[Source: Kate Bolnick, ASU Web Devil] — Arizona’s pollution levels showed improvement in Maricopa County in this year’s ozone season, the time of the year when pollution levels are the highest, an official said. “This year, so far, we have four exceedance days for Maricopa County,” said Maricopa County Air Quality Department spokeswoman Holly Ward. “Last year we had 18 exceedance days reported.”
Exceedance days are the number of days when at least one of the county’s monitors exceed the ozone standards, Ward said. “There [are] some core components that this department strives for… the first and foremost is to reduce the number of times [Maricopa County] exceed[s] the public health standard,” she said.
The public health standard comes from the Environmental Protection Agency’s Clean Air Act of 1970, which was amended in 1990. The standard was raised in March of 2008 to .075 parts-per-million. The act clarifies what level of pollution is acceptable and specifies only one exceedance day every three years is allowed. Arizona is in great violation of the standards, according to the act, but is improving, Ward said. [Note: Read the full article at Maricopa County pollution levels improving.]