CRYSTAL LAKE – Scott Dunham remembers when you couldn't get away from the smell of perchloroethylene – or perc – the dry-cleaning solvent lawmakers are increasingly regulating.

The strong smell would stay with the clothes after they exited the machine, and dry cleaners used to take the extra solvent and mop the floors with it. The efficiency and safety standards surrounding the machines that use perc weren't what they are now.

"Years ago, you used to walk into a dry cleaner and go, 'Whoa, we're in a dry cleaner,' because you could smell the solvent," said Dunham, who runs Crystal Lake-based Vogue Cleaners with his father, Robert Dunham.