Quick hitch safety explained

There are a number of good reasons for a rethink on the regulation and use of quick hitches – five deaths in two years, one operator in prison and another on a manslaughter charge, all due to accidents related with semi-automatic couplers.

But now the industry is being hit by a barrage of changes: semi-automatics banned on new machines, some contractors unilaterally banning semis and some automatic hitches, changes to European regulations and the prospect of a new ISO standard in three years. Against that background, perhaps it isn’t surprising that confusion abounds and the industry has descended into claim and counter-claim.

The plain facts are that last October the Health & Safety Executive (HSE) implemented a voluntary ban on supplying semi-automatic couplers for new machines in the UK, but existing units remain legal and can be still be fitted to new machines in Europe and beyond. EN 474-1, the European standard for earthmoving machine safety, is being altered to take account of the UK’s ban on semi automatics.

Semi-automatic and some automatic couplers have been banned from the Olympic Park site and Skanska (which suffered a quick-hitch related fatality on one of its sites last December) will implement a similar ban across all its sites from November, with Bovis Lend Lease following suit from the end of the year.

While the UK’s HSE now requires automatic couplers to be fitted to new machines, it says semi-automatics already in service remain legal and are as safe as other hitches if used correctly (see box). Reports indicate that in all the accidental detachments with semi-automatics, the operator has not inserted the safety pin, or has inserted it in the wrong place.

Automatic only

However, two big contractors Skanska (which suffered a quick-hitch related fatality on one of its sites last December) and Bovis Lend Lease have decided to not only ban semi automatics, but also some automatic couplers from their sites. Going forward, both will only allow automatic couplers on their sites that lock onto both pins. Bovis has published specific requirements (below) which it wants the rest of the industry to follow.

This could leave many plant owners with machines that cannot be used on these sites – and possibly others too. However, many in the industry argue that a correctly used semi-automatic is safer than a fully automatic as the operator has to insert the locking pin and in doing so can see if the bucket is correctly attached and if the coupler is worn, broken or jammed by debris. “You can’t do that from the cab”, is the cry from the supporters of semi-automatics and they may have a point as automatic couplers do not have 100% record in preventing unplanned detachments.

This is where the forthcoming requirements by Skanska and Bovis come into play; they specify the use of couplers that not only locate but also lock both pins of the attachment. This means that if either the rear or front pin does not locate correctly, the attachment cannot fall off. So if the operator can pick a bucket up, it can’t then become detached even if the coupler’s hydraulic pipe ruptures.

This is the kind of assurance Skanska and Bovis are seeking and many plant hire companies are willing to retrofit couplers that satisfy these requirements. Several manufacturers can supply couplers meeting those requirements and Malcolm Kent from the equipment manufacturers’ body, the CEA, says purchasers should survey the market before settling on any particular make.

However, plant owners are concerned than the replacement hitch may fall foul of the forthcoming legislative changes.

Kent says the contractors’ requirements are highly unlikely to find their way into the forthcoming legislation. Furthermore, he says those framing the forthcoming ISO standard haven’t yet started talking about quick hitches, so anybody claiming their coupler will meet the requirement are speculating. And, as is usual, when the new regulations do take effect, it is unlikely they will apply retrospectively.

When the regulators do turn their attention to couplers, the UK’s unfortunate accident record and subsequent actions will ensure we are well represented at the table and submissions by companies and bodies in the UK market will carry a lot of weight.

“The ISO standard is currently a bit woolly and needs to be more prescriptive, but mustn’t be design restrictive,” says Kent. He expects coupler manufacturers to have a chance to highlight the strengths of their design to those drafting the legislation.

Correct use advice

The Strategic Forum’s plant safety group working on quick hitch issues has published a statement confirming that semi-automatics remain ‘legal’. A Best Practice Guide will publish later this year. In the meantime, it has highlighted steps contractors, plant owners and other duty holders should be taking when using any type of coupler:

• Check operators have specific instructions for the machine/coupler/attachment combination and confirm the quick hitch is properly engaged after every change. It recommends motivating operators to use the equipment correctly using disciplinary procedures where appropriate and banning practices like ‘pick and place’ (moving attachments without properly engaging the locking devices).
• Site supervisors need to understand what the operator has to do, allow them time to do it and monitor compliance using spot checks. Supervisors also need to keep other workers away from the machine’s working range and prohibit work under the bucket or attachment.
• Ensure machines are in good order and quick hitches are subject to proper regular maintenance with the maintenance team having the proper information.