Some 70% of Americans would be able to remove their masks indoors, including inside schools, under new guidance to be released Friday by the Centers for Disease Control and Prevention, according to two officials briefed on the plan.

       Under the new metrics, more than half of U.S. counties, which make up 70% of where Americans live, will be in areas deemed "low" or "medium" risk because of the reduced number of COVID hospitalizations. The CDC would no longer recommend that these communities insist on indoor masking, said the officials, who spoke on condition of anonymity because they were not authorized to discuss the details ahead of the announcement.

       A CDC requirement that people continue to wear masks on public transportation, however, will remain in force for now, according to one official.

       The new recommendations represent a seismic shift in how the federal government is approaching pandemic guidance. Under previous rules, the CDC considered primarily COVID case counts to determine risk. And because case counts have remained high, the public health agency has stuck to its recommendation of indoor masking.

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       But that approach didn't take into account that most vaccinated people who tested positive during the omicron and delta waves experienced mostly mild symptoms that did not require hospitalization.

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       Dr. Rochelle Walensky, Director for Centers for Disease Control and Prevention, speaks during a Senate hearing on the COVID-19 response, March 18, 2021, on Capitol Hill in Washington.

       According to the two officials who spoke to ABC News, the CDC would now consider three factors: new COVID hospitalizations, hospital capacity, and new COVID cases. Taken together, the new CDC metrics will consider an area to be "high," "medium" or "low" risk.

       Based on that risk level, which could fluctuate, a community could opt to remove mask recommendations indoors. If those risk factors climbed, putting a community at "high" risk, the CDC recommends that people return to masks and other steps like increased surveillance testing.

       The CDC guidance is an acknowledgement that hospitalization rates in recent weeks have fallen dramatically and that highly vaccinated communities will be able to withstand an uptick in cases without overwhelming their local hospital systems.

       Jon Cherry/Getty Images, FILE

       A child acting as hallway monitor watches as children move about a hallway wearing COVID-19 protective masks at Carter Traditional Elementary School in Louisville, Ky., Jan. 24, 2022.

       Schools will not be treated differently under the new guidance as other indoor spaces, the officials told ABC.

       The updated guidance comes after weeks of pressure from governors and state officials who asked for a clear roadmap at the national level.

       A majority of states have already announced plans to drop mask mandates. Still, the new benchmarks could be used by local leaders, school boards and public health officials who are facing vastly different versions of the pandemic even within the same state.

       The guidance also is intended to give local officials a roadmap to re-imposing restrictions if another variant pops up, which health experts warn is a possibility.