Safe operation of cranes

So, we have mobile cranes erected on sites without the proper installation of the outriggers. And we have tower cranes left loaded with the tools of the trade for a whole weekend, and often even more.

We have lifting equipment operating without the necessary overload alarms. And we have mobile cranes erected on outriggers beneath which a couple of wooden beams have been haphazardly laid to act as blocking.

We will soon have tower cranes prevented from slewing by locking the brakes on the jib. I will soon refrain from going out of my home if this goes on. But then again, if the crane erected nearby collapses, will the safety of my home suffice?

Following the article published in The Times on May 3 regarding the legality of trespassing of private airspace by tower cranes erected near buildings, this locking of the jibs is what one would expect. Without entering into the debate regarding the legality or otherwise of such trespassing, I do hope that the locking of the brakes on the jibs is not an option to hastily solve the problem. In this way, we would be solving one problem and possibly creating several others. My concern is not the legal issue of whether grease drips here or there but rather the more important one of health and safety.

Tower crane manufacturers warn operators against such locking, due to the stresses the crane is subjected to by the wind. Indeed, it is considered indispensable for the jib of an idle tower crane to be left free to rotate, or slew, according to the direction of the wind. In this way, the crane would be presenting the minimum area against the force of the wind, thereby reducing to a minimum the stresses induced in the crane.

We have had instances when tower crane jibs have been locked from slewing and have been destroyed by the action of the wind on their structure. Tower cranes are subjected to enormous stresses due to wind loading, which stresses are considered to be much more than the cranes should be subjected to during operation, if the required alarms are operational, that is.

If a tower crane jib is locked and prevented from slewing, the stiffness of the structure is increased considerably and this can lead to the crane's downfall, literally. The crane jib should be allowed to slew freely and sway under the action of the wind, again reducing the resistance to the wind.

Let us make our roads and neighbourhood safe and remove these hazards and hope that all those entrusted with the operation of cranes and other heavy equipment take care of their, and our, safety.