Nursing homes and many assisted living facilities across the state will finally get blanket testing for the new coronavirus under an order that Gov. Jay Inslee issued May 28.

Per the order, tests must be offered to everyone living in a nursing home by June 12 and all residents of certain assisted living facilities by June 26.

Inslee is also requiring that all staff members in those facilities be tested unless an employee gives medical justification from a health care provider declining a test.

The state will provide free test kits and personal protective equipment for administering the tests to every facility. The massive effort is expected to cost $1.5 million for nursing homes alone.

“This is going to protect some of our most vulnerable residents,” Inslee said during a news conference.

The announcement is a victory for the state’s long-term care facilities, many of which have been especially hard-hit by the virus because of residents’ advanced age and underlying health conditions.

If a facility does not receive enough test kits or protective gear, it must use every test it can safely administer and notify the state Department of Health. Otherwise, it will be considered in violation of the order.

Facilities aren’t obligated to pay laboratories for the tests. Instead, the Centers for Medicare and Medicaid Services and Washington’s Health Care Authority will pay for tests performed on all residents and staff who are covered by Medicare or Medicaid, and the state will pay for the rest, the order says.

Assisted living facilities that don’t have a memory care unit are not covered under the order. State officials chose to focus testing efforts on facilities with those units because residents there tend to wander and move around more on a daily basis, which increases the risk of infection, said Secretary of Health John Wiesman.

State officials are developing plans for widespread testing at assisted living facilities without memory care units and adult family homes, Wiesman said. They’re also considering options for interval testing at long-term care facilities to track new infections over time.

Nursing home industry advocates have for weeks pushed for broad testing at long-term care facilities, saying it’s the only way to truly understand how widely the virus is spreading.

A lack of testing supplies limited the state’s ability to do so, Inslee said. Meanwhile, research has illustrated how people who are infected often spread COVID-19 without showing symptoms, he added.

“Had we had additional testing capacity, I think we could have done these things earlier, but that’s been a great limitation,” Inslee said. “Both the science has improved, and the testing supplies have improved.”

Facilities that have completed a COVID-19 point prevalence survey of residents and staff since the beginning of April are not subject to the order, Inslee said, because they’ve already done widespread testing.

Statewide, there were 3,728 COVID-19 cases and 667 deaths linked to long-term care facilities as of Tuesday.

But “thankfully,” the state has seen a decrease in outbreaks at such facilities in the past month to six weeks, said Wiesman.

“We are looking forward to these results and learning just how much asymptomatic infection we might have in a facility,” he said.