Construction Safety Alert on Quick Hitch Devices for Excavators

HSE is issuing a safety alert to users of excavators fitted with quick hitch devices.  There have been a number of serious incidents in the construction industry, including four fatalities since December 2006.  This alert outlines the precautions which need to be taken with these devices.  The initial enforcement expectations for HSE inspectors will be to take robust enforcement action where quick hitches are found to be in use without adequate precautions.

A quick hitch on an excavator is a latching device that enables attachments to be connected to the dipper arm of the plant and changed quickly.  Quick hitches are in common use throughout the construction industry and, when properly designed, maintained and used can save a great deal of time when working with excavators.  They allow operators quickly to use plant for a wider range of tools than just buckets, such as mechanical diggers and piling drills.

The four fatal incidents in the last 12 months were all using semi-automatic quick hitches, but there have been accidents involving both manual and automatic types in the past.  There are many different types of quick hitch but the common theme through all of these fatal incidents was a missing retaining pin or bar.

The pin holds the attachment in place against the quick hitch and insures against accidental release.  Often a quick hitch may still operate for some time without the retaining pin in place and then suddenly, without warning will swing open or fall completely off.  If this happens when lifting over / close to a person then the result is likely to be fatal.

Those in control of work should ensure that adequate precautions are in place.  The precautions to be taken should be identified by a comprehensive risk assessment and should include:

• Excavator operators should be adequately trained on the use of quick hitches in general;
• Excavator operators should be competent to use the specific hitch on the machine they use;
• The manufacturer-supplied retaining pin must be available on the machine;
• Ad-hoc replacements of pins with large bolts wire or other substitutes should be forbidden in all circumstances;
• There should be a system for checking that the pin is in place on the hitch before starting the work and every time a different attachment is fitted;
• Operators should be instructed not to use the machine unless they are satisfied that the quick hitch is secured in place.  If the operator cannot see from the cab of the vehicle due to poor weather then s/he must visually check from the ground;
• Those in control of sites should undertake random checks to ensure the precautions are being implemented.

Additional advice on good practice

• Where there are loose pins or clips which may be easily lost, they should be retained or attached to the quick hitch.
• The area around safety pin insertion holes can be painted to make it clear to operators and site supervision where the pin should be inserted.  Likewise pins can be painted to make them more visible.
• Some duty holders have modified the safety pin so that it cannot be fully removed from the hitch.  Duty holders should always check with the manufacturer before modifying the hitch.
• Safe systems of work should ensure that others are not exposed to risk by working below the bucket, for example, ground workers in excavations.