HSE Safety Alert – Vehicles With Air Suspension Systems

The Health and Safety Executive (HSE) has issued a safety alert for those undertaking or responsible for work on vehicles with air suspension systems. This includes motor vehicle repair workshops, roadside recovery professionals and anywhere this work is undertaken.

HSE has investigated a number of serious incidents involving air suspension systems on vehicles. The two core causes are:

  1. The collapse of inadequately supported vehicles
  2. Unintended rupture or release of components from the air suspension system

What are air suspension vehicles?

A variety of vehicles are typically fitted with air suspension systems, including buses and coaches, refuse vehicles, goods vehicles and tankers.

On such vehicles, inflated rubber bellows, otherwise known as airbags, receive air from the vehicle’s air compressor courtesy of a storage system. The airbags replace conventional springs at each wheel or axle, automatically ensuring ride height regardless of the weight of the load being borne.

Air suspension systems components

Image: Health and Safety Executive

 

What are the common hazards related to air suspension vehicles?

Air suspension vehicles are produced by a variety of manufacturers, but they tend to present common hazards. These include:

  • Clearance changing suddenly and unexpectedly as a result of a drop in air pressure, automatic movements or air bellows rupturing or deflating. This presents a crushing hazard to anyone working in such a way where they may become trapped, for example if they are working under the vehicle or between the wheel and chassis.
  • Work on pressurised systems leading to a violent ejection of parts under pressure, and failure of components which may become projectiles.

What has led to the air suspension vehicle safety alert?

HSE has recently investigated a number of what it deems serious incidents involving air suspension systems that have failed. These include fatalities.

The causes of the incidents include:

  • Airbags failing whilst work is being undertaken on vehicles supported by the air suspension system.
  • Unexpected suspension movement occurring whilst work is being carried out on the suspension control system or vehicle sensors.
  • Failure to depressurise the air suspension system during works leading to the pneumatic air bag or associated components ejecting or rupturing.

What action needs to be taken?

HSE is advising that minimal repair work is carried out at the roadside or on third party premises, suggesting that the prime place to undertake repairs is at an appropriately equipped vehicle repair centre.

Repair professionals are also advised to:

  1. Prevent movement of air suspension. This can be achieved either by deflating the system, or by using suitably rated props or stands designed to prevent the chassis from lowering. Air suspension should NEVER be relied upon to maintain the ride height of a vehicle or position whilst access is gained to areas where people may become trapped.
  2. Exhaust the air from the air suspension system before working on it.
  3. Isolate the air suspension system by physical disconnection of the air supply before working on it, avoiding clamping of air suspension pipework as a means of temporary isolation, which is deemed unsecured.

HSE says that undertaking a risk assessment, carrying out a visual check of the configuration and condition of the air suspension system and planning tasks are all vital.

Further detail for vehicle repair professionals, including advice on working specifically on air suspension vehicles, can be found within the HSE alert.

Further information

Safe recovery (and repair) of buses and coaches fitted with air suspension – this specifically relates to buses and coaches, although there are very few differences between their systems and those on other vehicles, making this a relevant resource for anyone involved in the repair and recovery of air suspension vehicles in general.

Health and safety in motor vehicle repair and associated industries – including updated guidance on vehicle lifts covered by the Lifting Equipment Regulations 1998 (LOLER).