Mayor Eric Garcetti joined a growing push for residents to wear face coverings when out in public.
The Centers for Disease Control and Prevention has argued that healthy people do not need a mask if they are not working in healthcare or caring for an infected person.
But in recent days, the CDC has been weighing whether to modify its recommendations and endorse the use of homemade masks.
“I can tell you that the data and this issue of whether it’s going to contribute [to prevention] is being aggressively reviewed as we speak,” Dr. Robert Redfield, the CDC director, told NPR.
Riverside County released the new mask guidance Tuesday, covering such essential tasks as grocery shopping and medical visits.
“The face coverings do not have to be hospital grade but need to cover the nose and mouth. For example, bandannas, fabric masks and neck gaiters are acceptable. Fabric covers and bandannas can be washed and used again,” the county said.
Officials said the recommendation is based on new knowledge about the coronavirus.
“When the situation changes, the rulebook changes,” Dr. Cameron Kaiser, Riverside County’s public health officer, said in a statement. “We’re seeing our numbers increasing even sooner than we predicted and that means our strategy must change too.”
At a Wednesday afternoon news briefing, Garcetti said he had been awaiting advice on masks from the CDC but with the COVID-19 rate surging had decided to wait no longer.
The mayor said everyone performing essential tasks such as as food shopping should wear homemade, nonmedical face coverings, or even bandannas, as people in other countries have done.
“To be clear, you should still stay at home. This isn’t an excuse to suddenly all go out,” Garcetti said.
He added that people shouldn’t use medical-grade masks, which are in short supply and are needed by healthcare workers and first responders.
The Associated Press contributed to this report.