Sidevalve:
Given that I’ve probably seen more containers on their sides than any other form of trailer except bulk waste, i wouldn’t put too much faith in that.
There’s only one person to blame when that happens, the driver.
It’s not hard to secure a container or even to drive appropriately.
chester:
Yeah I agree a visual check may not find illegal drugs.
We were talking about containers and rollovers! 
Not checking your load for example, a CNC milling machine on one side, and 20 boxes of pot noodles on the other side.
Just because a box has a seal doesn’t make it safe.
Indeed, but it’s not the drivers responsibility to load it safely, unless he does actually load it!
The driver is responsible for securing the container on the trailer (if he can’t do that then he shouldn’t be allowed near a toy car let alone anything bigger), checking the given weight does not overload axles/GTW and how he drives.
Back to Curtains…
All I have been able to deduce from what VOSA are implementing is that curtains, regardless of whether they are load bearing or not, are not suitable for load restraining.
That is moving the goal posts contradictory to EU/BS standards on load bearing curtains.
The future…
The whole subject of palatalised loads and securing of said loads needs clarifying in a standard easy to read (understand?) format.
Also some of the responsibility needs to be moved from the driver alone.
Securing the product to pallets should be the responsibility of the warehouse/factory/loader.
The securing of the pallet to load bed should be the responsibility of the driver.
The driver would still have to be responsible for refusing pallets that are clearly not following the guide lines, i.e. a 150kg water pump secured to a pallet with string (exaggeration for clarity).
LIKE THAT’S EVER GOING TO HAPPEN
There are far to many combinations of loads, pallets, IBC’s and too many people making to many interpretations of the rules/laws/guide lines to get a correct answer. We are vulnerable to whoever at VOSA stops us and how he reads it and all the BS strapping does is set a standard that he will apply to every curtain sided vehicle whether that strapping was correctly done or not.
Personally I stay away from curtains where ever possible, it’s the only way (for now).