On August 17, 2021, the Los Angeles County Department of Public Health announced a mask mandate for large outdoor mega-events of more than 10,000 people. This is the first outdoor mask mandate since the County began its reopening attempt on June 15, 2021.

All attendees at those events must now wear face masks at all times, except when actively eating or drinking. Event operators are required to prominently include information about the mask mandate throughout the event and on communications to guests. The County also has a recommendation (but not a mandate) that all attendees at outdoor mega-events be fully vaccinated against COVID-19, or obtain a negative test before attending the event.

Large indoor events of more than 5,000 people require that attendees be fully vaccinated or have a negative COVID test before entering the building. Attendees are required to wear face coverings while indoors.