California is requiring a 21-day quarantine for people traveling from Ebola-stricken areas who have had contact with infected patients.
But the state says it's defining the word "quarantine" loosely. It could mean someone's isolated at home, or other limitations on their freedom of movement. Or, it could just mean periodic observation and monitoring, according to the new state guidelines.
California officials say it will be up to local health officials to determine which steps to take, based on a person's level of risk.
The state health department says its Ebola guidelines are in line with those out of the Centers for Disease Control and Prevention. But the CDC does not use the word "quarantine" in its guidelines.
And that word - "quarantine" - could deter California health care workers from traveling to West Africa to fight the epidemic, says Kristi Koenig, director of UC Irvine's Center for Disaster Medical Sciences.
"If this is misinterpreted to be very extreme, such as the policies that were put out by the governors of New York and New Jersey, that could be very problematic," Koenig says.
California is imposing the risked-based quarantines after the governors of New Jersey and New York were criticized for ordering mandatory quarantines. The Pentagon says troops returning from Ebola missions will be isolated.
Officials have not said how many people, if any, have been quarantined. There are no reported or confirmed cases of Ebola in California.