Whether you're dealing with bad smells in memory foam or foul odor from couch cushions, getting a bad smell out of foam is much harder than practicing a few preventative techniques. But fortunately, when changing sheets or cushions and keeping them clean has failed to keep smells out, or when your expensive foam mattress topper has a close encounter with bodily functions or ends up smelling like cigarette smoke, there are a few things you can try.
Allow your foam mattress, mattress topper, pillow or cushions to air out in a well-ventilated area for at least 24 hours. This will help to dissipate any remaining chemical odors.
Treat any remaining odor by sprinkling baking soda liberally over the foam and letting it sit overnight in a well-ventilated area.
Vacuum the foam thoroughly with a hand vac or the soft brush attachment on a vacuum cleaner.
Turn the foam over and sprinkle the other side with baking soda, too. Let sit overnight, in a well-ventilated area, once more.
Vacuum the foam again. You can repeat the sprinkling and vacuum process with baking soda if necessary. You can also spritz the foam with either vinegar or a citrus-based cleanser, let dry, and then vacuum thoroughly.