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Reducing Exposure to Wildfire Smoke: How Effective are Do-It-Yourself and Solar-Charged Air Cleaners?

When wildfires impact air quality, health officials recommend sheltering indoors to avoid breathing in the tiny particles that are in smoke. However, indoor air quality can also reach unhealthy levels during smoke events. Heating, ventilation and air conditioning (HVAC) systems or portable air cleaners can help by filtering the air. But cost, availability, and access to a reliable power source (especially during fire events) can be barriers to their use. As a low-cost solution, some people are making Do-It-Yourself (DIY) air cleaners (sometimes called a “filter fan”), with one or more store-bought air filters attached with screws or duct tape to a standard box fan. 

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