1 Mar 2010

Scissor lift failure in motor vehicle repair facility


The following safety bulletin has been issued by the HSE regarding potential concerns with a short-bed scissor lift used in motor vehicle repairs. If you use this type of equipment within your garage please check for signs of damage. Don't forget you can get your pre-use inspection systems from Good to Go Safety to help ensure a regular check is carried out on your MEWP to help maintain a safe workplace.

 Introduction:

This alert concerns short-bed scissor lifts manufactured by Texo, which may also be badged as Hofmann. It is issued following the catastrophic failure of a 10 year old machine used in a motor vehicle repair (MVR) facility. Although no one was injured, a failure of this type with an operator working below or nearby is potentially fatal.

The failed lift was labelled as Hofmann Genius PSC3 with a safe working load of 3 tonnes and is shown in photographs 1 and 2. A similar model is shown extended in photograph 3.  It had been maintained and subject to thorough examination and testing.

Examination of four identical lifts at the premises revealed similar cracks at the same position such as that shown in photograph 4.  Since the incident HSE has received a report from another premises of similar cracks on a Hofmann PSC3 scissor lift

Background:

Scissor lifts can be either short bed or long bed, and either be recessed into the ground (as in the photos below) or surface mounted. Short-bed scissor lift platforms make contact with the vehicle body between the front and rear wheels e.g. through contact with the seam between the floor panel and sill. The lift may have accessories such as profiled rubber lifting blocks, which provide a slot for the lifting point and reduce the height at which the lift commences raising the vehicle. Long-bed scissor lifts have platforms, similar to four-post lifts, which support the vehicle wheels.

The type of in-ground short-bed scissor lift that failed closes so that the platforms are flush with the floor. Considerable force is necessary to open the lift from this fully-closed position, but is within the design load.  To prevent overloading, the weight of the vehicle should not be taken by the platforms until they have been raised out of the floor into their designated lifting position (which allows for insertion of the supplied profiled block).  

Scissor lifts are less common than two-post or four-post lifts in MVR but there are believed to be at least 1000 short-bed scissor lifts in the UK in all types of MVR facilities including tyre and exhaust fitting premises. There are possibly several hundred lifts of this particular model, some labelled as Hofmann but all manufactured by Texo in Italy

Texo believe that the failure may have been caused by the user inserting non-standard items such as wooden blocks as shown in photograph 6.  This causes the load to be applied before the platform has risen to its lifting position and significantly increases the force exerted on the pivots - potentially in excess of the design strength.  They have amended their instruction manual to say:

This instruction must be followed to avoid damages to the Lift:
  • The lift must be raised at least 150mm out of the ground before taking the load.
  • Only use the rubber blocks supplied with the lift.
  • It is important NOT to use any other means to decrease the distance between the lift platform and the lifting point of the vehicle.


Surface-mounted short bed scissor lifts and all long bed scissor lifts are designed to support the load from any position so the supplier believes they should not experience this type of overloading.
Theoretically, the risk of overload through incorrect use could apply to any in-ground scissor lift but HSE is not aware of problems with other manufacturers' machines.

Action taken:

The original UK supplier of the lifts is no longer in business so it is difficult to trace all users. The current supplier, however, is aware of the failure and has notified both their existing customers and the manufacturer.  In addition, the Garage Equipment Association, GEA, have informed other lift-supply companies about the incident.
The bodies who represent organisations carrying out vehicle lift inspections, the Safety Assessment Federation (SAFed) and the Independent National Inspection and Testing Association (INITA), have informed their members.

Action required:

  • Texo-manufactured short-bed scissor lifts should be checked for cracks in the lifting arms. If cracks are found, immediately take the lift out of use and arrange for it to be re-examined by a competent person.
  • Do not use non-standard blocks for lifting the vehicle as this may place an excessive load on the lift.
  • Adhere to the manufacturers instructions not to allow users to be under, or in close proximity to, the lift during raising and lowering. 
  • All scissor-lifts used for lifting vehicles in MVR should be thoroughly examined and tested by a competent person every six months.
  • Any failure of a vehicle lift or any load-bearing part must be reported to HSE as a Dangerous Occurrence under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 1995. 

 Bulletin No: OPSTD MS 2-2010
(Reproduced under the terms of the Click-Use Licence).

No comments:

Post a Comment

Powered by Blogger.