Stove

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Stove
If we had to guess, we'd put the refrigerator door handle or microwave keypad ahead of stove dials when it comes to dirt level—but the controls that adjust your range's heat are some of the filthiest places in your home, since you often touch them when your hands are contaminated with food, and they're harder than the fridge door handle or microwave buttons to wipe clean, according to the NSF study. Check your stove's owner's manual for cleaning instructions; you may be able to put the dials in the dishwasher (if not, wash in warm soapy water, rinse well and dry before replacing).