From the Context: "Mass gatherings and large community events bring people from multiple communities into close contact with each other and have the potential to increase COVID-19 [coronavirus disease 2019] transmission. One method to slow the spread of respiratory virus infections, including COVID-19, is by increasing social distancing (reduce close contact). The goals of this guidance are: (1) to protect people attending and working at the event and the local community from COVID-19 infection; and (2) to reduce community transmission and introductions of COVID-19 into new communities."
California Department of Public Health
California Department of Public Health: https://www.cdph.ca.gov/