Poor indoor air quality in homes from combustion in poorly ventilated spaces is mainly due to which gas?

Poor indoor air quality in homes from combustion in poorly ventilated spaces is mainly due to which gas?

• A. NO2
• B. O3
• C. SO2
• D. CO

Answer: (D)

When fuels burn in a poorly ventilated space, combustion is often incomplete, producing carbon monoxide rather than carbon dioxide. Carbon monoxide is colorless and odorless, which makes it hard to notice without a detector, so it can accumulate indoors. It binds to hemoglobin in the blood far more readily than oxygen, forming carboxyhemoglobin and reducing the blood’s ability to carry oxygen to body tissues. That disruption to oxygen delivery explains symptoms like headaches, dizziness, and, in severe cases, unconsciousness or death. The other gases listed can be present in some combustion scenarios, but they are less central to the everyday indoor air quality issue from burning fuels in homes with poor ventilation.

When fuels burn in a poorly ventilated space, combustion is often incomplete, producing carbon monoxide rather than carbon dioxide. Carbon monoxide is colorless and odorless, which makes it hard to notice without a detector, so it can accumulate indoors. It binds to hemoglobin in the blood far more readily than oxygen, forming carboxyhemoglobin and reducing the blood’s ability to carry oxygen to body tissues. That disruption to oxygen delivery explains symptoms like headaches, dizziness, and, in severe cases, unconsciousness or death. The other gases listed can be present in some combustion scenarios, but they are less central to the everyday indoor air quality issue from burning fuels in homes with poor ventilation.