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Wildfire smoke and workplace air quality

Last updated on September 14, 2026

Wildfire smoke can affect air quality in indoor and outdoor workplaces and increase risks to employee health and safety. People leaders and employees can take steps to monitor air quality, reduce exposure and protect themselves during wildfire smoke events.

Use this page to understand the health effects of wildfire smoke, identify people who may be at greater risk, monitor workplace conditions and take measures to reduce exposure. For the purposes of this page, people leaders include supervisors and managers responsible for employees working indoors or outdoors.

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Wildfire smoke events

Wildfire smoke events are becoming more common in B.C. Climate change is creating conditions for more frequent and longer wildfires. Wildfires usually occur during the summer, although the wildfire season is becoming longer, with events now happening from spring to fall.

Wildfires produce dense smoke that can travel long distances from the fire. A wildfire does not have to be in your region for your workplace or community to be affected by smoke.

Wildfire conditions are difficult to predict. This includes when wildfires may occur, how large an area they may cover, the amount of smoke generated and the distance the smoke may travel.

Composition of wildfire smoke

Wildfire smoke is a complex mixture of particles, gases and vapour containing hundreds of chemicals. It contains large amounts of particulate matter and gases, including sulphur dioxide, nitrogen dioxide and carbon monoxide.

The composition of wildfire smoke depends on:

  • What is burning
  • The temperature of the fire
  • Wind and weather conditions

Very fine particulate matter, known as PM2.5, is not visible to the human eye. These particles are a health concern because they can reach deep into the lungs and enter the bloodstream.

Health effects of wildfire smoke

Wildfire smoke can have a range of health effects. Inhaling fine particles from smoke can aggravate respiratory and other chronic conditions and contribute to longer-term health problems.

Smoke generated may be a mild to severe irritant. For some people, exposure can be life-threatening. The potential health effects depend on:

  • Amount and duration of exposure
  • Age
  • Personal susceptibility
  • Other factors

Exposure to wildfire smoke affects people differently.

Hot weather can occur at the same time as wildfires and can lead to serious health concerns, including heat stress and heat exhaustion. It is important to stay cool and sufficiently hydrated. For information about managing heat in the workplace, refer to:

People at greater risk

During wildfire conditions that produce heavy air pollution, everyone may be at risk, regardless of age or health. When wildfire smoke affects air quality in an area, people leaders and employees should take appropriate measures to avoid or reduce exposure as much as possible.

Exposure to air pollution from wildfire smoke may irritate the lungs, cause inflammation and affect the body’s immune response.

Some people may be at greater risk of health problems when exposed to wildfire smoke, including:

  • Infants and young children
  • Pregnant people
  • Seniors
  • People who smoke
  • People working or participating in recreational activities outdoors
  • People with chronic health conditions, such as:
    • Asthma
    • Chronic obstructive pulmonary disease
    • Diabetes
    • Heart disease

​Symptoms of exposure to wildfire smoke

Breathing wildfire smoke can cause:

  • Eye, nose and throat irritation
  • Headaches
  • Worsening allergies

Some people, particularly those at greater risk, may experience more serious symptoms, including:

  • Shortness of breath
  • Severe coughing
  • Wheezing
  • Chest pain

Employees should seek prompt medical attention if they experience serious symptoms.

Monitor wildfire smoke and air quality

Wildfire smoke conditions can change quickly. People leaders should check current conditions and forecasts when wildfire smoke may affect employees or workplace air quality.

Check current conditions and forecasts

Use the following sources to monitor current air quality alerts and forecasted air quality:

Review available information regularly because air quality can vary by location and change throughout the day.

Reduce exposure to wildfire smoke

Measures to reduce exposure to wildfire smoke depend on workplace conditions, whether employees are working indoors or outdoors and whether additional protective measures are needed.

Working indoors

Indoor air quality (IAQ) in buildings with mechanical ventilation is cleaner than outside air and better than many homes in B.C. that have little to no mechanical ventilation and rely on outside air for venting and cooling.

Employees must have access to clean air. Clean indoor airspaces are the most effective means to reduce exposure to wildfire smoke. Most BC Public Service workplaces have mechanical ventilation (HVAC) that is operated to industry standards, including WorkSafeBC and American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE). If air quality advisories are in effect, facilities managers increase their monitoring of HVAC systems and make any necessary changes.

Effective filtration is the primary defense for building occupants from air drawn into a building through the HVAC system. Air handling units trap outside particulate in their filters, reducing the amount of particulate that can travel indoors. Each HVAC system has a design-specified filter for removing bacteria, pollen, soot and other small particulates commonly found in the air.

Reducing infiltration of smoke into buildings is also important to reduce exposure by keeping windows and doors closed as much as possible. For example, if a door is for employee only access, ask employees to reduce their number of trips in and out of the building.

For workplace buildings without mechanical ventilation or air conditioning, contact Workplace Health and Safety via AskMyHR and choose service category Workplace Safety and sub-category Other Issues and Inquiries.

Working outdoors

Employees working outdoors may have greater exposure to wildfire smoke. If employees are working outside during periods of heavy wildfire smoke:

For people leaders, if your employees must undertake strenuous work activity outdoors during periods of heavy wildfire smoke, contact a BCPSA Occupational Safety Specialist for advice using AskMyHR and choose service category Workplace Safety and sub-category Other Issues and Inquiries.

Additional protective measures

Portable air cleaners and filtration

Local smoke conditions can vary greatly, and indoor air quality may also vary between nearby buildings. Before bringing air scrubbers, portable air cleaners or HEPA filters into a workplace, review air quality and workplace conditions.

  • Check current conditions and forecasts and consider whether smoke is expected to improve or worsen
  • Review the local weather forecast for changes in wind or weather that may improve air quality
  • Check the indoor air quality:
    • Is there visible haze inside?
    • Is there particulate matter in the air or on surfaces?
    • Is there only an odour?

The smell of smoke may be noticeable at concentrations much lower than those at which it presents a health risk. 

Masks and respirators

Follow public health advice about being outdoors, limiting physical activity and wearing a mask or respirator.

At lower levels, wildfire smoke is generally experienced as an irritant, and people may smell smoke long before it becomes a health risk. As air quality decreases, however, pollution can present a health risk, particularly for people with respiratory conditions.

Well-fitted respirators, including N95, KN95 and KF94 respirators, provide effective protection from particles in wildfire smoke. Three-layer cloth or disposable masks can offer moderate protection if they fit well.

Breathing while wearing a mask or respirator requires more effort than normal breathing. This may create a health risk for people with certain health conditions. Employees who are unsure about using a mask or respirator should consult their healthcare team. Additional respiratory protection information is available from the BC Centre for Disease Control.

• Visit BC Wildfire Service and download the Android App or iOS App
• BC Centre for Disease Control wildfire smoke
• HealthLinkBC wildfires and your health
• National Collaborating Centre for Environmental Health, including wildfire, smoke and health and public health planning for wildfire smoke
• Health Canada, including wildfire smoke, air quality and your health and guidance for cleaner air spaces during wildfire smoke events
• AQMap.ca for current air quality information

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