SALT LAKE CITY – When food trucks began proliferating more than 10 years ago, most states simply put overall health standards in place, leaving the more specific regulations to counties and cities. With more food trucks popping up all across the country, states are beginning to consolidate those rules into one cohesive package, Stateline reports.

For example, Utah recently passed a law that permits food trucks to cross county lines under one license. “As far as I know, we’re the first state to take this step,” said state Sen. Deidre Henderson, who sponsored the bill. “Unlike most issues, this was difficult in that there were no states to model after.”

So far, more than a dozen states have discussed nearly 40 proposals related to food truck regulation over the past two years, according to the National Conference of State Legislatures (NCSL). Only a few have passed into law.

Close to 300 U.S. cities play host to nearly 4,000 food trucks. “As we get more and more food trucks, we get to the point where states need to regulate this industry,” said Doug Farquhar, program director for environmental health at NCSL. All 50 states slipped food trucks under current health department regulations for restaurants.

Late last year, the food truck industry jumped nearly 8% annually in the United States from 2011 to 2016, according to IBISWorld. For food truck owners, complying with multiple local rules eats up time and money, as well as restricting their ability to cross county lines easily.