14.03.2013

Safety bulletin updated

UK based contractor Bam Nutall has issued an update to its previous safety bulletin regarding a JLG 450AJ which lifts the temporary restriction it placed on these units.

An investigation into the incident by the contractor with the assistance of owner A-Plant and JLG revealed that the cylinder was damaged or overloaded prior to the buckling incident that caused the safety alert to be issued. Click here to see the original report

The bulletin itself is well written and concise so it probably best to simply publish it in full here.

"Update on Hydraulic Ram incident

Following the issue of Safety Alert reference LC401-LTR-APK-HS-COM-0001 relating to an incident involving a hydraulic ram on the JLG Model 450AJ Boom Lift, a review of available information has been undertaken by a team consisting of BAM Nuttall, A-Plant and JLG representatives. The following update, to the previously issued Safety Alert, Reference: LC401-LTR-APK-HS-COM-0001 can now be released:

Whilst there is no evidence that the operator worked outside of the permitted working parameters and a definitive cause for the incident cannot be confirmed, damage of the slave level cylinder rod on the above referenced model was most likely caused by an overload event which occurred sometime prior to the buckling of the rod.

The overload and initial distortion could have been caused by either impact of the platform into the ground, overload of the platform, a significant dynamic force when driven over an obstacle exceeding normal usage parameters or an accumulation of effects from minor instances.
The levelling rod is most exposed when at low level in travel mode; it would be unlikely that this incident would occur when at height and with the rod retracted into its cylinder.

The cylinder remained attached to the machine, as designed, and due to site and manufacturer requirements being followed by the platform occupants, in the wearing of appropriate fall protection, any associated risk was appropriately mitigated.

It is considered that the risk of a repeat event is low. It is advised that the initial restriction placed on JLG manufactured 450AJ boom lifts is now lifted.

Lessons learned from this occurrence are:

1. Operators should ensure that daily checks include inspection of the rod and cylinders. If any cylinder rod damage is suspected, place a rule on the cylinder rod to ensure the rod is not out of alignment.

2. Travel speed of the machine should be appropriate for the site conditions and should be set to "slow" when operating on uneven surfaces as noted in the Operation and Safety Manual.

3. Platform positioning should be adjusted to prevent impact with the ground whilst driving.

4. Operators to record any occasions of the overload alarm activation on the daily inspection form and to notify the supervisor of activation.

5. This incident demonstrates the importance of wearing the appropriate harness and lanyard.

Please ensure this notification allowing the use of this model to continue, on the QEOP project is passed on to the supply chain and associated parties.

Vertikal Comment

While the contractor was probably quite right in issuing some sort of safety bulletin, it does show how modern communications can and should play a part in making a local incident global. After all if there was a real danger here then everyone should be alerted equally – not just the contractors own staff.

However it also demonstrates the importance of an immediate and thorough investigation - and ‘thorough investigation’ does not mean one that takes a long time or one that involves eminent chairmen. Unless detailed metallurgical tests are required, very little is learned after the first 24 hours. In fact recollection and ‘facts’ begin to change within hours of an incident.

In this case the odds were always strongly in favour of a prior impact or other form of overload, and the risk of a similar failure at height was very minor and the chances of a catastrophic one negligible. While the parties acted in good faith here, faster action could have resulted in a bulletin more like this one, rather than a product suspension.