DoYouMeanMe?:
Don’t think flour comes under ADR either and that’s quite easy to make a big bang with.
Correct on both counts DYMM, flour isn’t ADR and definitely does go BANG.
DoYouMeanMe?:
Regarding ullage, I mainly used a small dia tipper tank on a straight chassis and although it was back in the 38t days, cement when at max weight, was only about 1/4 to 1/3 up the tank.
I definitely didn’t know that.
It makes me wonder why the tank needs to be as big as it is…
Or is that some kind of “general purpose” tank that’s good for a variety of products. 
DoYouMeanMe?:
Heaviest stuff I ever found was the powder used in toothpast. Sprinkle it along the bottom of the tank a foot deep and you were fully loaded.
Now that’s really amazing.
I’ve learned a lot from you and houndofhell. Thanks very much to both of you. 