29 states and the District of Columbia currently have some form of anti-idling laws
Green Car Congress
OCTOBER 8, 2019
Twenty-nine states and the District of Columbia have laws that regulate engine idling, but each of these states has different applications of idle reduction and various exemptions. Some states regulate idling geographically, such as on school property, in business districts, or in certain counties. Other states have time limits on how long an engine may be idled, or idle limits during certain times of the year.