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LOGAN, Utah (AP) — A Utah State University research professor has measured how much air pollution can seep into homes on days authorities are issuing warnings about high soot levels outdoors.
The Herald Journal reports environmental engineering professor Randy Martin found levels of extremely fine soot to be a quarter of the level outdoors.
That means some soot still makes its way indoors. Martin says the best furnace filters can help.
Martin and graduate students measured tiny particles of soot that are 30 times thinner than a strand of human hair - the kind that can lodge deep in the lungs and trigger respiratory and heart problems.
Martin says soot particles from tailpipe and other emissions tend to turn gaseous in warmer air, reducing the health risk.
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