Wildfires pose an ever-growing threat to people and businesses, with an estimated annual cost to the U.S. economy of between $394 and $893 billion. The financial impact has increased in recent years due to wildfires becoming more common and devastating in scale. Facility managers also need to consider the less discussed but equally impactful risks of wildfire smoke, and how to mitigate these risks effectively.
Two of the main risks wildfires pose include the destruction of private and commercial property caused by the fires themselves and the knock-on effects wildfire smoke causes to human health and productivity. Smoke-induced health issues include coughing, wheezing, eye pain and other serious impacts, such as the worsening of underlying respiratory or cardiovascular conditions resulting in short- and long-term illness.
Countering the harmful effects of wildfire smoke requires proactive planning and mitigation, with HVAC optimization and continuous indoor air quality monitoring informing aspects of this approach. Lessons learned from similar events should also form the backbone of any risk management plan. Additionally, to keep people inside a building safe, it is essential to ensure there is clear communication of what to expect and do to manage risk.
Understanding Wildfire Smoke Exposure Risks
Safe indoor air is essential for employees to perform at their best and remain healthy. Wildfire smoke poses a unique challenge to indoor air quality through dangerous increases of particulate matter of 2.5 microns or smaller in diameter (PM2.5). Exposure to high levels of PM2.5 can cause respiratory and cardiovascular health effects, especially for individuals with preexisting conditions like asthma and heart disease. Wildfire smoke also contains volatile and semi-volatile compounds and inorganic gas-phase compounds, many of which can pose significant health risks to people.
While staying indoors should keep people safe from the dangers of high PM2.5, the air inside a building can become dangerous due to smoke seeping through windows, doors and ventilation systems. Wildfire smoke can affect the indoor air quality of buildings hundreds of miles away from the source, so monitoring the air quality index is essential.
Common Indoor Air Quality Misconceptions
The following misconceptions about indoor air quality and HVAC systems can affect risk management during wildfire season.
HVAC Is All You Need: HVAC systems require specific upgrades or modifications to manage smoke effectively. For example, standard filters will not capture the fine particulate matter in wildfire smoke, so installing high-efficiency filters, such as HEPA filters, is necessary to ensure proper air filtration.
Closing Windows Keeps Bad Air Out: Smoke can infiltrate buildings through small gaps and cracks, requiring a more comprehensive approach. Sealing potential entry points and using specialized filtration systems can keep indoor air clean.
Indoor Air Is Always Safe: While indoor environments generally reduce direct exposure to smoke, they can still become hazardous if proper ventilation and filtration measures are not in place. Without continuous monitoring and proactive management, the air quality inside a building can deteriorate quickly, posing health risks to occupants. Therefore, effective filtration, sealing and monitoring strategies should be combined to ensure that indoor air remains safe and healthy during wildfire season.
Reducing the Impact of Wildfire Smoke on Building Occupants
To ensure that employees and building occupants remain safe from harmful wildfire smoke, organizations should take the following actions:
1. Ensure HVAC Systems are Fit for Purpose
When an area is affected by wildfire smoke, to keep indoor air safe and healthy, it is essential to ensure HVAC systems are working properly, check that filters are clean and close dampers when PM2.5 levels rise. If they regularly filter wildfire smoke, HVAC filters can become clogged more quickly and ultimately become less effective. Especially during wildfire season, replacing these filters can help keep systems functioning properly.
2. Establish a Plan for Sealing Buildings and Adjusting Ventilation to Minimize Smoke Entry
Straightforward measures to seal a building can help keep smoke out. For example, keep all interior and exterior windows and doors closed. Additionally, limiting outdoor intake via ventilation systems can stop particles from entering the building. Use recirculation settings in HVAC systems to keep indoor air moving without drawing in contaminated outside air. Ensure that high-efficiency systems are filtering any necessary outdoor air intake.
3. Know Your Building’s Indoor Air Quality Baseline
If you do not know your building’s normal performance, it is extremely difficult to prepare the premises to cope with wildfire smoke risks. Additionally, it is helpful to review how a building performed during a previous wildfire and whether past mitigation strategies worked.
Continuous monitoring can help identify spikes in PM2.5 and help inform further decision-making and mitigation steps. For example, it can show what part of a building is affected by wildfire smoke and whether localized air purifiers might be needed to counteract areas that are not sufficiently covered by existing HVAC or other air quality control systems. Indoor air quality monitoring can also integrate with building management systems to automate closing dampers or increase ventilation.
4. Preparing for an Emergency with Proper Planning and Communication
Those responsible for building management should have access to a clear action plan with agreed-upon protocols for keeping building occupants safe. Organizations should communicate this plan to the entire company or building and regularly review it to ensure it is current and that people know what actions they need to take.
While best efforts to minimize smoke entry into a building can be very effective, there are instances where further action is needed to keep people safe. For example, if PM2.5 particles remain high across the building despite adjusting ventilation and sealing the building, it might be necessary to evacuate the premises and send people home.
5. Tailor Plans According to History and Geography
A risk management plan should also incorporate an understanding of wildfires’ previous impacts on your region. For example, mitigation plans will be different if you know that your building is in the direct path of a wildfire or there is an established pattern of residual smoke exposure and lasting effects of wildfire smoke. Every risk management professional should tailor their preparedness plan to their location’s unique circumstances and play a proactive role in monitoring fires in their area, especially during summer months.
6. Ensure Occupants Understand Risks
Communication is essential to ensure successful implementation of any risk management plan. Establishing, distributing and regularly reviewing clear protocols for what building occupants should do in the event of a wildfire helps ensure the effectiveness of other risk management strategies.
Some protocol examples are:
- Ensure people understand when and why they should not open windows and exterior doors
- Set up clear communication channels in an emergency, such as how to check for information or when it is necessary to stay home
- Initiate a process for how building occupants can escalate issues, for example, if windows are not closing properly or if HVAC systems are not working