The EPA is expected, shortly, to announce new ozone standards for air quality. Currently, the standard is 75 parts per billion, a number which the Roanoke Valley has remained under for a number of years. Scientists recommend the standard be lowered to between 60 and 70 parts per billion. One of our coalition members analyzed how the valley’s recent air quality performance would have looked under a sample of these new values:
Ozone pollution is measured by the number of days each year that it surpasses the the standard over an eight-hour period – generally announced as a “Code Orange” or worse air quality day. Our coalition member looked at all of the eight hour averages over the past three years and compared them to three sample standard values.
Under the current standard, 75, we’ve had one violation of the standard in three years. Under the most conservative standard we’ve had 35.
Many health professionals recommend setting the standard as low as possible to have the best impact on human health, though communities contend that the lower the standard is set, the more violations of the standard are going to be affected by things outside of a community’s direct control – for example, power plant emissions being drawn in from a nearby county, or vehicle emissions from a major highway. Regardless of the source of the pollution, it’s impact on human health is clear and becoming clearer every day.