Health Effects of Wildfire Smoke

Although there are many hazardous chemicals in wildfire smoke, the main harmful pollutant for people who are not very close to the fire is “particulate matter;” the tiny particles suspended in the air. The smallest, and usually the most harmful, particulate matter is called PM2.5 because it has a diameter of 2.5 micrometers or smaller. Particulate matter can irritate the lungs and cause persistent coughing, phlegm, wheezing or difficulty breathing. Particulate matter can also cause more serious problems, such as reduced lung function, bronchitis, worsening of asthma, heart failure and early death. People over age 65 and who already have heart and lung problems are the most likely to suffer from serious health effects.

Determining Factors for Air Quality

Various government agencies monitor the air at locations throughout California and report the current Air Quality Index (AQI) for those places. The AQI is a measurement of air pollution. An AQI over 100 is unhealthy for sensitive people and an AQI over 150 is unhealthy for everyone. While a value of 150 indicates the need for action, it does not necessarily reflect a threshold for “unsafe” air. Individuals with lung disease, older adults and children may experience symptoms at AQIs closer to 100. Although there are AQIs for several pollutants, California Occupational Health Administration (Cal/OSHA) regulation about wildfire smoke only uses the AQI for PM2.5. The easiest way to find the current and forecasted AQI for PM2.5 is to go to www.AirNow.gov and enter the ZIP code of the place where you will be working.

Cal/OSHA asks that employers use the Environmental Protection Agency (EPA) monitors when making decisions related to their Wildfire Smoke Guidance, which the campus treats as a regulation. Therefore, Stanislaus State utilizes the official EPA monitors because the OSHA regulation on wildfire smoke quotes the need to use the EPA monitors.

The University also owns and operates 12 additional air monitors located on campus which are called PurpleAir. PurpleAir monitors use a slightly different technology than the EPA monitors, and they are in different locations, so they are not exact duplicates of the EPA measurements. The EPA published research on PurpleAir monitors that determined a correction factor that needs to be included in PurpleAir monitors so that they align better with the EPA monitors when wildfire smoke in the air. This PurpleAir system is part of the University’s decision-making procedure but should only be used as a point of reference for trending one way or another.

The AQI provides guidance for people with a sensitivity to smoke and those who work outdoors. The AQI is not to be used as a regulatory number like a permissible exposure limit (PEL), which quantifies exact exposures to workplace hazards in the air. The AQI is a public health advisory number.

University Considerations

Unless the AQI remains/sustains at “=very unhealthy” levels (201-300) for a significant number of consecutive hours, we expect our campus to remain open. We will communicate about any schedule changes for outdoor classes and activities and/or curtailment of any campus operations. Learn more about the AQI’s six health categories.

Office of Strategic Communications & Marketing and the Office of Safety & Risk Management (SRM) are responsible for informing the campus about air quality, protective measures, and campus closures, with consultation provided by the Wildfire Smoke Task Force (WSTF).

The WSTF group is comprised of EOC members; EOC Executive; EOC Manager, Chief of Police, Public Information Officer, Logistics Section Chief, CPFM Director of Facilities Operations, and Human Resources.

Communication methods can include emails, text alerts, and/or Stanislaus State website updates. Employees are encouraged to notify their supervisors of worsening air quality and any adverse symptoms they may be experiencing due to smoke exposure. Supervisors must then relay this information to SRM (209-667-3572) for follow-up.

Safety & Risk Management will notify the campus of poor air quality and will provide the current AQI for PM 2.5; and will provide protective measures available to employees to reduce their exposure to Wildfire smoke.

Depending on the severity of the situation, protective measures may include:

  • Notify the campus community and give regular updates via the emergency notification system and email;
  • Encourage the campus community to stay indoors;
  • Make masks available if employees must work outdoors;
  • Partially or fully close the campus in consultation with health and safety recommendations;
  • Or take other measures as necessary depending on the circumstances of the situation

Employees are to inform their employer if air quality worsens, or they experience any adverse symptoms that may be the result of wildfire smoke exposure such as asthma attacks, difficulty breathing, and chest pain.

Frequently Asked Questions

Unless the AQI remains/sustains at “Very Unhealthy” levels (201-300) for a significant number of consecutive hours, we expect our campus to remain open. We will communicate about any schedule changes for outdoor classes and activities and/or curtailment of any campus operations. Learn more about the AQI’s six health categories.

