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• also known as back-drafting
  • occurs when negative pressure in the house draws products of combustion into the house.
  • a concern when there are combustion appliances in a home
  • usually caused by over ventilation and a home with low natural air-changes
  • toxic compounds can be present in combustion gases, the presence of these gases in household air can lead to problems ranging from nuisance headaches to serious illness, carbon monoxide (CO) poisoning and even death