Fresno Bee Newsroom Blog

Exceedances v. violations of air standard

Pop quiz: When the Valley’s air breached the federal ozone standard earlier this month, was it an exceedance or a violation?

In federal air-speak — a legal language invented over the past few decades — it was an exceedance, not a violation

Air quality was a concern during this Cross City Race several years ago.

I called it a violation, which I think is easier to understand when we’re speaking in general terms. I sparingly use the term exceedance when I’m explaining the law or its consequences.

But maybe it’s time to start using both exceedance and violation, and explaining the difference each time for clarity. What do you readers think?

So, let’s talk about difference. You need three exceedances at a monitor to get an official violation. You can see why people who know the difference are upset when I write that the Valley’s two March breaches — now I’ve invented my own air-speak — are violations.

In the legal world, it’s an important distinction. Exceedances are cause for concern. Violations can knock your community out of compliance with the standard. That can lead to penalties and expense for the community involved.

How does a community achieve the federal standard? A federal official emailed me this several years ago:

“A community will meet the eight-hour standard when the three-year average of the annual fourth highest daily maximum eight-hour ozone concentration measured at each monitoring site is less than 76 parts per billion (ppb).”

I’ve just been writing that we need zero violations. I’m pretty sure that would work — for both exceedances and violations.

Honestly, I’ve never been able to write a sentence about the “three-year average of the fourth annual highest daily maximum” and really make it sing.

But I am now seriously thinking of switching from my conversational use of “violations” to the combination of exceedances and violations. Maybe there is value in making the distinction each time I refer to it.

For those who are still awake after reading this, let me know what you think.