Irvine will likely become the third city in Orange County to allow marijuana businesses, following Santa Ana and Costa Mesa.

Marijuana testing laboratories are set to be allowed in industrial, medical and science districts, the City Council voted 4-0 Tuesday, Jan. 23. Councilwoman Lynn Schott was absent.

The change to zoning requires a second vote by the council, expected to take place Feb. 13. The new rules could take effect March 13.

“This is a well thought out ordinance,” Councilman Jeff Lalloway said. “I think there are a number of protections for the city including where it is in the city, the restrictions on the permitting process … There’s been no discussion about dispensaries, manufacturing, distribution, which are still prohibited under our ordinance.”

Marijuana testing labs would be required to be at least 600 feet from homes, schools, day cares or youth centers and would require a permit from the city.

Irvine has explicitly banned commercial uses of marijuana — including cultivation, delivery and the operation of dispensaries — within city limits since January 2016. Officials said at the time they wanted to maintain local control as the state established a licensing program and rules for marijuana businesses.

However, Irvine has been approached about allowing the testing of marijuana, which is strictly regulated by state law.

The labs test samples of medicinal or recreational marijuana for distributors, checking for contaminants such as heavy metals, pesticides, solvents and other impurities. If the samples pass the tests, the batches from which the samples originated may be sold at retail stores.

If the council gives the final approval in February, Irvine will become the second city in Orange County to allow marijuana testing labs.

Costa Mesa voters in 2016 supported allowing some medical marijuana businesses to operate in a northwest portion of the city. No dispensaries or retail sales are allowed, but research and testing, transportation, distribution and the manufacturing of medical marijuana-related products are approved. Two applicants, one that distributes and transports products and another that extracts hash oils from marijuana plants, are in the pipeline at Costa Mesa City Hall.

La Habra is considering allowing commercial cannabis distribution facilities. Santa Ana is the only city in Orange County that allows sales of marijuana.

To learn more about marijuana laws in Southern California cities, check out the Register’s database here.

Louis Casiano and Brooke Staggs contributed to this report.