Which of the following is a method to improve indoor air quality?

Fixing leaks in HVAC systems is a significant method to improve indoor air quality because it directly addresses the efficiency and effectiveness of heating, ventilation, and air conditioning. Leaky ducts can allow pollutants and unconditioned air to enter the indoor environment, reducing the overall air quality. When air leaks occur, the system may work harder to compensate for the lost air, often pulling in air from areas that might contain dust, allergens, or harmful substances, which can negatively impact health.

By sealing these leaks, the HVAC system can operate more efficiently, ensuring that conditioned air circulates properly throughout the space. This not only keeps indoor temperatures more comfortable but also helps to filter and maintain cleaner air. Improving the efficiency of the HVAC system through leak repair also reduces energy usage, making it an environmentally friendly choice.

In contrast, simply reducing air ventilation can lead to stagnant air and a buildup of pollutants, while sealing all windows and doors can trap hazardous pollutants indoors. Limiting air conditioning might cause humidity issues and discomfort, further deteriorating air quality.