Indoor Air Quality Protections

Woman sitting on couch

ENERGY STAR certified homes and apartments can help provide cleaner air to breathe and reduce exposure to airborne pollutants and contaminants, including many protections against seasonal outdoor allergens and common asthma triggers.  Although there is no cure for asthma, asthma triggers can be controlled in part through the management of the indoor environment.

Seasonal Allergies/Outdoor Asthma Triggers

Seasonal allergens and outdoor air pollution can adversely affect indoor air quality.  When outdoor air is unhealthy to breathe, local officials may advise you to stay indoors.  However, some of the pollutants from outdoors can enter the home and reduce indoor air quality through leaks in the building envelope.

EPA's ENERGY STAR program includes numerous prescriptive air sealing requirements, which reduce the transfer of outdoor air pollutants into the home.  Filters on the ducted heating and cooling system can further reduce the number of particles in the indoor air.


Pests can be a vector for disease and bring undesirable pathogens into homes.  Droppings or body parts of cockroaches and other pests can trigger or worsen asthma symptoms.  Certain proteins are found in cockroach feces and saliva that can cause allergic reactions or trigger asthma symptoms in some individuals.

Homes and apartments that earn the ENERGY STAR label minimize pathways available for pests to enter the home by sealing penetrations.

Pet Allergens and Other Particle Pollution

Residue from pests, such as rodents and cockroaches, can trigger allergy and asthma attacks.

Pet allergens, such as proteins in pet dander, urine, feces, saliva, and hair, can trigger or worsen asthma symptoms.  Particle pollution (also known as particulate matter) from cooking, candles, fireplaces, cigarette smoking, and various outdoor sources can aggravate the lungs and lead to a number of health effects, including asthma symptoms.

Cooking is a major source of indoor particulate matter.  Vented kitchen range hoods over cooktops and stoves help exhaust air directly outside and reduce the concentration of particulates from cooking.

All ENERGY STAR certified homes and apartments include properly designed HVAC systems with minimum MERV 6 filters to help remove these and other indoor air contaminants that are carried on small particles and are potential asthma triggers.

Molds and Humidity

Moisture can lead to mold and other biological pollutants that can cause health problems. Mold spores are naturally present in indoor air, and when they land on damp surfaces in a home, they may begin growing. Molds can grow almost anywhere when moisture is present.  For people sensitive to mold, inhaling mold spores can trigger or worsen asthma symptoms.

It is important to keep the indoor air dry enough to help prevent the growth of mold.  If indoor air is too humid, moisture can condense on surfaces and enhance the growth of mold. Potential health effects and symptoms associated with mold exposure include allergic reactions, asthma, and other respiratory complaints. The moisture in an ENERGY STAR certified home or apartment is carefully controlled, both mechanically and by the tightness of the home, to reduce mold growth and maintain a healthier level of humidity.

ENERGY STAR certified homes and apartments have additional construction features, including improved roof, wall, and foundation drainage to keep water where it belongs—outside of the home.

Carbon Monoxide

Carbon monoxide (CO) is an odorless, colorless, and toxic gas.  Because it is impossible to see, taste, or smell the toxic fumes, CO can kill you before you are aware it is in your home.  At low levels of exposure, CO can cause fatigue in healthy people and chest pain in people with heart disease when at low levels.  At higher concentrations, health effects include impaired vision and coordination; headaches; dizziness; confusion; nausea.  CO exposure is fatal at very high concentrations.

When ENERGY STAR certified homes and apartments include combustion appliances such as furnaces and water heaters, those appliances must be directly vented to the outdoors; installed in lower-risk areas, such as garages or attics; or tested for proper operation.  Vented kitchen range hoods help exhaust some of the combustion byproducts from gas ovens and ranges.  Attached garages must be air-sealed to prevent automobile exhaust from entering the living areas.

Nitrogen Dioxide

Nitrogen dioxide (NO2) is an odorless gas that can irritate your eyes, nose, and throat and cause shortness of breath.  NO2 can come from appliances inside your home that burn fuels such as natural gas, kerosene, and wood.  Gas cooktops and ovens are a major contributor to indoor NO2 exposure.  Studies show a connection between breathing elevated short-term NO2 concentrations, increased visits to emergency departments, and hospital admissions for respiratory issues, especially asthma.

When ENERGY STAR certified homes and apartments include combustion appliances such as furnaces, boilers, water heaters, and fireplaces, they must be power-vented or direct-vented; or installed in lower-risk areas such as garages or attics; or tested for proper operation.  Vented kitchen range hoods over cooktops and stoves help exhaust air directly outside and reduce the concentration of any irritants from cooking.

EPA programs that offer additional protections

  • ENERGY STAR NextGen certified homes and apartments further reduce exposure to CO and NO2 due to fewer combustion appliances in the home.  In this advanced program, kitchen ranges are electric, and efficient heat pumps are required for water heating.
  • EPA's Indoor airPLUS program expands on the core protections required by ENERGY STAR to include additional requirements addressing radon, building materials, increased filtration, and more.
  • DOE’s Zero Energy Ready Home program requires projects to certify to both ENERGY STAR and Indoor airPLUS.

Learn more about the key features of ENERGY STAR certified homes that can improve indoor air quality.