Q. I’ve come across a product that was created to combat the anthrax spore and was later found to be effective against mold as well. It’s fogged throughout the job for 24 hours, with no access allowed. The product is said to eradicate mold, not just put it in a dormant state. Does this work?

A.Mac Pearce responds: Fogging is an appropriate technique for destroying an infectious agent such as anthrax spores. Once they are dead, they can’t cause disease. Mold problems, though, can’t be “fogged away,” because the mold spores are just as irritating dead or alive. While the dead mold spores cannot initiate new growth, they must be physically removed or they will remain inside the building as an irritating component of the dust. Unless the mold is rinsed or vacuumed away, it’s still there, dead or alive. It has been my experience that elbow grease trumps such chemical treatments.