[ujiro]

He's absolutely right. Especially with the types of things used for stripping paint. They will often have low[er than water] boiling points, so hot water from the tap is gonna bring that vapour out and pose risks.

EDIT: even lukewarm water will raise the amount of vapour coming off. The warmer it is the more vapour is going to come. Best to use cold water and try and wipe it off or something.