What If Someone Insists That Your Rope Is Too Small?

What If Someone Insists That Your Rope Is Too Small?

CX85 Staging What If

Ok, there are a few directions we could take this article with a title like that, but in the interests of good taste and decorum, we’ll just mention that size really does matter, just once. There - we can move on now...

To the point of the article, just recently, prior to installing some machines in venue “X”, a well meaning and highly experienced rigger pointed out to us that said machines could not be used for an overhead lift, because they were designed to use 3mm steel wire rope.

“Why not?” we reasonably asked, and the answer was “because the law says that the minimum size of wire rope that can be used for lifting is 5mm”

Now, being a pedant (or so I’m regularly and unreasonably accused), my interest is always piqued when someone makes absolute and definitive statements like “the law says...” or “it is common knowledge...” so I made polite enquiries as to which particular “law” made this rather unusual blanket prohibition on well meaning (and apparently misguided) 3mm and 4mm steel wire ropes, which, in certain constructions, are unambiguously described as “Ropes, Steel Wire, For The Purposes Of Lifting”.

It turns out that the “law” in question was the WorkCover Rigging Guide 1995 (ISBN 0 7310 5159 9).

This particular publication (type “Workcover Rigging Guide” into your favourite search engine) is a particularly informative and practical reference document for riggers, and forms the basis of a program of certification for competency assessment for riggers. It is NOT however, a Standard or a Code of Practice and does not form the basis of any legislation relating to the design of the machinery that a rigger may come across in the course of a working day.

It is not “the law” and has nothing to do with the design and certification of complex multi-rope hosting machinery, so any reference pertaining to minimum rope size for “lifting” is advice for riggers, not rules for design engineers.

So what is the difference between the rules for designing hoists and the guidelines for rigging loads from these hoists?

When it comes to designing machines for hoisting loads, the designing and certifying engineer(s) are guided, in Australia, by many Standards to ensure that the machine is safe and fit for purpose, including (but not limited to):

•    AS1418.1-2002, Cranes, Hoists and Winches
•    AS3990-1993, Mechanical Equipment – Steelwork
•    AS1403-2004, Design of Rotating Steel Shafts
•    AS2550.1, Cranes, Hoists and Winches – Safe Use (General Requirements)
•    AS2579-2004, Steel Wire Rope, Use, Operation and Maintenance

Let’s assume that the hoists in question, using a number of 3mm ropes, had been design-reviewed by an appropriately qualified person, and this review concluded that these hoists complied with (for example) AS1418.1-2002.

It would then be appropriate for a qualified rigger to attach a load to one of these hoists, knowing that the hoist was well designed and safe to use, but this is also the point of demarcation between the work of the hoist design engineer and the rigger who is going to use the hoist to lift a load.

The rigger attaching the load would be quite correct in invoking the WorkCover Rigging Guide 1995 and making certain that when attaching a load to the hoist’s load attachment device (bar, hook, etc) with a steel wire rope, it was a steel wire rope was a diameter of at least 5mm, but the size of the rope(s) used in the construction of the hoist has nothing to do with the rigging of the load from the hoist.

Hopefully this will help to bust a bit of a Staging Myth.


Jands Staging provide articles to the "Staging What If" section in CX Magazine. If you have any questions regarding this article then please comment below or email info@jands.com.au.

Bookmark and Share


Please comment using the form below (email will not be displayed)





Please note that your comment will only appear after it has been moderated.


Security key