BFFF contacted the Health & Safety Executive in May to raise concerns about the increased number of reports of failure of LPG vaporisers in fork trucks due to clogging resulting in fire.
HSE has now issued a safety notice after working within their own labs and across the lift truck industry to try to identify the cause.
Outline of the problem
The build-up of deposits in fuel systems, in particular, the vaporiser units of LPG-powered vehicles has led to a number of fires.
Trucks not starting due to sticking valves
Deposits in vaporiser units, flow regulators and shut-off valves cause the truck to fail to start, particularly from cold. The build-up of deposits can lead to sticking valves and the mixture supplied to the engine being too rich to be ignited.
Repeated starting attempts can release unburned LPG
Repeated starting attempts can result in the release of unburned LPG, which in extreme cases can be ignited, setting fire to the vehicle and surrounding materials.
Action required
Operators
- review your safe system of work in relation to the use of all LPG powered lift trucks and similar vehicles
- provide information, instruction and training for all operators about the hazards raised in this alert
- park LPG vehicles in well ventilated areas free from flammable material, particularly when parking overnight or for longer periods
If a truck does not start within the normal few seconds
- do NOT continue to turn (crank) the engine over using the starter
- do NOT repeat the normal engine starting procedure
- do NOT spray volatile agents into the air intake in an attempt to aid starting
- get off the truck and close the shut off valve to isolate the gas bottle
- secure the truck to prevent further starting attempts
- ensure the area is well ventilated
- do NOT attempt to solve or repair the problem yourself, arrange for a competent maintenance engineer to do a check of the LPG system
Service and maintenance engineers
If you are presented with an LPG powered truck with a starting problem:
- do NOT follow the normal starting procedure
- isolate the LPG supply by closing the shut off valve
- ensure that the area is well ventilated
- disconnect the battery
- release LPG pressure trapped in the fuel supply system
- follow the manufacturer’s guidance for inspection of the LPG system
LPG is cold, take appropriate precautions when working with it. Once released LP gas is heavier than air and can pool in low lying areas, where it can be ignited by any source of ignition, including static electricity, electrical sparks and hot surfaces.
Guidance
Relevant legal documents
Regulation 12 of the Provision and Use of Work Equipment Regulations 1998 (PUWER) requires that the risks to users from work equipment catching fire are adequately controlled.
The problem is not limited to a single truck manufacturer, but appears to be geographically limited to the UK.
We have also been made aware of some aftermarket suppliers of replacement hoses might not always be providing the correct LPG grade hoses. Plasticizer additives in incorrectly specified elastomer hoses, e.g. hydraulic hose, can be leached out of the hose through contact with the LPG, thus increasing the amount of contamination and leading to a failure mode difficult to distinguish from that associated with poor fuel quality. Whilst we don’t have any evidence that incorrectly specified hoses have played a part in any of the failure/incidents, it is essential that only LPG grade hoses are used in LPG systems and this can best be assured by use of original OEM parts.
It is important that such incidents are reported under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations places a clear obligation on the site to report explosion/fire which takes a piece of plant out of service for more than 24 hours under RIDDOR.
The UKMHA has released the following safety alert:
UKMHA Release LPG Safety Alert – The UK Material Handling Association
+ 44 (0) 1400 283090
June 8th, 2023.
+ 44 (0) 1400 283090
