Myths

1. Myth: If I can’t see or smell air pollution, the levels (concentrations) of the pollutants is health- acceptable. Fact: Most air pollutant gasses are nearly invisible (e.g. carbon monoxide). Some pollutants can become visible but only if seen through miles of atmosphere e.g. a smog “haze” seen hovering over a distant city. Most pollutants also reach health-hazardous concentrations well before they can be detected with our noses (if this were not the case, early miners would not have had to take canaries into the mines with them). 2. Myth: Particulate matter (PM) emissions are not a problem if the emitted amounts are reasonable. Fact: Particulates occur in the atmosphere due to both direct emissions (e.g. soot from a jet engine) and “secondary” chemical reactions. Gasses can combine with other gasses, often under solar energy driven conditions, to form new products that exist as particles. This is particularly true for reactions involving VOC’s (volatile organic compounds) and oxides of nitrogen or NOx (produced burning fuels in the presence of atmospheric nitrogen). 3. Myth: The human body has protective functions that “filter out” particulate matter, preventing it from harming us. Fact: Particulate matter is characterized by its particle diameter, amongst other aspects. Dusty conditions in nature have caused humans to evolve with protection systems such as nasal hairs and mucus (to flush away dust). But these dusts are comprised of relatively large particles, typically greater than 10 microns in diameter. Particulate matter emitted directly from combustion engines or secondarily formed are…

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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 [...]