Smoke does not play by the rules. When a prescribed burn is lit in Central Oregon, the state’s rules say Bend and Redmond are not to get any smoke intrusions at all.

That has proven to be nearly impossible. And with that standard, it can be difficult to plan a burn.

The state is in the process of revising the smoke management rules, intending to add needed flexibility. But Deschutes County commissioners are scheduled to discuss on Wednesday how one new aspect of the rules will not give the county the latitude it needs.

Striking the right balance on prescribed burns is almost doomed to fail. For starters, some forest scientists dispute the value of prescribed burns. They say there’s evidence that limited prescribed burns don’t do much for the forest or won’t appreciably reduce the severity of the most intense fires.

The debates don’t end there. Even a small whiff of smoke can cause serious problems for people with asthma and many other medical conditions. Does that mean all burns should be banned? It’s also difficult for science to say precisely how much smoke is safe.

One proposed change in the state rules is a change in the definition of a smoke intrusion. As we said, in areas such as Bend and Redmond, there are supposed to be no intrusions from burns. The state is considering revising that level from zero to “a one-hour threshold at or above 70 micrograms per cubic meter and a 24-hour average at or above 26 micrograms per cubic meter measured midnight to midnight on the first day of smoke entrance into a community.”

It adds flexibility. But it worries county officials. A draft letter from the county says the 1-hour threshold is a step backward. Deschutes County Forester Ed Keith said most of the prescribed burns in the last five years within 5 miles of Bend would have violated that threshold.

Towns in Central Oregon are extremely vulnerable to wildfire. That’s part of where we live. But the rules for smoke from prescribed burns shouldn’t be so restrictive to prevent the community from better protecting itself.