California has confirmed indoor concerts, theatres, sports and other private gatherings will be able to restart from April 15.

The US state’s Department of Public Health updated its blueprint to reopening allowing additional activities to resume with modifications to reduce risk.

In order for people to attend the reopened events, proof of vaccination against COVID-19 or a negative test result will be required for entry.

The number of guests allowed at the event or gathering will be determined by which four-color restriction tier the specific county is in.

Indoor live events or performances will be banned in the Purple Tier, while they will be allowed from April 15 in the Red, Orange and Yellow tiers with capacity limits and modifications including physical distancing, advance ticket purchases, designated areas for eating and drinking, and attendance limited to in-state visitors.

Indoor sports arenas in California will also be able to welcome back a limited number of spectators, with NHL and NBA venues in the state to be permitted to admit fans, also with capacity limits varying depending on the county

Mark Ghaly, secretary of the California Health and Human Services Agency, said: “Today’s update to the Blueprint for a Safer Economy is a result of the progress we are making both in vaccinations and in controlling the spread of COVID-19. By following public health guidelines such as wearing masks and getting vaccinated when eligible, we can resume additional activities as we take steps to reduce risk.”

For venues with a capacity of up to 1,500 people, the capacity is limited to 10 per cent or 100 people in the Red Tier, and capacity increases to 25 per cent if all guests are tested or show proof of full vaccination.

In the Orange Tier, capacity is limited to 15 per cent or 200 people, and capacity increases to 35 per cent if all guests are tested or show proof of full vaccination. While in the Yellow Tier, capacity is limited to 25 per cent or 300 people, and capacity increases to 50 per cent if all guests are tested or show proof of full vaccination.

Meanwhile, for venues with a capacity of 1,501 and above, testing or proof of vaccination is required in the Red Tier and capacity is limited to 20 per cent. In the Orange Tier, capacity is limited to 10 per cent or 2,000 people, and capacity increases to 35 per cent if all guests are tested or show proof of full vaccination.

In the Yellow Tier, capacity is limited to 10 per cent or 2,000 people, and capacity increases to 50 per cent if all guests are tested or show proof of full vaccination.

The department also recommends that private events or meetings, such as conferences or receptions, use pre-purchased tickets, defined guest lists and assigned seating to reduce exposure risk.

Dee Dee Myers, senior advisor to Governor Gavin Newsom and director of the Governor’s Office of business and economic development, said: “As we continue to expand vaccine distribution, California is poised for a safe and equitable recovery. We will continue to work with businesses, arts organisations, community groups and others to open carefully, with health and safety top of mind, so that we never have to go backwards.”