I'll bet the ranch not one safety impact test has ever been performed here to determine safety of those LPG installations.
The tanks themselves are tested and approved by TISI, as per the following:
The relevant section for the tanks is: Mechanical Engineering and Vehicles: TIS 370-2552 (2009) Liquefied petroleum gas cylinder for internal combustion engines, Effective Date : August 8, 2010
BUT, the problem is both the installation, and the follow up ongoing tests at the annual licencing of the vehicle.
The DLT demands the INSTALLATION be re-certified after 5 years. Having just gone through this a couple of months ago, it is a joke, to say the least. Where I had it done they more concerned with providing a photo of the car and the "licenced" operator. The actual testing consisted of spraying some detergent around under the bonnet, nothing more than a visual look of the tank.
It was inspected after it was first installed, and noted in the blue book. They also measured the distance from the back bumper to the tank, which is inside the car.
I have since fitted an inertia switch into the system, which closes the tank solenoid in the event of a crash and cuts off the gas supply.
There is more to this, I will come back to it.