What is the Air Quality Index?
Anyone who’s suffered a sunburn has likely heard of the UV Index. The rating system tells us when and for how long it’s safe to be in the sun, and is a key tool in helping the general population avoid skin cancer. Perhaps less commonly known is the Air Quality Index (AQI, for short), a system designed to alert us when to dangers we might not be able to see.
Every day, the government provides a snapshot of the air we breathe as we go about our lives—working, playing with our kids, or simply resting next to an open window. Here’s everything you need to know about the AQI and how it protects our health:
What’s Air Quality Index and where did it come from?
The Air Quality Index is a 0-500 scale used by the Environmental Protection Agency (EPA) to report and forecast air pollution. In 1976, the EPA created the Pollution Standards Index in order to create a nationally uniform reporting system for tracking healthy air levels. In 1999, it was renamed the Air Quality Index and revised to reflect the system we use today.
What are the criteria for our AQI?
The U.S. focuses on the concentrations of the five major pollutants monitored by the Federal Clean Air Act: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. The highest measurement of any single pollutant dictates that day’s AQI value, all of which are reported on the color-coded AirNow monitoring system.
What do the colors mean?
AQI is segmented on a 0-500 scale based on pollution and health effects. To level-set: A rating of 100 correlates to the public-health standard of a given pollutant.
Here’s how the scale breaks down:
Does the AQI reach ‘unhealthy’ levels in the U.S.? What happens when it does?
The AQI often reaches the unhealthy “red” level in some parts of the U.S. and, rarely, “very unhealthy” and “hazardous” in areas of Idaho and Alaska. This January, the Pacific Northwest, Idaho, and Montana have all had red-AQI alerts. On those days, officials urge people to stay indoors, filter the air in their homes, and drink a lot of water, which allows the body to better dilute phlegm and dislodge smoke particles.
What could be causing air quality to dip on those areas?
AQI measurements can fluctuate based on season, weather patterns, and climate events. In the winter, for instance, carbon monoxide levels are often high because cold weather can stymie some vehicles’ emission-control systems. Additionally, thermal inversions (when layers of warm air settle above cooler air near the ground) are more frequent in the winter; this phenomenon traps emissions from vehicles and wood-burning and leads to drastic deterioration of air quality. In the summer, sunlight and heat can cause volatile organic compounds and nitrogen oxides to form ozone more rapidly.
Do any U.S. cities have poor air quality year-round?
The five worst offenders for year-round particle pollution and also ozone pollution are all in California, according to the American Lung Association. They include: Los-Angeles-Long Beach, Madera-Fresno, Visalia-Porterville-Hanford, Bakersfield, Modesto-Merced, and Sacramento-Roseville.
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Disclaimers
1Airmega air purifiers have been proven to trap dust, pollen, dander in the air based on KCL(Korea Conformity Laboratories) testing. They have been tested according to the Korea Air Cleaning Association standard (SPS-KACA 002-132:2022 Modified) to measure the 0.01㎛ size of particle removal rate. It was tested on maximum airflow speed in normal room temperature and humidity conditions. The performance may vary in the actual living environment of customers. Tested with Airmega Aim, 50, 100, 150, 160 Tower AP-1216L, Mighty AP-1512HH, MightyS AP-1512HHS, 200M, Icon, IconS, 230, 240, 250, 250S, 250Art, 300, 300S, 350, 400, 400S, 450, ProX
2 Our HEPA filter complies with IEST-RP-CC007 standards at speed level 1 as tested by SGS (Société Générale de Surveillance). SGS's test report only reflects SGS's evaluation of the sample and does not reflect the evaluation of the batch of goods from which the sample was taken. Tested with Airmega 100, 150, 160, Mighty AP-1512HH, MightyS AP-1512HHS, 200M, 230, 240, 250, 250S, 250 Art, 300, 300S, 350, 400, 400S, 450, ProX
3 Tested by KCL(Korea Conformity Laboratories) according to JEM 1467: 2015 condition, the concentration of acetic acid was proven to be reduced up to 99.5% in 60 minutes. Results may vary depending on actual environment. Tested with Airmega 150, Mighty AP-1512HH, 200M
4 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022, showed result of over 99.5% removal rate of common household gases including Ammonia, Acetaldehyde, Acetic acid, Formaldehyde, Toluene, Benzene, Nitrogen dioxide (NO₂), and Sulfur dioxide (SO₂) within 30 minutes. Results may vary in different environments and not all odors or gas particles may be removed. Tested with Airmega MightyS AP-1512HHS, 250S, 300S, 400S, 350, 450
5 Test conducted using Coway Allergen filter media (5×5 cm) placed in a polyethylene bag. The allergen solution and sample were immersed in 2 mL of phosphate buffer (100 ng/mL) prior to the reaction and heat-sealed to specimen size. The reaction was maintained at 4°C for 24 hours. Nichinichi Pharmaceutical Co., Ltd. conducted the test using ELISA to measure allergen concentration. Results may vary in actual product usage environments. Tested with Airmega Mighty AP-1512HH, 200M
6 Removal rates of Ammonia (NH₃) and Hydrogen Sulfide (H₂S) were tested in a 1 m³ chamber under EL608:2023 conditions for 30 minutes. Gas Detector Tubes were used for measurement, and testing was conducted by KCL (Korea Conformity Laboratories). Results may vary in actual product usage environments. Tested with Airmega Mighty AP-1512HH, 200M
7 Reduction rates of Naphthalene, Sulfur Dioxide, and Nitrogen Dioxide were tested using the Airmega Mighty AP-1512HH in 1㎥ chamber, following JEM-1467:2015 standards. Tests were conducted by Intertek. Actual performance may vary depending on the living environment. Tested with Airmega Mighty AP-1512HH, 200M
9 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022. The test was conducted with Methyl mercaptan, Isovaleraldehyde, Isovaleric acid in a 1.0±0.1 m³ chamber with a test time of 60 minutes at (24±4)°C and (46±10)% Relative Humidity. A removal ratio of over 99.5% was achieved. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
10 Tested by the Guangzhou Institute of Microbiology, exposed the filter media to protein solutions for 24 hours under ISO 4333-2022 standard. The results showed strong reduction performance: >99.79% for pollen, >99.60% for dog allergen, >99.90% for cat allergen, and >99.80% for dust mites matter allergen. Actual results may vary depending on room size, airflow, and pollutant levels. Tested with Airmega 350, 450
11 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022. The test was conducted in a 1.0±0.1 m³ chamber for 60 minutes at (24±4)°C and (46±10)% Relative Humidity. A removal ratio of >99.5% was achieved for Formaldehyde and Toluene in 60 minutes. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
12 Tested by Intertek. The evaluation was conducted against designated test materials: Sulfur dioxide, Nitrogen dioxide, and Naphthalene. The test was performed in a sealed 1.0×1.0×1.0 m (1.0 m³) odor chamber at a test room temperature of (23±2)°C (measured between 23.6∼23.9°C) and a test room humidity of (45±5)% R.H. (measured between 40∼48)% Relative Humidity. It met the odor removal rate of ≥99.9% for Sulfur dioxide, Nitrogen dioxide, and Naphthalene. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
