Those who were around in the 1990s remember the grumbling about restrictions the state imposed to reduce air pollution.

Utah County residents were not happy with the idea of having to check weather reports before starting a fire in a fireplace or wood stove. Nor were they too happy about emissions standards for cars to address both particulates and carbon monoxide.

There were more than a few people willing to rebel against the U.S. Environmental Protection Agency for imposing its standards on us and setting rules for cleaning up the air.

But as we get past one of our worst winters in years, we can be grateful for those control measures.

Even though Utah County had 25 days when you couldn't light a fire, overall air quality was vastly better than it was 15 years ago, due in large part to the measures implemented to control particulates.

In the early 1990s, before the controls were implemented, PM10 levels hit 300 micrograms per cubic meter, twice the national standard. This winter, the PM10 readings were less than 130 micrograms, and that was under the worst weather conditions the county has seen in years.

While some may attribute the difference to Geneva Steel's shutdown, that would not be accurate. While Geneva was the largest single-point source of particulate pollution, the largest overall source in the area has been, and still is, cars.

Emissions testing has made a difference, as did the change to cleaner-burning diesel fuel and the fact that older, dirtier cars are being replaced by cleaner-running rigs.

While the news was good, there was some concern about the PM2.5 standards. Utah County exceeded the standard 17 times during the winter. However, that picture looks bad only because the EPA changed the standard this year, reducing it from 65 micrograms to 35. Had the old standard been in place, the PM2.5 readings would not have been as severe.

PM2.5 is also a bit more problematic in that it is created mainly through chemical reactions, rather than just being soot like the larger PM10 particles. Cars are one of the leading producers of it.

We are not in violation of this standard -- at least not yet. The EPA takes the average of three years' worth of readings before declaring an area to be in violation of PM2.5 standards. We have two years more to go, and a lot of things can happen. We should not rest on our laurels and trust that everything will work out. Let's continue to observe the current regulations and look for ways to cut down on driving.

Try walking more; it's good for you. Consolidate trips. Ride the bus. Join a carpool.

Besides cleaning up the air, such moves can also save gasoline and money, so we all come out ahead on this deal.

This story appeared in The Daily Herald on page A5.