procedure for an over-filled cylinder.

8. Remove the dust cap from the filler valve

9. Check that the washer in the fill connection is present and in good condition and that there are no foreign objects blocking the fill connection. Also check the condition of the ACME thread

10. Check all cylinder valves for leaks

11. If necessary for the site, open the supply vessel valves

Note: Open valves slowly to prevent the internal excess flow valve slamming shut. At the dispensing control point activate any other necessary controls for the filling process.

12. Start the transfer pump

13. Inspect the hose and dispensing nozzle for any wear, fault, or damaged ACME thread

14. Connect the dispensing nozzle to the forklift cylinder fill valve

15. Open liquid level/bleeder valve 1/2 to 1 turn only. (If more than 1 turn is required, the liquid level/ bleeder valve seat may be damaged and requires repair.)

5. Forkift LPG Cylinder Bleeder Valve

16. Open the dispensing nozzle valve slowly. Remain in attendance throughout the entire filling operation. Do not use any devices to keep the nozzle open. Check the bleeder valve

Note: If neither vapour nor liquid is emitted from the bleeder, then the bleeder is blocked and the cylinder shall not be filled. Place an out of service tag on the cylinder and move the cylinder to a segregated area. Notify your supervisor so that the cylinder can be repaired.

17. Allow filling to continue until a white cloud mist discharges from the liquid level/bleeder valve. This indicates that the cylinder maximum fill level has been reached. Immediately close the dispensing nozzle to stop the liquid LPG transfer

18. Close the liquid level/bleeder valve

19. Stop the transfer pump

20. Vent, disconnect and stow the dispensing nozzle

6. Forkift LPG Cylinder Disconnecting Refilling Hose

21. Check the forklift cylinder fittings for leaks by liberally applying a leak detection solution, with brush or spray bottle, to the following:

  • Service valve threads and spindle
  • ACME check connector valve
  • Liquid level/bleeder valve
  • Pressure relief valve
  • ACME filler valve and thread
  • Percentage gauge.

Caution: The ammonia present in some soaps and detergents can react with brass fittings and cause such fittings to crack after a short period of time. Caution should therefore be exercised when using soap solutions on brass fittings, and all connections should be rinsed thoroughly with fresh water as soon as possible after the application of the soap solution.

7. Forkift LPG Cylinder Leak Testing the Cylinder

22. Refit dust caps

23. Close supply vessel valve/s

24. Refit cylinder into brackets on forklift, using correct manual handling techniques, and secure bracket clips. Ensure the cylinder is in the correct alignment with the pressure relief valve in the uppermost position

25. Reconnect the forklift service hose by connecting it to the ACME check connector on the cylinder service valve

26. Open the service valve and check for leaks

Warning: Never over-fill a cylinder

Follow the instructions in this post to check the condition of your forklift’s LPG cylinder and safely refill it.

For more further information on refilling your forklifts LPG cylinder or to talk about your next forklift purchase contact one of our experts on 13 22 54 or submit an online enquiry.

Interested in warehouse safety? Read our post on 12 ideas to improve warehouse safety.  

Reference List

  1. 2015. Forklift Cylinder Filling By Dispenser Pump. [ebook] Origin Energy, pp.18-23. Available at: [Accessed 6 April 2022].