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Wildfire Smoke and Your Patients' Health

Preparing for Fire Season

Smoke events can occur without warning. Before fire season, your patients can take steps to be ready. More information is available in the Wildfire Guide factsheet Prepare for Fire Season (PDF) and EPA’s web site on Wildfires and Indoor Air Quality.  Steps for your patients to take before fire season include:

Know where to find alerts: Point patients to sources in your area for alerts and health warnings about smoke and fire risk, including air quality reports, public service announcements, and social media warnings. The most reliable alerts come from state, local, or federal government agencies. The AirNow web site includes links to Current Advisories.

Develop a disease management plan: Patients with heart or lung disease should know: the symptoms of disease exacerbation, medications that can help, and when to call or come in for medical attention. Patients with asthma should have an asthma action plan.

Stock up on medications and food: Having several days of medications and food on hand will help your patients avoid having to go outside during a smoke event. They should buy at least some groceries that do not need to be refrigerated in case the power goes out, and some food that does not need to be cooked.  Cooking, especially at high temperatures such as during frying or broiling, can add particles to indoor air -- this should be minimized during very smoky periods.

Check the heating, ventilation, and air conditioning (HVAC) system: Patients should become familiar with their residence’s HVAC system so they can adjust it to keep smoke out. Important features to understand include using appropriate high-efficiency air filters and closing the fresh-air intake if the central air system or room air conditioner has one. Your patients may consider having a professional check the HVAC system and walk them through these features.

Most home systems use a low efficiency fiberglass filter that is 1 inch thick and has a Minimum Efficiency Reporting Value (MERV) rating of 1–4. Replacing this filter with a medium efficiency filter (MERV 5–8) can significantly improve the air quality in a home. Higher efficiency filters (MERV 9–12) will work even better, and a true high efficiency filter (MERV 13–16) can remove as much as 95% of the particles that pass through it. Upgrading to a filter rated MERV 13 or higher can be especially important during smoky periods to effectively remove fine particle pollution from smoke in the indoor air.

Most furnaces and HVAC systems can accommodate a MERV 13 filter without creating equipment problems, provided that the filter is replaced frequently. Sometimes it can be difficult to tell whether a system can use a higher efficiency filter since HVAC systems are not commonly labeled with any filter recommendations. To be certain a filter will work with your system, consult a professional HVAC technician. The technician can determine the most efficient filter that your system can use. An HVAC technician can also modify the system to use a higher efficiency filter. Whether patients can upgrade their filter or not, the filter should fit correctly in the filter slot and be replaced as recommended by the manufacturer.

Consider how to stay cool at home with doors and windows closed. Patients without air conditioning at home may need to purchase fans or window air conditioners as appropriate. Discourage patients from choosing portable air conditioners with a single exhaust hose during smoky periods because they can create conditions that draw more smoke indoors.

Consider buying a portable air cleaner: Portable air cleaners are self-contained air filtration appliances that can be used alone or with enhanced central air filtration to effectively remove particles. Securing an air cleaner before a smoke event occurs is particularly important for patients in at-risk groups. During a smoke event it may be hazardous to go outside or drive, and appropriate devices may be in short supply. Emphasize that the portable air cleaner should have a high-efficiency HEPA filter and be the right size device for the room. California has a table listing California-certified air cleaners Exitby brand, model number, and type. Certification is based on their low (usually near-zero) ozone emissions and electrical safety. Patients may also want to consider factors such as noise that may affect how often they use the device.

Consider purchasing respirators: Patients should consider having a supply of NIOSH-approved respirators (e.g., N95 respirators) on hand and learn how to use them. They are sold at many home improvement stores and online.

Make an evacuation/relocation plan: Patients in at-risk groups should consider making a plan for where they might stay, for example, with friends or relatives, if smoke levels are high and predicted to remain high. Organizing important items ahead of time, including financial and personal documents, will speed evacuation in case it becomes necessary.

Protect pets: Your patients can reduce pets’ exposure to smoke by including them in planning. See the Wildfire Guide factsheet Protect Your Pets from Wildfire Smoke (PDF) .