Lars Andersson, Hiab structural mechanics design manager explains what happened. “I know of three accidents, all fatal, from 2004. The operator was very close to the boom tip, and was trying to move the jib out, so he should move the lever out. But he moved it the wrong way—he moved it in—and the boom hit him and pressed him harder and harder against the control lever. He could have pressed the emergency button, but when this happens, you panic, and you don’t think logically. He killed himself in a very bad way. The more the boom pressed him against the lever, the more oil was fed to the boom, and the more the operator was crushed.”

“Although they were not our cranes, they could have been,” he says. He adds that in meetings of the European loader crane design standards committee under CEN TC 147, of which he is a member, members decided against flipping the valve block upside down, so the levers work in the opposite direction. They were concerned that if operators worked on multiple cranes in different parts of the world, they might not be sure which way to move the levers.

The Hiab Operator Protection System uses a series of sensors to create a limitation zone around the control lever station that the crane boom cannot reach. The height of the zone, factory set at about 2.5m, is determined by sensors on the main boom and jib that measure their angle. The crane’s Space computer system calculates the maximum possible crane extension and stops the motion when it enters the control zone.

Sensors mounted on the base of the rack-and-pinion crane column measure either side of the limitation zone. An induction sensor mounted on the column reads a steel collar that surrounds the boom, which has had notches cut into it. If it senses the collar, it allows the crane to work. If the collar has been cut away, the sensor’s signal stops the crane. All of the dimensions of the safety area can be adjusted after purchase.

The system can only be disabled by pressing and holding down a release button positioned close to the control levers on the valve side. For cranes fitted with an operator platform, the system is activated as soon as the operator steps onto the platform, and deactivates as soon as he steps down from it.

“Hiab’s safety focus builds upon the belief that loader crane accidents should not be allowed to happen. Comprehensive operator training is essential, but beyond that Hiab has committed itself to developing safety technologies that permit operators to focus totally on their job,” says Andersson.

&#8220Lars Andersson, Hiab”

“The operator safety systems for control platforms that started when the Machinery Directive was enforced in the mid-90s were quite bad. There were different solutions in different countries. No-one really knew what [objectives] to fulfill. They were bad until 3-4 years ago.”

During a two-year trial in Australia, Hiab sold about 500 units. The company is now marketing the safety feature in Europe.

“Safe ‘cut out’ on the OPS has been an asset when working at close quarters, particularly as I am on my own on delivery most of the time,” says Hiab customer David Greig, delivery driver at Broadview Fencing, in Wingfield, South Australia.

Andersson says whether the equipment is offered as standard equipment or not will vary from country to country (although it will be offered as standard equipment in Australia). It adds an additional EUR1000-EUR1500 to the crane’s cost. Although the system can be offered with cranes with remote controls, the main market is the manually-controlled 5tm-15tm capacity range, with a maximum of about three hydraulic extensions. The system is not available for Jonsered scrap-handling cranes, a sister crane line, because Jonsered lacks the required Space control system. But nothing is impossible, says Andersson: “Technically it is no problem to do it. First someone has to say, ‘We want it.'”

Operator protection systems for operator control stations are now a common option on many loader cranes. “When you are on the platform, above the slewing cylinder, you can see well. It is common in digging. There is a higher risk that you can hit yourself with the boom.” The first safety systems for loader crane operator platforms that came out in the mid-1990s in the wake of the European machinery directive were poor, Andersson says. “There were different solutions in different countries. No-one really knew what to do.”

Only in the last few years have the systems improved, he says. The new system comes from an operator platform safety system originally developed in 2004. Andersson says that this system is different, because it specifically protects operators working crane levers to the side of the crane.