We have compiled key information to help you make decisions. Scroll through the page or navigate to the topic of interest to you:

Wildfires and impact on air quality 

Wildfires, like those that burned across Canada and the Western United States during the summer of 2023. can lead to large amounts of smoke that lowers air quality. When wildfires are large, the resulting smoke can be carried by air currents across large distances. If wildfires are not brought under control, air quality can remain poor and even dangerous for weeks or months.

Smoke released from wildfires contains small particles from burnt vegetation. These particulates are the main cause of haze or reduced visibility; these particles also cause health risks.

Small particles, called PM2.5, pose the greatest risk. These particles are four times smaller than dust and pollen or 30 times smaller than the width of an average human hair. PM stands for particulate matter, while 2.5 refers to the size of the particles in microns (represented as µm). 

These small airborne particles are bad for human health because they penetrate deep into lung tissue and enter the circulatory system. Breathing in high levels of PM2.5 increases the risk of heart disease, asthma, and other health problems.

Wildfire smoke also contains larger particulate matter (called PM10); these larger particulates are what irritates the eyes, nose, and throat.  

During wildfire events, exposure to wildfire smoke is an important health consideration. Wildfire smoke-related health risks are measured and reported in terms of air quality, measured by detection of levels of PM2.5 in the air. You can see current wildfire-related PM2.5 levels in your area by visiting the FireAirNow Website.

Air Quality levels and what they mean 

The Air Quality Index (AQI) reports daily air quality on a scale of 0 to 500. High AQI values indicate that there is a greater level of air pollution and particulate matter. This means that there is a greater risk to health. Low AQI values indicate that there is a low level of air pollution and particulate matter. This means that there is a lower risk to health.

To help make decisions about health risks, there are six AQI categories that correspond to colors. For each AQI category, there are actions that you can take to protect yourself and others. The following guidance is adapted from two reliable sources: Airnow AQI Basics and NYS AQI Basics. 

An AQI reading of over 100 is considered “unhealthy”, a reading over 200 is considered “very unhealthy”, and a reading of over 300 is considered “hazardous”. For sensitive, at-risk groups, health effects may occur at lower AQI readings.

When you need to make a community decision related to wildfire smoke air quality, follow these three steps.

1. Access reliable information.

For reliable reporting on current air quality in New York State visit:

• • The EPA’s https://fire.airnow.gov/
  • New York State’s Air Quality Forecast: https://dec.ny.gov/environmental-protection/air-quality/air-quality-index-forecast-current-observations

2. Understand what the data are reporting.

There are a number of ways that wildfire smoke air quality might be reported. Check to see if the data are 24-hour AQI or Nowcast AQI (current reading). If the data does not say Nowcast, it is likely a 24-hour average. Remember that….

• • 24-hour averages may not reflect current conditions. This is a picture of the past. Air quality could be getting better or worse.
  • Air quality data does not predict future air quality, unless it specifically reports being forecasted data.
  • Even if you are reading forecast data, air quality can change quickly. Stay aware.

3. Check to see trends.

Something that can help your decision-making is asking: is the air quality getting worse or better? If things have been getting worse over the last number of hours, then you might presume that air quality will be poor for a while. If things have been getting better, you might see that as a sign that risks will lower. To check trends:

• • • Visit the EPA’s https://fire.airnow.gov/
  • Select one of the monitors (circles) or sensors (squares) on the map to see detailed information
  • Click on the “trend” icon to see details

For more detailed information on how to interpret wildfire smoke data, visit the Acting on AQI Data and Interpreting Wildfire Smoke Data pages.

How wildfire smoke and air quality levels affect health

Exposure to wildfire smoke affects people’s health. Exposure to particulate matter irritates the eyes, nose, and throat, and increases the risk of heart disease, asthma, and other health problems. When AQI readings are high, the risk of exposure to harmful particles increases.

Particle pollution from wildfire smoke can cause a range of symptoms and health effects.

