There are two type of Water Jel, one is for minor burns, the other is good for all types of burns.
The packaging looks nearly the same, so you need to look close.
The first is: Burn Jel, and is for the type of minor burns you describe.
The other is Burn Dressing, which is a sterile gel soaked dressing thats good for 1st through 3rd degree burns.
You of course would never want to put Burn Jel on a serious burn.