Glen Duff responds:
Good news, indeed. Still, you need to make sure you're wearing your dust masks when working with that stuff, especially if it's been around long enough to accumulate dried mouse droppings, hairs, urine. Nasty critters and their leavings are best left out of yourlungs, as is the dust from the rock wool.
Charlie Self "Adam and Eve had many advantages but the principal one was that they escaped teething." Mark Twain