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Page 1 of 2 DOH 333-208 August 2015 Improving Ventilation and Indoor Air Quality during Wildfire Smoke Events Recommendations for Schools and Buildings with Mechanical Ventilation Overview • Smoke is a complex mixture of carbon dioxide (CO2), water vapor, carbon monoxide (CO), hydrocarbons, other organic chemicals, nitrogen oxides (NOX), trace minerals, and particulate matter. o Particulate matter consists of solid particles and liquid droplets suspended in the air. Particles with diameters less than 10 microns (PM10) are upper respiratory tract and eye irritants. o Smaller particles (PM2.5) are the greatest health concern – they can be inhaled deep into the lungs, and can affect respiratory and heart health. o Carbon monoxide, a colorless, odorless gas produced by incomplete combustion, is a particular health concern and levels are highest during the smoldering stages of a fire. • Outdoor (ambient) air pollutants, including smoke, enter and leave buildings in three primary ways: 1. Mechanical ventilation systems, which actively draw in outdoor air through intake vents and distribute it throughout the building. 2. Natural ventilation (opening of doors or windows). 3. Infiltration, the passive entry of unfiltered outdoor air through small cracks and gaps in the building shell. • Tightly closed buildings reduce exposure to outdoor air pollution. Upgrading the filter efficiency of the heating, ventilating, and air-conditioning (HVAC) system and changing filters frequently during smoke events greatly improves indoor air quality. Supplementing with HEPA filters, particularly those with activated charcoal or other adsorbents, improves air quality even more. • During long-term smoke…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]