As commuters stand, sweating in a packed rush-hour train, or sit silently, seething in gridlocked traffic trying to get to work, they can comfort themselves with the thought that there are scarier ways to commute. One such method is the daily journey to the ‘office’ taken by tower crane operators. They literally face an uphill struggle as they climb to their crane cabs high above the ground at the start of the working day.
Manufacturers have recognised that one way to make life easier for crane operators is to fit the tower crane with an elevator.
There are, according to Moses Buchanan, specialist engineer (lift and crane) – engineering, construction and power at Allianz Insurance, around 10 manufacturers of this equipment operating in the UK. They include Liebherr (LiUP), Potain/GEDA (Cab-IN), Alimak (TLC), Jaso (JL25), and Raimondo (SL20-TC).
Liebherr was one of the early entrants into the market, launching its LiUp tower crane elevator in 2015 (www.is.gd/epuzul), which can whisk an operator up to the cab in around two minutes at the touch of a button.
Hans-Martin Frech, a director of Liebherr-Werk Biberach, based in Germany, explains: “At high hook heights, crane operator lifts are a relief for the crane operator. Liebherr has, therefore, retrofitted the tower sections in such a way that the LiUP crane driver lift can be installed in almost all Liebherr tower sections… So far, more than 200 LiUp crane driver lifts are already in use.”
When it comes to tower crane elevators, the higher the crane, the better the return on investment. However, as Thibaut Le Besnerais, Manitowoc’s global product director for tower cranes, points out: “Value is not only measurable in term of cost – there is also loss of time and operator fatigue, for example.
“The Cab-IN [a tower crane operator lift developed by Manitowoc’s tower crane division, Potain] makes crane access more user-friendly. It provides a safe way to reach the crane cabin and does not discriminate with regards to who can fulfil the job. In other words, it is disability-friendly.” The Potain Cab-IN (www.is.gd/omemuv) was previewed at Intermat Paris in April 2018. The elevator has a maximum weight limit of 200kg, allowing up to two people to use it at the same time. It was developed specifically for Potain top slewing cranes, in partnership with industrial elevator and construction lift manufacturer GEDA.
However, Craig Hook, head of department and chief engineer for McAlpine Lifting Solutions, is not entirely convinced of the need for crane hoists: “I don’t see massive benefits for the majority of tower cranes except where the crane is really tall because, in this situation, they save climbing time…
“It can take 45 minutes or more to climb a very tall crane, which is productive time wasted. However, as the operator climbs a ladder, they will be carrying out the first pre-use inspection, checking the mast bolts. You can’t do that easily and effectively from an elevator.”
Climbing a ladder also keeps the operator fit, he adds. Besides: “You don’t always need to put in a tower crane hoist if you can get there by another means. Where you have a tall crane that is tied to a building, for example, it is better to send the crane operator up inside the building using a construction hoist and then allow them to cross via the top tower crane tie.
“The risk assessment will confirm that it is much better to go up via the building than in an operator hoist that might break down. Besides, you are putting people at risk assembling the operator hoist.”
On top of this, if you add a hoist to the side of a tower crane, it can reduce the crane’s freestanding height “because you are adding extra ‘wind area’” [whereby the wind has more area over which it can exert sideways forces on the crane].
Laing O’Rourke specialist business Select Plant Hire assesses each project on an individual basis. All of its cranes retain their ladders, but an elevator is recommended where an operator must climb more than 40m of mast (that is from the ground, or from an access bridge from the building).
Alex Warrington, business unit leader for Select Plant Hire, explains: “The operator hoist is just one of the ways Laing O’Rourke is changing the way tower crane operators work. We recognise the value of a well-trained and motivated operator whose well-being is properly catered for. It is key to a productive site. Having quicker and safer access in both directions from the cab to site will benefit the operator and the project team.”
Safety in emergency situations is also essential. The Construction Plant-hire Association (CPA) has been working on operator rescue and, after recently surveying UK crane operators and looking at current emergency response, it is updating the current approach in CPA TIN 013 (www.is.gd/pezeju).
According to Select Plant Hire: “It will be critical in an emergency for a site to have a properly equipped, qualified first aider, and ideally one who is comfortable at height, allowing them to attend a medical incident quickly and stabilise the patient. The elevator will expedite that quick response and make for a smoother evacuation from the crane if required.”
BOX OUT: Tower crane elevator rules
The main driver to install a lift in a tower crane is regulation-driven, according to McAlpine Lifting Solutions’ Craig Hook: “Since 2017, [a crane hoist] has been mandatory on all cranes in France where the driver has to climb over 30m. This means a 100m tall crane may not need a hoist if the driver can access the top of the crane from the building.”
Norway, Holland, parts of Germany and Denmark have similar rules. However, adds Hook: “Although the same design rules for access to the crane operating station applies to cranes used in the UK, there is no enforcement regarding provision of operator lifts, nor is there any indication that these are expected.”
He adds that inspections of the entire crane, including an elevator, must be undertaken six-monthly in the UK, as per the Lifting Operations and Lifting Equipment Regulations or LOLER (www.is.gd/ekoyoj). Regulation Nine concerns the detailed and specialised examination of lifting equipment by a competent person.
Allianz Insurance’s Moses Buchanan says the overall
safety standard for this type of equipment is BS EN 81-43:2009 (Safety rules for the construction and installation of lifts – Special lifts for the transport of persons and goods Part 43: Lifts for cranes).
“This document (www.is.gd/giroje) specifies the safety requirements for the construction and installation of power operated lifts attached to cranes and intended for access to workplaces on cranes, by authorised persons. This includes intended use, erection, dismantling, inspection and maintenance.”
This document, which is currently under revision, says that, to achieve a safe installation of a lift on a crane, negotiations need to take place between the lift manufacturer and the crane user organisation about the interfaces (such as lift way protection, supporting structure, power supplies and suitability of alarm devices) regarding the responsibility for the supply of these requirements.