Cylinder Overfill and Transport Decision
At the end of a busy day you have recovered R-410A from two systems into a 20 kg recovery cylinder. The cylinder's tare weight is 14.2 kg and its gross/water capacity marking gives a maximum fill. Your scale reads 33.5 kg total. You still have one more system to recover before leaving, and the van is due to cross a public road to the depot. The cylinder feels cold and there is frost near the valve.
1. Assess the fill state of the cylinder and decide what to do before recovering more refrigerant.
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Net refrigerant = gross − tare = 33.5 − 14.2 = 19.3 kg. Recovery cylinders must not be filled to more than the marked fill limit - commonly around 80% of capacity by weight, and never liquid-full. A 20 kg cylinder at 19.3 kg net is at or beyond a safe fill; the frost near the valve and cold body are consistent with a nearly full cylinder under recovery.
I must not add the third system's charge to this cylinder. I would:
- Stop recovery into this cylinder.
- Weigh and record the contents.
- Use a second, correctly rated and in-test cylinder for the remaining system.
- Never overfill; leave ullage for liquid expansion.
Overfilling a recovery cylinder is a pressure and transport hazard and is not permitted.
2. What are the safety and transport considerations for moving these cylinders?
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Safety:
- Cylinders upright, secured, valve caps fitted, protected from impact.
- Not overfilled; contents labelled with refrigerant type and weight.
- Keep away from heat sources; do not allow the cylinder to be heated to speed transfer beyond safe limits.
- Frost/cold indicates liquid refrigerant; wear PPE (gloves, eye protection) to avoid cold burns.
Transport:
- Cylinders secured in the vehicle, ventilated space, valves closed and capped.
- Documentation of the refrigerant carried; recovered refrigerant is treated as a controlled substance and its movement recorded.
- The vehicle and load must comply with dangerous-goods carriage rules where applicable; the driver should be aware of the load and emergency information.
I would also ensure each cylinder is clearly labelled with the refrigerant and quantity before it leaves site.