• Symptoms similar to allergies
  • Red eyes
  • Respiratory symptoms such as coughing, wheezing, difficulty breathing, excess phlegm

• More severe symptoms (with extended exposure)
  • Bronchitis
  • Reduced lung function
  • Worsening asthma
  • Increased rates visits to emergency room
  • Increased rates of hospital admissions
  • Cardiovascular effects leading to heart failure, stroke

There is growing scientific evidence to link cardiovascular and respiratory effects to wildfire smoke exposure.  Exposure to particle pollution can exacerbate existing diseases, create pulmonary inflammation, and cause reductions in lung function.

When planning for or responding to a wildfire smoke event, there are priority groups that are at more risk of health effects. The Environmental Protection Agency (EPA) has published a list of at risk populations, including those with asthma or respiratory diseases, those with cardiovascular disease, children, pregnant people, older adults, those who work outdoors, and those of lower socio-economic status.

For more detail about planning wildfire smoke exposure interventions that protect priority at-risk populations, please refer to our Priority Populations webpage.

Equity Considerations

As a decision maker, there are likely some situations that seem like there’s no perfect answer: how do I protect the majority of the population, while also recognizing that there will be challenges for some. This is the public health paradox. 

We have presented five case studies to help you to consider pros and cons:

• Families and Children
• Workers
• Older Adults
• People with Low Incomes
• People Experiencing Homelessness or Living in Substandard Housing

In addition to reaching all people in a community, it is important to provide translated materials and non-written (e.g., verbal or video) communications. This can expand the reach of information and reduce confusion and misunderstandings, improving knowledge of wildfire smoke health effects and of the steps to take to minimize exposure risk. 

For a list of resources in different languages, refer to the Resources in Non-English Language page. For a list of non-written communications, refer to the Videos and Infographics page. 

Educational materials, information on air quality, and recommendations to protect health should come from trusted sources in the community, including local organizations such as community centers, schools, churches, and public officials. Working with trusted sources can improve the acceptance of information within the community, benefiting overall community health during wildfire smoke events.

If you are considering how to mitigate risks for the community, please refer to the Community Risks page. The page includes information on risk mitigation in cleaner air spaces, schools and daycares, employers and workplaces, senior homes, and hospitals.

How to protect you and your staff outside

Regularly monitor wildfire and air quality data from Fire.AirNow.gov. Refer to both the daily AQI and the extended forecast AQI.

When air quality is poor, the best strategy to protect your and others’ health is to limit time spent outdoors. If it looks or smells smoky outside, it is best to avoid outdoor activities, especially strenuous activities such as exercise that increase the amount of smoke that is inhaled. Air quality can be poor even if you don’t see or smell smoke, so it is important to continue to monitor the AQI.

• When the AQI is >151, consider relocating work to areas with safer air quality or to indoor areas with air filtration; reducing the intensity of outdoor work to moderate or light levels; and providing N95 respirators to outdoor workers.
• When the AQI is >301, it is strongly advised to relocate outdoor work to areas with safer air quality and to indoor areas with air filtration; reduce the intensity of outdoor and indoor work to light level; and provide N95 respirators to all workers. Consider remote work options if possible.

If you must do outdoor activities, try to plan them for days and times when air quality is better.

How to protect you and your staff indoors

Staying indoors may reduce exposure to wildfire smoke. However, PM2.5 can enter buildings through ventilation systems, open doors and windows, or through small cracks and gaps in a building’s structure.

Before a wildfire event occurs, it is beneficial to have a safe indoor environment if air quality becomes poor. Potential steps to take include:

• • Having indoor HEPA air filters available for buildings – either purchased or homemade
  • Ensuring access to an indoor space at your office with an HVAC system with advanced filtration
  • Consider installing indoor air quality monitors to measure indoor PM2.5 levels. To understand how to select, use, and interpret data from indoor PM2.5 sensors, refer to:
    • U.S. EPA, Low-Cost Air Pollution Monitors and Indoor Air Quality
  • For more information on indoor spaces and wildfire smoke, visit the EPA website on the topic

For more information of protecting indoor air quality, refer to the Indoor Air Quality Risks page.