{"id":10040,"date":"2025-09-11T17:59:10","date_gmt":"2025-09-11T17:59:10","guid":{"rendered":"https:\/\/www.newsbeep.com\/il\/10040\/"},"modified":"2025-09-11T17:59:10","modified_gmt":"2025-09-11T17:59:10","slug":"how-to-tell-if-your-outdoor-air-is-safe","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/il\/10040\/","title":{"rendered":"How to Tell If Your Outdoor Air Is Safe"},"content":{"rendered":"

When George Thurston leaves his cottage in the woods of Waccabuc, N.Y., to head for work, a pollution monitor clipped to his belt\u2014called an AirBeam<\/a>\u2014shows pristine air quality. As he takes the train through the suburbs, the device\u2019s digits rise, meaning more pollution. By the time he gets to his office in Manhattan, they\u2019re even higher.<\/p>\n

\u201cIt\u2019s important to know your exposure profile to protect against everyday cumulative risk,\u201d says Thurston, professor of medicine and population health at NYU\u2019s School of Medicine.<\/p>\n

Compared to other toxins in the environment like plasticizers and pesticides, outdoor air pollution is the most harmful type based on current evidence causing millions of deaths per year<\/a>. Using an air quality index (AQI) is one way to tell how polluted the air you\u2019re breathing is. Many AQIs\u2014from the readouts on Thurston\u2019s gadget to ones based on gold-standard detection stations built by the U.S. Environmental Protection Agency\u2014have been developed to monitor pollution and inform you when being outside is safe.<\/p>\n

But their assessments and forecasts often conflict. \u201cThe different data streams have their own biases and assumptions,\u201d says Makoto Kelp, assistant professor of atmospheric sciences at the University of Utah. \u201cI don\u2019t think they\u2019re very well communicated to the public.\u201d<\/p>\n

With harmful particles in the air partly due to intensifying wildfires<\/a>, here\u2019s how to figure out your personal risk for outdoor air pollution to protect your health.<\/p>\n

Why your air quality matters<\/p>\n

Death certificates list causes like heart disease<\/a>, stroke<\/a>, and cancer<\/a>, but these diseases have their own causes. They\u2019re shaped by underlying forces, including air pollution in many cases<\/a>.\u00a0<\/p>\n

Pollution isn\u2019t just one thing; it\u2019s a mix of toxins from vehicle emissions, coal-fueled power plants, and natural gas used to heat buildings. Such substances contain dangerous material called particulate matter 2.5. Much thinner than a strand of hair, PM2.5 can penetrate deep inside the body, where it drives many<\/a> of pollution\u2019s health impacts. <\/p>\n

Read More: Weighted Vests Are the Latest Fitness Trend. Do They Work?<\/a><\/p>\n

Take dementia<\/a>. \u201cEvery reduction in pollution matters,\u201d says Haneen Khreis, senior research associate at Cambridge University. Earlier this year, her team studied long-term exposure and found<\/a> that, with every 10 micrograms of PM2.5 (per cubic meter of air) we\u2019re exposed to, dementia risk increases by 17%. (For perspective, 10 micrograms of PM2.5 is the average roadside measure<\/a> in central London.)<\/p>\n

If you already have a chronic disease, \u201cpoor air quality may make it worse,\u201d Khreis explains. According to Thurston\u2019s research<\/a>, the month after a Pittsburgh plant stopped emitting fossil fuels, emergency hospital visits for pediatric asthma dropped by 41%\u2014and continued declining after that.<\/p>\n

The trouble with tracking pollution<\/p>\n

We can protect ourselves from pollution only if we know it\u2019s there. AQIs focus on tracking and forecasting the most widespread pollutants: PM and ozone.\u00a0<\/p>\n

The EPA posts its AQI on AirNow<\/a>. Other AQIs are provided by weather apps like AccuWeather<\/a> and companies like PurpleAir<\/a> that share readouts from their networks of privately owned sensors.\u00a0<\/p>\n

These AQI values frequently diverge because each organization compiles its own data before converting their findings (with the EPA\u2019s formula) into a 0-500 risk score. There\u2019s no consensus on which data to use partly because the science of monitoring and predicting air quality is so complex. \u201cThere\u2019s more randomness and uncertainty, compared to weather forecasts,\u201d Kelp says.<\/p>\n

