Air Quality Alert: How Long Is Too Long Outside?

Spending time outdoors is enjoyable, but it's important to be mindful of the air quality before stepping out. The Air Quality Index (AQI) is a valuable tool that helps us understand the severity of pollution in the air and make informed decisions about our outdoor activities. The AQI is a rating system that measures and rates several major pollutants, including ground-level ozone, particulate matter, carbon monoxide, nitrogen dioxide, and sulfur dioxide. These pollutants can have harmful effects on our health, especially for sensitive groups such as children, the elderly, and people with respiratory or heart conditions. When the AQI reaches levels considered Unhealthy for Sensitive Groups, these individuals are advised to limit their time outdoors and reduce physical exertion. Even healthy individuals may experience symptoms like coughing, sneezing, or itchy eyes in poor air quality conditions. It is crucial to stay informed about the AQI in your area through websites, apps, or local media outlets, and take the necessary precautions to protect your health when spending time outdoors.

Sensitive groups should limit outdoor activities

When air quality is deemed "unhealthy for sensitive groups", it is recommended that sensitive groups limit outdoor activities. This is typically when the Air Quality Index (AQI) is rated between 101 and 150. At this level, people with heart or lung disease, older adults, children, people with diabetes, and people of lower socioeconomic status are advised to reduce prolonged or heavy physical exertion outdoors. This is because they are more likely to experience health effects such as coughing, chest discomfort, wheezing, shortness of breath, and unusual fatigue.

For those with respiratory diseases, high particle pollution levels can make it difficult to breathe deeply or vigorously, and can exacerbate symptoms. People with heart disease, in particular, may experience serious problems with no warning signs, such as chest pain, palpitations, shortness of breath, or unusual fatigue. Therefore, it is important for those in sensitive groups to limit their time outdoors and reduce the intensity of any outdoor activities when air quality is unhealthy.

Children are another sensitive group that should limit outdoor activities when air quality is poor. While healthy children may not experience serious health effects from short-term exposure to particle pollution, long-term exposure can negatively impact lung function growth. Children are more likely to be exposed to air pollution than adults due to spending more time outdoors and being more active. Therefore, parents should be mindful of air quality forecasts and limit their children's outdoor activities when necessary.

In addition to limiting outdoor activities, sensitive groups can also protect themselves from poor air quality by wearing masks. While cloth or dust masks may not effectively filter out fine particles, well-fitted N95 or KN95 masks can provide better protection. Staying indoors with the windows and doors closed, using air conditioning on the recirculate setting, or using a portable HEPA air cleaner can also help reduce exposure to particle pollution.

Everyone should avoid all physical activity outdoors

When air quality is deemed "unhealthy", it is recommended that everyone should avoid all physical activity outdoors. This is because air pollution can be harmful to anyone, but especially to those who are more vulnerable, such as children, teens, the elderly, people with asthma and other lung diseases, people with diabetes or cardiovascular disease, and pregnant women.

Even if you are generally healthy, spending prolonged periods outdoors when air quality is poor can be detrimental to your health. The negative health effects of pollution are exacerbated by extended exposure and the deep, rapid breathing that comes with exercise. Therefore, it is best to avoid all physical activity outdoors when air quality is unhealthy.

If you must go outdoors, consider wearing a well-fitted N95 or KN95 mask, as these have better filtration capabilities and may offer some protection against particle pollution. It is also advisable to stay away from high-traffic areas, as cars can add significantly to the particulate matter in the air.

It is important to monitor the Air Quality Index (AQI) in your area and adjust your plans accordingly. The AQI is a rating system that measures the severity of pollution in the air on a scale of 0 to 500, with values at or below 100 considered satisfactory for most people. When the AQI exceeds 100, the air quality is deemed unhealthy, and the higher the number, the greater the risk to health.

In summary, when the air quality is unhealthy, it is best to avoid all physical activity outdoors to minimize the potential negative health consequences.

Masks can help protect against air pollution

The length of time you can be outside when air quality is unhealthy depends on several factors, including the severity of the pollution, your health, and whether you are wearing a protective mask.

Air pollution is a serious issue that can have detrimental effects on human health. It has been linked to a range of respiratory and cardiovascular issues, as well as neurological problems. The Air Quality Index (AQI) is used to warn the public when air pollution levels are dangerous. When the AQI is above 100, the air quality is considered unhealthy, and the higher the number, the more harmful the pollution is to human health.

