Load Tests - Better Safe Than Sorry


Zipline load testing is the process whereby a flying fox is certified safe for human use. But who does it and when? Can you do it youself? Once proven safe does it have to be done again?

All good questions.

In this article I'll cover everything you need to know about zipline tests but were afraid to ask. You'll understand the difference between Static and Dynamic testing. Also how testing impacts the bottom line for flying fox operators.

First, let's see what the standards have to say.

Prior to first use, a proof test load should be applied to the zip line in the same manner in which it is to be used. A minimum proof-test load of twice the rated capacity is recommended. [AS 2316 ]

Dynamic Tests

This means sending a weight down the line as if it were a person. Obviously if something goes drastically wrong it's better to slay a test weight.

Dynamic testing provides an opportunity to make adjustments. Sometimes after the first run the zipline sits a lot lower. The cable gets stretched and hardware components take up strain.

Everything gets checked for slippage and tightened if needed. A couple of turns of the turnbuckle brings the cable back up to height. Then we give it another run. Rinse and repeat as often as needed until the whole system remains stable. Usually 3 or 4 runs is enough.

For practical purposes we use water drums. If the intended participant weight is 100kg we'll send down 100kg in water weights. This part can be done by an advanced rigger - the minimum qualification needed to work on a flying fox.

Static Tests

With dynamic testing complete we now call in the big guns. Static testing must be performed by a NATA accredited testing authority. We find Fremantle Foundary to be a great resource for this.

As the name implies, this test involves hanging a weight on the zipline and allowing it to just sit there for a few minutes. A measurement is taken at the start to an arbitrary datum. When the time is up the distance is measured again.

The test weight is twice the desired capacity. If there was no movement or "give" in the system then everything is good to go. The zipline has proven itself safe. A certificate is issued and a metal plate stamped with the rated load which must be displayed at the zipline itself.

What it means for Zipline Operators

Testing as above should be done periodically at intervals not exceeding 12 months. To operate a zipline legally it must be re-certified every year. A visual inspection and adjustments by an advanced rigger should be performed every 6 months.

All this ensures that degradation over time does not evolve into a safety hazard.

In 2019 a zipline patron slammed into a tree when the breaking system failed. Injuries were severe. An investigation found the inspection regime to be lacking. Undiscovered wear-and-tear. The result? A $40,000 fine to the business. (Ref: QLD WorkSafe).

It's a no-brainer that regular maintenance is cheaper than potential fines.

Being certified also brings peace of mind. There's no guesswork as to how "heavy" a particpant can be accepted. Avoid a scene when telling someone they can't use the zipline. It's all there in black and white on the compliance plate. No emotion needed. Another reason to display it prominantly at the departure point.

Want to make more money?

Use the figures in your marketing. Being specific promotes trust. Advertise your certification status. And to make more profit just tell the engineers to add more weight. A higher load rating means potentially more clients.