When HVAC systems fail to perform these roles, they allow stale, polluted air to remain in the building. Common causes of HVAC system failure include poor design, undersizing, or lack of routine maintenance. In addition to indoor air quality, the other indoor environmental factors that most influence occupant health and welfare are the thermal condition and the lighting of a facility. HVAC systems that are undersized or not properly functioning can affect the temperature and overall comfort of the facility. Winter coats being worn in school buildings throughout the summer are a common site in facilities with poor ventilation.
Lighting also plays an important role in the ability of students to work efficiently.
Well-lit classrooms contribute to the teachers' ability to present information in a way that can be clearly seen and understood by students. The High Costs of a Poor Indoor Environment Poor indoor air and environmental quality can have many negative effects on students, teachers and other staff. These effects all translate into high costs for the school administration. The expense and effort required to prevent most indoor air quality problems is much less than the expense and effort required to solve problems after they develop. A Profitable Solution Increasing a school's energy efficiency is an effective way to prevent or solve many indoor air and environmental quality problems.