Understanding Air Quality: Reading Pollution Indexes

The Air Quality Index (AQI) is a tool used to communicate the quality of outdoor air and its potential health implications. It is calculated using measurements of particulate matter (PM2.5 and PM10), Ozone (O3), Nitrogen Dioxide (NO2), Sulfur Dioxide (SO2), and Carbon Monoxide (CO) emissions. The AQI is measured on a scale from 0 to 500, with higher values indicating increased levels of air pollution and associated health risks. The AQI is divided into six categories, each represented by a different colour and providing specific health advice. For example, an AQI value of 50 or below indicates good air quality, while a value over 300 represents hazardous air quality. The AQI is updated in real-time, providing accurate and actionable information to help individuals make informed decisions about their health and well-being.

The Air Quality Health Index (AQHI)

The AQHI pays particular attention to people who are sensitive to air pollution and provides them with advice on how to protect their health during air quality levels associated with low, moderate, high, and very high health risks. For instance, children and younger adults, people who are pregnant or living with a chronic illness are at higher risk.

The AQHI values are grouped into health risk categories to help people easily and quickly identify their level of risk. These categories are colour-coded, with each colour corresponding to a range of index values. For example, an AQI value of 50 or below represents good air quality, while an AQI value over 300 represents hazardous air quality. AQI values at or below 100 are generally thought of as satisfactory, while values above 100 indicate unhealthy air quality.

Newspapers, radio, television, and websites report AQI levels year-round. Keeping track of the current air quality information in your area can help you take steps to protect yourself and your family from the harmful effects of air pollution.

How AQI values are calculated

The Air Quality Index (AQI) is a uniform way to report daily air quality conditions. It was developed by the Environmental Protection Agency (EPA) and is used to convey how clean or polluted the air is. The AQI is calculated by converting measured pollutant concentrations to a uniform index based on the health effects associated with a pollutant. The health benchmarks used for calculating the AQI are pollutant-specific and are established by the EPA through the National Ambient Air Quality Standards (NAAQS). The Clean Air Act requires the EPA to review these standards every five years to reflect evolving health effects information. The Air Quality Index is adjusted periodically to reflect these changes.

The AQI is based on the concentrations of six major air pollutants: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, nitrogen dioxide, and two sizes of particulate matter (PM2.5 and PM10). Each pollutant is measured separately, and the overall index is defined as the maximum value of the index. The breakpoints between index values are defined for each pollutant, and different averaging periods are used for different pollutants. An AQI value of 100 generally corresponds to the level of the NAAQS for the pollutant. When AQI values are above 100, air quality is considered unhealthy, first for certain sensitive groups of people, then for everyone as values increase.

The AQI is divided into six categories, each with a specific colour, indicating increasing levels of health concern: Good, Moderate, Unhealthy for Sensitive Groups (USG), Unhealthy, Very Unhealthy, and Hazardous. AQI forecasts depend on temperatures, precipitation, wind, and cloud cover, as weather affects pollution creation and transport from other areas. When the AQI is forecasted to be near or exceed 101, an air quality alert is issued, as current or forecasted conditions can be harmful to those sensitive to air pollution.

How to find your local AQI

To find your local Air Quality Index (AQI), you can use a variety of online tools and applications. Here are some ways to do it:

AirNow.gov

This is a website that provides air quality data for locations in the U.S., Canada, and Mexico. On the website, you can use the interactive map to find your location and view the current AQI. The map includes data for air quality monitors in the supported countries. You can also use the search box to search for a specific U.S. location. Additionally, AirNow offers a mobile app, EnviroFlash emails, web cameras, and custom map widgets to help you access air quality information.

AccuWeather

AccuWeather provides air quality data for various locations, including New York, NY, and Chicago, IL. While the data is obtained from Plume Labs, AccuWeather aims to provide accurate and real-time information, including the current index, forecast, daily, and hourly air quality data. You can access this information through their website or mobile app.

Air Quality and Pollution Websites

There are websites dedicated to providing air quality information, such as aqicn.org, which offers real-time air pollution data for over 100 countries. For example, if you're in Bend, Oregon, you can download the Air Quality plugin for Chrome or Firefox to get instant access to local air pollution levels. Additionally, you can refer to health advice and resources, such as the AirNow guide to Air Quality and Your Health, or blogs like www.myhealthbeijing.com.

Government and Official Sources

Many governments and official sources provide air quality data and forecasts for their regions. For instance, the U.S. Environmental Protection Agency (EPA) contributes to maintaining, measuring, and providing Air Quality information to citizens. You can explore their websites or interactive maps to find specific information for your location.