On days when the air quality is unhealthy, it is generally recommended to limit prolonged outdoor exertion, especially for sensitive individuals such as children, active adults, and people with respiratory diseases. In some cases, when the air quality is extremely poor, everyone is advised to stay indoors and avoid all physical activity outdoors.

However, masks can provide some protection against air pollution, allowing you to spend more time outdoors. The effectiveness of masks varies depending on the type:

• N95 and KN95 masks offer the highest degree of protection against air pollution. They combine mechanical and electrostatic filtration, effectively trapping submicron particles. N95 masks have been shown to reduce exposure to wildfire smoke by a significant factor.
• Cloth masks, bandanas, and surgical masks offer limited protection against air pollution due to their loose fit and larger fiber size. However, they can still block 15-30% of particles, so they are better than nothing.

While masks can provide some protection, it is important to note that they should be used in conjunction with other measures to reduce exposure to unhealthy air. This includes limiting time spent outdoors, avoiding outdoor physical activity, and staying away from high-traffic areas.

Keep indoor air healthy

Keeping the air inside your home clean is just as important as protecting yourself from outdoor air pollution. Here are some tips to keep the indoor air healthy:

Remove obvious air pollutants

Move any cleaning supplies, paint, or other chemicals out of your main living area. For example, store them in the garage.

Open ventilation windows

Opening windows and doors is a simple and quick way to improve indoor air quality. However, this may not always be practical due to the weather, humidity, pollution, pollen levels, and other local factors.

Update your thermostat

Opt for a thermostat that can circulate air around your home when you're not using the heating or air conditioning. Some circulating thermostats have a feature that runs the indoor fan for 20 minutes every hour, while others allow the fan to run continuously at a reduced speed for constant airflow.

Run exhaust fans

Running a bathroom or kitchen exhaust fan can help improve indoor air quality by removing stale, humid air from your home.

Maintain humidity levels

Moist air can improve indoor air quality, but too much humidity can have the opposite effect. Aim to maintain an indoor relative humidity level between 30% and 50%. Use a dehumidifier during humid seasons and a humidifier during dry seasons.

Buy a quality air filter

Higher-quality air filters will capture more particles, but they will also clog faster and require more frequent replacement. Change your air filter every 30 days or so, or every six months if you have a larger capacity filter.

Limit scented items

Scented candles, air fresheners, and diffusers can contribute to poor air quality. These products often contain harmful volatile organic compounds (VOCs) such as formaldehyde, benzene, and toluene, which can be hazardous to your health.

Stay informed about air quality

Staying informed about air quality is crucial to protecting yourself and your family from the harmful effects of air pollution. Here are some ways to stay informed and take appropriate actions:

• Check the Air Quality Index (AQI): The AQI is a rating system that indicates the severity of air pollution on a scale from 0 to 500. It measures six common air pollutants, including ground-level ozone (smog) and particulate matter. The AQI is available through various sources, such as newspapers, radio, television, and websites. You can also find AQI forecasts and real-time information on the EPA's AirNow website (AirNow.gov) or the National Weather Service (NWS) website (weather.gov).
• Understand the AQI categories: The AQI is divided into six categories, each associated with a specific colour and health advice. AQI values at or below 100 are generally considered safe for everyone. When the AQI exceeds 100, the air quality is unhealthy, and the risk to health increases as the number gets higher. An AQI over 300 is considered hazardous.
• Take protective measures: On days when the AQI indicates unhealthy air quality, take appropriate actions to minimise your exposure. Reduce the time spent outdoors and limit strenuous activities, especially if you are part of a sensitive group, such as children, active adults, or individuals with respiratory conditions. Consider wearing a well-fitted N95 or KN95 mask when outdoors to protect yourself from particle pollution.
• Listen to weather alerts: Stay tuned to weather alerts and notifications from sources like the NOAA Weather Radio or your preferred weather news station. They provide essential information about air quality alerts and help you make informed decisions about your outdoor activities.
• Minimise personal pollution contributions: During periods of poor air quality, minimise activities that contribute to air pollution. This includes reducing the use of cars, avoiding burning debris or using gas-powered equipment, and limiting the use of items that increase pollution levels.
• Stay informed about wildfires: Wildfires can significantly impact air quality due to the release of particle pollution from smoke. Stay informed about wildfire activity in your area and take extra precautions during wildfire season.

Frequently asked questions