Unless the AQI remains at “Very Unhealthy” levels (201-300) for a significant number of consecutive hours, we expect our campus to remain open. We will communicate about any schedule changes for outdoor classes and activities and/or curtailment of any campus operations. Learn more about the AQI’s six health categories.

Situation status calls are scheduled and facilitated by the Campus Emergency Manager and include members of the Wildfire Smoke Task Force (WSTF). The WSTF group is comprised of EOC members; EOC Executive; EOC Manager, Chief of Police, Public Information Officer, Logistics Section Chief, and the CPFM Director of Facilities Operations.

Situation Status calls are scheduled on a daily basis for the duration of poor air quality incidents. The agenda for the Situation Status Calls is to review current AQI measurements from a variety of sources, weather forecasts, AQI forecasts, CalFire Incidents, Office of Emergency Services, potential campus impacts and planned actions for the next 24 hours. Recommendations are then provided to the campus President and Cabinet for decisions.

Employees are encouraged to notify their supervisors of worsening air quality and any adverse symptoms they may be experiencing due to smoke exposure. Supervisors must then relay this information to SRM (209-667-3572) for follow-up.

If an individual is having health issues that are suspected to be caused by air quality, they should consult with their physician prior to purchasing and wearing a particle-filtering mask (N95 respirator), and limit the amount of outdoor activity. The University does not provide N95 respirators to students, or to employees who are not required to work outdoors.

Caution/warning statements for N95 Respirator Mask:

  • People with chronic respiratory, cardiac, or other medical conditions that make breathing difficult should check with their healthcare provider before using an N95 respirator.
  • To work as expected, an N95 respirator requires a proper fit to your face.
  • The Centers for Disease Control and Prevention does not generally recommend facemasks and respirators for use in-home or community settings.

Employees should contact their supervisor immediately if they are experiencing any adverse symptoms that may be the result of wildfire smoke exposure such as asthma attacks, difficulty breathing, and chest pain.

This Cal/OSHA standard is only applicable when the current Air Quality Index (AQI) for small particulate matter (PM2.5) exceeds 150 and only covers employees who work outside or in non-filtered buildings and vehicles for more than one hour per shift.

When the current AQI for PM2.5 is over 150, employers must provide their workers with proper respirators for voluntary use. If the AQI is over 500, respirator use is mandatory. Respirators can be an effective way to protect employee health by reducing exposure to wildfire smoke when they are properly selected and worn at work. Respirator use can be beneficial even when the AQI for PM2.5 is less than 150, to provide additional comfort and protection. A respirator should be used properly and kept clean.

See Stanislaus State Respiratory Protection Program appendix E for protection from Wildfire Smoke.

Capital Planning and Facilities Management will monitor indoor air quality systems/HVAC and implement mitigation actions

  • due to wildfire smoke, the fresh air intake for occupied buildings may be reduced to 0%-5%
  • NOTE: This action counters CSU COVID-19 recommendations for increased fresh air intake, but is necessary due to poor outdoor air quality

Increasing ventilation with all or mostly outside air may not always be possible or practical. In such cases, the effective rate of ventilation per person can also be increased by limiting the number of people present in the building in general, or in specific rooms. Administrative practices that encourage remote participation and reduce room occupancy can help reduce risks from SARS CoV-2, the virus that causes COVID-19. See ASHRAE for more information on ventilation rates for different types of buildings and other important engineering controls to manage ventilation, moisture, and temperature in a building.

The University has taken measures in accordance with ASHRAE to enhance COVID-19 Air Quality Safety Measures.

Yes, while individual health and sensitivities may vary, traveling to and from classes is generally safe. The EPA’s Air Quality Guide for Particle Pollution provides activity recommendations that correspond to the various air quality levels. For example, when the Air Quality Index (AQI) is over 150, and in the “Unhealthy” range (151-200), the guide states that sensitive groups (people with heart or lung disease, older adults, and children under the age of 14 should “avoid prolonged or heavy exertion.” Everyone else should “reduce prolonged or heavy exertion.”

The EPA’s AirNow.gov.

Go to the EPA’s AirNow.gov page and type in the ZIP code for the area of concern. Stanislaus State’s ZIP code is 95382.

PurpleAir sensors are an "Internet of things" (IOT) air quality sensor or particulate sensor consisting of a network of elements.