It's important to note that air quality data may be subject to equipment limitations and fluctuations, so it's always a good idea to refer to multiple sources and follow local advisories for the most accurate and up-to-date information.

What to do when AQI levels are high

The Air Quality Index (AQI) is a system used to warn the public about dangerous levels of air pollution. It measures the density of five pollutants in the air: ground-level ozone, particulates, carbon monoxide, nitrogen dioxide, and sulfur dioxide. The AQI is divided into six colour-coded categories, with each category representing a different level of health concern. An AQI value of 50 or below represents good air quality, while a value over 300 indicates hazardous air quality.

When AQI levels are high, there are several actions you can take to protect your health:

• Stay indoors as much as possible, especially if you belong to a sensitive group, such as children, the elderly, pregnant women, or individuals with respiratory or cardiovascular conditions.
• If you need to go outside, consider wearing a well-fitted and certified face mask to reduce your exposure to harmful pollutants. N95, P100, and KN95 masks are effective options.
• Keep indoor air as clean as possible by avoiding activities that can release additional pollutants, such as smoking, burning candles, or using gas stoves. Open windows when outdoor air quality is better to improve ventilation and reduce indoor pollutant levels.
• Invest in an air purifier with a High-Efficiency Particulate Air (HEPA) filter to remove particulate matter and improve indoor air quality.
• Monitor the AQI regularly to make informed decisions about your activities. Stay informed through local radio, TV, newspapers, or mobile apps that provide real-time AQI updates.
• If you start experiencing any adverse health effects, such as coughing, shortness of breath, or irritation of the eyes, nose, or throat, seek medical attention.

It is important to note that even if you consider yourself healthy, high levels of air pollution can still pose a risk to your health. Taking proactive measures to reduce your exposure and protect your respiratory health is crucial when AQI levels are high.

How to improve air quality

The Air Quality Index (AQI) is a system used to warn the public about dangerous levels of air pollution. The AQI is based on measurements of particulate matter (PM2.5 and PM10), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO) emissions. The AQI is divided into six color-coded categories, with each category representing a range of index values. An AQI value of 50 or below represents good air quality, while an AQI value over 300 indicates hazardous air quality.

Reduce Vehicle Emissions

• Drive less: Opt for carpooling, bicycling, public transportation, or walking whenever possible.
• Reduce gas consumption: Plan ahead and combine errands to reduce the number of miles driven.
• Choose efficient vehicles: When purchasing a new car, consider fuel efficiency and choose models that provide the best gas mileage.
• Maintain your vehicle: Regularly service your car and pay attention to warning lights, especially those related to emissions control systems.
• Refuel during cooler hours: In the summer, refuel your vehicle in the early morning or late at night to reduce emissions during high-temperature periods.
• Avoid idling: Turn off your engine when parked to reduce emissions and save gas.

Improve Indoor Air Quality

• Eliminate pollution sources: Identify and eliminate or reduce emissions from individual sources, such as asbestos or gas stoves.
• Increase ventilation: Open windows and doors, use fans, or operate air conditioning with the vent control open to increase the outdoor ventilation rate and dilute indoor pollutants.
• Mechanical ventilation: Consider installing energy-efficient heat recovery ventilators or advanced HVAC systems that bring in fresh outdoor air and improve indoor air quality.
• Cook and heat cleanly: Avoid burning coal, biomass, or wood for cooking or heating, as these contribute to household and outdoor air pollution. Opt for cleaner energy sources and well-ventilated spaces.

Manage Waste and Energy Consumption

• Minimize waste emissions: Compost food and garden waste, recycle non-organic trash, reuse grocery bags, and properly dispose of remaining waste through local collection services.
• Conserve energy: Turn off lights and electronics when not in use to reduce energy consumption and associated emissions.
• Avoid open burning: Never burn trash, as it releases dangerous pollutants and toxic emissions that are harmful to human health, especially for children and older adults.

Support Policy Changes and Stay Informed

• Advocate for stronger emissions standards: Call on local leaders to adopt national air quality standards that align with WHO guidelines and support policies that incentivize the purchase of cleaner vehicles, low-energy appliances, and energy-efficient housing.
• Monitor air quality: Stay informed about local air pollution levels and follow guidance from authorities to limit outdoor activities or avoid hotspots with elevated pollution levels.
• Time outdoor activities: Plan outdoor activities to avoid peak pollution times, such as rush hour traffic, to minimize exposure to high pollution levels.
• Protect yourself: Be aware of your risk factors and use effective protection, such as face masks with strong filters, when advised by local authorities.

Frequently asked questions