Backdrafting

The reverse flow of exhaust gases or combustion by-products (like carbon monoxide) into an indoor space, rather than venting safely outside as intended. This issue can occur when there is negative air pressure inside a building, often caused by improperly balanced ventilation systems, blocked flues, or exhaust fans pulling air out of the space without adequate replacement air (makeup air). Backdrafting is a serious safety concern because it can lead to poor indoor air quality and exposure to potentially harmful gases