Norbert Dentressangle powder tanker job?

Don’t think flour comes under ADR either and that’s quite easy to make a big bang with.

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.

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.