Northwest communities are breathing easier than many places in the United States after federal regulators clamped down on ozone pollution, the main component of smog.
The Environmental Protection Area last week lowered the acceptable limit to 70 parts per billion. The new clean air standard is not as far-reaching as health and environmental advocates were calling for. But it’s more strict than many industry representatives wanted to see.
As of 2014, no region in Washington or Oregon were averaging greater than 65 parts per billion.
What is ozone?