PurpleAir uses PMS5003 and PMS1003 laser particle counters. These sensors count suspended particles in sizes of 0.3, 0.5, 1.0, 2.5, 5.0, and 10um. These particle counts are processed by the sensor using a complex algorithm to calculate the PM1.0, PM2.5, and PM10 mass concentration in ug/m3. PMS5003 and PMS1003 sensors come factory calibrated.

Purple Air Sensors on campus:

Indoor locations

  • MSR Lobby
  • Main Dining Hall
  • Student Center
  • Naraghi Hall of Science 1st Floor
  • Theater

Outdoor locations

  • Naraghi Hall of Science Rooftop
  • Drama
  • Child Development Center
  • Al Brenda Athletic Stadium

There are four key reasons why the maps may look different:

  1. AirNow averages sensor data to an hour (so you can compare it to data from regulatory-grade monitors, which report on an hourly basis);
  2. We apply an EPA correction equation to the sensor data before it is displayed to reduce bias in the readings;
  3. We apply AirNow’s Nowcast, which is the algorithm used to relate hourly air quality data to the Air Quality Index (AQI). The AQI for particle pollution is a 24-hour index; and
  4. As part of our quality assurance work, the AirNow Fire and Smoke Map does not include sensors that are labeled as “indoor” or that appear to be malfunctioning. AirNow identifies potentially malfunctioning sensors based on a comparison of readings from the two fine particle sensors each PurpleAir sensor contains, or from user reports.

RAAN (Real Time Air Advisory Network) is an air quality advisory system that collects raw pollutant level data from multiple air monitoring stations managed by the San Joaquin Valley Air Pollution Control District.

There are two stations in Stanislaus County; Modesto, and one of which is in Turlock, within two miles of the campus. There are three stations in San Joaquin County; City of Stockton, Tracy-Airport, and the City of Manteca. Each station detects and collects pollution level data for three pollutants of concern:

  • PM 10 (Particulate matter between 2.5 and 10 micrometers in size) are larger, coarse particles that come from sources such as crushing and grinding operations, road dust and some agricultural operations. PM 10 will primarily collect or deposit in your upper respiratory mucous membranes (nose/throat).
  • PM 2.5 (Particulate matter 2.5 micrometers in size and smaller) are small, fine particles that come from sources such as vehicle emissions, industrial processes, wood stoves and wildfires. PM 2.5 particles are more capable of reaching deep lung tissue, and therefore, are considered potentially more harmful.
  • Ozone (harmful gas that is usually a problem in Turlock and Stockton during summer months).

RAAN has an air quality advisory charting system called ROAR (Real Time Outdoor Activity Risk) that is primarily used by K-12 schools. It is based purely on ozone and PM 2.5 levels.

AirNow is an advisory system that is managed by the EPA. However, AirNow tracks and reports/maps the AQI (Air Quality Index), which is a calculated number using the raw pollutant level data detected/collected by the same air monitoring stations that feed into RAAN.

AirNow.gov tracks the AQI of the three pollutants of concern. The pollutant with the highest AQI value is what is ultimately reported/mapped by AirNow.gov.

The University follows NCAA, California Collegiate Athletic Association and the PacWest Conference compliance guidelines. Student-athletes are advised to check with their coach or athletic trainer for additional guidance.

Depending on the health of each person, one may experience one or more of the following symptoms when exposed to prolonged poor air quality: irritation of eyes, nose and throat; coughing; shortness of breath; and increased susceptibility to respiratory infections.

Susceptible populations include those with heart and lung diseases, pregnant women, outdoor workers, older adults, and the elderly and children under the age of 14.

If someone is experiencing severe health issues such as an asthma attack, call 9-1-1. The Student Health and Counseling Center are also resources available for students.

A student is not required to disclose that they have health concerns.

If, however, a student is unable to complete the required assignments or attend required class meetings, a faculty member can request a doctor’s note to verify a student’s illness. This is the same procedure that would be used for any medical situation that prevented a student from completing required work on a short-term basis.

In the case of a longer-term medical disability, accommodation should be requested through Disability Resource Services.

Outdoor events should be moved indoors or cancelled when air quality reaches PMI 2.5 indicates 151, or Unhealthy for everyone. Consideration should be given for cancelling or moving indoors when PMI 2.5 is at the Unhealthy for Sensitive Groups (101-150). Please refer to the Air Quality Guide for Particulate Pollution.

Updated: January 12, 2024