Indoor Air Quality

At A&L Heating and Cooling we have plenty of experience in both commercial and residential HVAC systems. It’s very important when designing and maintaining these systems to maintain indoor air quality, especially when the systems become larger and more complex. Call us for more information, and we’ll be happy to stop by and examine your system and look for air quality problems in the design and maintenance of it. Are you concerned that there may be health problems in your building because of the way the HVAC is set up? Call us and we will come and check it out.

Heating, ventilation and air conditioning (HVAC) systems are designed to maintain comfort and maximize indoor air quality. While heating and air conditioning are relatively straightforward, complex ventilation systems determine the quality of the indoor environment. The health problems associated with poor indoor air quality cost billions of dollars each year and reduce productivity. A well-designed, properly maintained ventilation system can help to improve indoor environments.

Indoor air pollution and health issues

Indoor air pollution is caused by the build-up of contaminants coming primarily from inside the building. Common sources of indoor air pollution include biological organisms, building materials and furnishings, cleaning agents, copy machines, and pesticides.

These pollutants can contribute to building-related illnesses that have clearly identifiable causes, such as Legionnaire’s disease. Ventilation systems that are poorly maintained can contribute to Sick Building Syndrome, which has physical symptoms without clearly identifiable causes. Symptoms include dry mucous membranes and eye, nose and throat irritation.

These disorders lead to increased employee sick days and reduced work efficiency. The World Health Organization estimates that 30 percent of new or remodeled buildings have unusually high rates of health complaints. The National Institute for Occupational Safety and Health identifies poor ventilation as an important contributing factor in many sick building cases.

Ventilation system problems and solutions

Ventilation is the process of moving air into and out of buildings. Indoor air quality may deteriorate when one or more of these processes is inadequate. Increasing the supply of outdoor air is the most commonly used method to fix indoor air problems, but a number of system design and operational issues can impact indoor air quality.

Variable airflow: Designs specifying HVAC system operation at reduced or interrupted flow in response to space conditioning needs may impair contaminant removal. Define minimum ventilation rates by air cleanliness and distribution, as well as temperature and humidity.
Vent placement: Air supply vents located near sources of pollution, such as exhaust vents, heavy traffic areas, and trash dumpsters, provide a pathway for contaminants to enter into the ventilation system. Carefully evaluate the location of all air supply vents.
Air distribution: Ensure that registers are not blocked by furniture or equipment and that partitions or other barriers are positioned so they do not restrict airflow. Locate air supply and return air vents at a reasonable distance to ensure balanced air distribution.
Scheduling: Ventilation system scheduling is critical to maintaining good indoor air quality. Schedule ventilation operation based on occupancy levels or operating hours. Demand-controlled ventilation using CO2 sensors can optimize indoor air quality and save energy.

Paying close attention to these system design features and operational practices will help you spot potential sources of indoor air pollution and take steps to eliminate them.

Keep it fresh

As with any critical process, optimizing indoor air quality requires ongoing monitoring and a commitment to continuous improvement. Record keeping is also important. Use the HVAC Checklist from the Centers for Disease Control to document inspection and maintenance activities, as well as any indoor air quality problems and the steps taken to solve them. Stay up-to-date on code changes or revisions to ventilation standards.

To get a free estimate, call us today at (508) 737-5751.