Air Quality Index explained

Air Quality Index is scale created by the EPA to measure the quality of the air. The HALO Smart Senor has multiple sensors to determine the quality of the air and provide an accurate AQI rating for indoor air quality.

  • Particulate Matter (1 μm, 2.5 μm, 10 μm)

Covid-19 and other viruses can live in particulates in the air and are the cause of droplet and airborne transmission. When these particulates are inhaled they deposit into the respiratory system and deliver their virus payload. The HALO can measure particulate matter 10 microns or less (PM10), 2.5 microns or less (PM2.5) and 1 micron or less (PM1).

  • Carbon Monoxide (CO)

CO is a colorless, odorless gas that can be harmful when inhaled in large amounts. CO is released when something is burned. The greatest sources of CO to outdoor air are cars, trucks and other vehicles or machinery that burn fossil fuels. A variety of items in your home such as unvented kerosene and gas space heaters, leaking chimneys and furnaces, and gas stoves also release CO and can affect air quality indoors.

  • Nitrogen Dioxide (NO₂)

The major sources of NO₂ are primarily emissions from vehicle exhaust gases, & domestic heating. Long-term exposure to NO₂ may cause a wide spectrum of severe health problems such as hypertension, diabetes, heart and cardiovascular diseases and even death.

Other factors to consider that are measured by the HALO but not included in the AQI:

  • Carbon Dioxide (CO₂)

The measurement of the CO₂ (Carbon Dioxide) concentration provides a measure of what percentage of the air we inhale consists of air that has already been exhaled by other people, this is called the Rebreathed Fraction. An elevated rebreathed fraction equals a greater probability of the spread of infection.

  • Volatile Organic Compounds (VOC)

Volatile Organic Compounds or VOCs, refer to organic chemical compounds that can adversely affect human health. They are emitted as vapors from certain solids or liquids and include a variety of chemicals. VOC is seen often in cleaning supplies, adhesives, paints, and air fresheners.

  • Humidity (RH)

Relative humidity plays an important role in the survival of virus’s in the air as well as how long they remain airborne.

Reference: https://www.epa.gov/criteria-air-pollutants