There are five ways to kill house dust mites. 1. Freeze them for 24 hours (dust mites are mostly water), but warm/cold wash after to get rid of the allergens. 2. Put suspect or infested items in a hot dryer for 12 minutes, (vent must be outside) again, wash after. 3. Hot wash laundry. 4. Poison them with tea tree oil and benzyl benzoate (successfully used in clinical trials) 5. Or dry them up like a raisin using a dehumidifier.
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