AQI forecasts are easily scuttled by the wind<\/a>. Both its speed and direction can change on a dime. Pollution tends to travel with moving weather masses, says Jonathan Porter, chief meteorologist at AccuWeather, a company that tracks and forecasts weather including air pollution. If the wind shifts from polluted areas nearby, the unhealthy air could quickly blow into your area. Or your AQI could improve if the wind picks up in the lower atmosphere, suddenly dispersing stagnant, pollutant-filled air.\u00a0<\/p>\n

AQIs may also lag behind unforeseen temperature changes<\/a>. Strong sunlight can worsen air quality by driving chemical reactions like ozone formation.<\/p>\n

Another complication: it\u2019s hard to calculate mixtures of pollutants in the air, so AQIs focus on whichever pollutant is currently highest\u2014more of a sketch than a full portrait. Researchers have found<\/a> that the EPA\u2019s daily AQI was less reliable for predicting health problems during warmer weather months, when pollutants mix more.\u00a0<\/p>\n

The most accurate air-pollution detectors<\/p>\n

EPA\u2019s stations are the most accurate detectors. The agency\u2019s site, AirNow, uses these readouts<\/a> to calculate current AQI. AirNow also predicts next-day AQI by analyzing recent data with sophisticated forecasting algorithms.<\/p>\n

Through AirNow, you can learn about regional pollution events<\/a> like wildfire smoke affecting nearly everyone\u2019s air in wide areas around the monitoring stations. But there aren\u2019t enough of these stations because they\u2019re expensive to build and run. A consequence is that on days without a broadly impacting event\u2014when air quality in a given location is shaped more by local factors like traffic\u2014these monitors can\u2019t tell you as much about many places\u2019 local pollution levels. \u201cMonitors are often lacking in areas that are less populated or have only recently become more populated,\u201d says Loretta Mickley, senior research fellow in chemistry at Harvard University.<\/p>\n

Read More: Can Creatine Keep Your Brain Sharp?<\/a><\/p>\n

PurpleAir\u2019s AQI helps inform you about local pollution. Its online map displays readouts from people\u2019s at-home sensors, better reflecting if a nearby traffic jam or mail truck<\/a> is spiking fumes, a neighbor starts burning trash, or a local factory releases a smoke plume.\u00a0<\/p>\n

\u201cYou can\u2019t predict when these things will happen,\u201d says Adrian Dybwad, PurpleAir\u2019s CEO. \u201cIf your kid has asthma, you want real-time, real-close information.\u201d The EPA is piloting ways to combine<\/a> its official sensors with PurpleAir data.<\/p>\n

PurpleAir can be \u201creally useful,\u201d Kelp says, though his research shows its crowdsourced networks rarely include<\/a> lower-income communities. He also notes the at-home sensors sold by PurpleAir, ranging from $139 to $299<\/a>, are lower quality than the EPA\u2019s stations\u2014and they become less accurate when misplaced or degrading over time. \u201cThere are no standards for installing or maintaining them,\u201d he says.\u00a0<\/p>\n

PurpleAir doesn\u2019t forecast pollution, while AccuWeather tries to predict AQI hourly throughout the day for towns or cities based on available data informing their models. \u201cWe focus on quality control as we integrate the latest observations as quickly as possible,\u201d Porter explains. AI plays a role; Porter says AccuWeather\u2019s machine learning algorithms compute 70 billion data points each hour.<\/p>\n

A lack of standardization<\/p>\n

Another issue is that AQIs use different color codes and thresholds for when the air is bad enough to trigger health problems in a single day. AirNow flags air quality as unhealthy\u2014color-coded orange\u2014whenever PM2.5 levels rise above 35.5 micrograms.\u00a0<\/p>\n

But the WHO\u2019s guidance is more stringent, recommending a maximum of 15 micrograms. AccuWeather\u2019s scale tracks to the WHO standard<\/a>. This explains why AccuWeather\u2019s AQI might indicate pollution is \u201cfair\u201d when AirNow shows it\u2019s \u201cgood.\u201d PurpleAir lets you choose filters that apply either the EPA\u2019s or WHO\u2019s standards. <\/p>\n

Read More: Your Quest for Perfect Sleep Is Keeping You Awake<\/a><\/p>\n

Mickley generally follows the EPA guidance. \u201cI will exercise outside in moderate yellow conditions,\u201d she says. \u201cWhen it turns orange, I stay inside.\u201d<\/p>\n

