This particular topic goes back to 2013 when someone posted flyers in a caravan park saying the D-Shackles had to be a yellow pin and rated to an Australian Standard.
This was just in fact someone trying to drum up business at the Brisbane Caravan show the next week. This particular item spread like wild fires across the industry and consumers which were confused about the requirements.
Daniel Sahlberg lead a research project (in his previous role) and identified the standard they are referring to is for lifting and not pulling purposes. However he was able to get guidance from shackle manufacturers and state regulators on the position, which they published in 2014.
Since then I continue to hear this story come up all the time and we even did a segment recently on What’s Up Downunder about it (as below). Yesterday the Administrator of Vehicle Standards in consultation with the Australian Motor Vehicle Certification Board comprising Commonwealth, State and Territory representatives released a guidance document for safety chain connection devices for road trailers road trailers which are up to 3.5 tonnes (3,500kg) aggregate trailer mass (ATM).
Our specification from 2014 now aligns with the guidance document that was released yesterday, known as Circular 0-1-3. This guidance material was developed with the agreement of state and territory regulators in order to provide a uniform approach in Australia to the use of safety chain connection devices. Since there is no legal obligation to comply with this guidance material, if an individual or a company chooses not to follow this material, it is the responsibility of the person or the company to demonstrate to state or territory road authorities that a particular safety chain connection device is appropriate for the combination vehicle.
Click the links for more info
Here is the document link from the government - http://www.gomakesomememories.com.au/CIA/media/Documents/0-1-3-1.pdf
Here is a segment we did on whats up down under a few months ago – WUDU S8E01 Caravan Tips: Busting the myth around D-Shackles
Thanks to the guys from Caravan Industry Australia ,Victoria for supplying information