From: http://co.fairbanks.ak.us/airquality/AQNearRealTime.aspx and http://airnow.gov/index.cfm?action=resources.conc_aqi_calc
At 8:00 am. on Friday November, 28, 2014, the Fairbanks North Star Borough/ADEC site indicates 106 ug/m3L particulate air pollution level as “unhealthy for sensitive groups” air quality at North Pole Water site:
but putting the same 106ug/m3L into the EPA Air Now site shows 106 ug/m3L at “unhealthy” air quality. Why is the same pm2.5 concentration graded as less dangerous by FNSB “Near Real Time” postings than by EPA Air Now?
According to the World Health Organization’s Air Quality Guidelines Global Update 2005,“The evidence on airborne PM and public health is consistent in showing adverse health effects at exposures experienced by urban populations in cities throughout the world, in both developed and developing countries. The range of effects is broad, affecting the respiratory and cardiovascular systems and extending to children and adults and to a number of large, susceptible groups within the general population. The risk for various outcomes has been shown to increase with exposure, and there is little evidence to suggest a threshold below which no adverse health effects would be anticipated. In fact, the lower range of concentrations at which adverse health effects has been demonstrated is not greatly above the background concentration, which has been estimated at 3–5 μg/m3 in the United States and western Europe for PM2.5. The epidemiological evidence shows adverse effects of particles after both short- and long-term exposures.”
northpolecleanair 