Thurston thinks color-coded schemes should eliminate green to avoid implying completely safe air, since even the lowest pollution levels<\/a> compromise health with long-term exposure. For the average concentration of PM2.5 you breathe throughout a given year, lower cutoff points have been established by both the EPA (9 micrograms) and WHO (5 micrograms). This means if your average exposure is regularly above these levels over the long-term, risks for chronic diseases may rise.<\/p>\n

How to use air-quality readings in your everyday life<\/p>\n

So how should people use all of these different AQIs? \u201cThe best approach is to combine them,\u201d Kelp says.\u00a0<\/p>\n

Here\u2019s a five-step plan:<\/p>\n

Sign up for AirNow emails<\/p>\n

AirNow is the go-to place to learn about regional events significantly driving up pollution. Sign up for its daily emails<\/a>, called EnviroFlash, to stay informed. For instance, if a wildfire\u2014even if far away\u2014coincides with weather systems blowing pollution into your region, AirNow\u2019s email will recommend staying indoors more than usual.<\/p>\n

Follow a local sensor <\/p>\n

Before exercising or spending much of the day outside, check the air quality by looking at PurpleAir\u2019s map<\/a> displaying local sensors, wherever people own and deploy them. Another similar site, like IQAir<\/a>, might draw from a sensor that\u2019s closer to you.\u00a0<\/p>\n

You could also get your own personal monitor\u2014many are affordable, and though their accuracy is limited, \u201cthey\u2019re good for showing overall trends,\u201d Kelp says.\u00a0<\/p>\n

Observe your environment<\/p>\n

Learn to recognize generalities and patterns in your environment that, more often than not, track with pollution. Combined with AQIs, they should inform your overall assessment and actions.\u00a0<\/p>\n

For example, Thurston realized pollution is usually higher on the subway<\/a>, so he wears a mask when riding it.<\/p>\n

Read More: You Should Be Washing Your Shoes. Experts Explain How<\/a><\/p>\n

Khreis knew from research that living by a busy road increased<\/a> her exposure \u201cexponentially\u201d compared to about 1 mile from the road, even though the available AQIs didn\u2019t reflect this problem. She moved to a home farther away.\u00a0<\/p>\n

She also bikes in areas with less traffic and more greenery. Trees may help<\/a> disperse pollution. Results depend on several factors like tree species, but \u201coverall I think they help,\u201d Khreis says.<\/p>\n

Other patterns are weather-related<\/a>:<\/p>\n

Sunny summer afternoons often coincide with pollution, which then drops in the evenings.\u00a0The reverse may be true in winter: higher AQIs occur in the morning as people wake up and turn up their heating units.Rain droplets may wash away<\/a> pollutants.\u00a0\u00a0<\/p>\n

Avoid exercising outside when worse air is likely based on these patterns, or at least check your AQI app beforehand to help ensure pollution isn\u2019t excessively high.<\/p>\n

Check hourly forecasts<\/p>\n

If you\u2019re about to go outside for a long time, consult AccuWeather\u2019s hour-by-hour forecast. Just don\u2019t over-rely on its accuracy, since it may shift while you\u2019re out. \u201cWe always recommend people check back with us to stay updated,\u201d Porter says.\u00a0<\/p>\n

Local monitors can help point you to real-time changes.\u00a0<\/p>\n

Aim for mostly good air<\/p>\n

Try to limit your average exposure on most days.\u00a0<\/p>\n

Cumulative long-term exposure to low-level pollution may cause more chronic disease<\/a> than peak pollution events. So if you\u2019re outside for a while on a day with high AQI, it helps significantly to drop your average by reducing exposure when indoors<\/a>. Consider getting indoor air purifiers<\/a>\u2014for your house and car<\/a>\u2014and an electric stove<\/a> instead of a gas one, which emits<\/a> a carcinogen called benzene.\u00a0<\/p>\n

The air outside is often beyond your control, but people spend only 10%<\/a> of their time there. Cleaning up your own indoor air could be a life-saver.<\/p>\n","protected":false},"excerpt":{"rendered":"When George Thurston leaves his cottage in the woods of Waccabuc, N.Y., to head for work, a pollution…\n","protected":false},"author":2,"featured_media":10041,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[242,2663,9884,85,46,141,558],"class_list":{"0":"post-10040","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-environment","8":"tag-environment","9":"tag-evergreen","10":"tag-freelance","11":"tag-il","12":"tag-israel","13":"tag-science","14":"tag-wellness"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/10040","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=10040"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/10040\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/10041"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=10040"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=10040"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=10040"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}