NEW YORK (CBSNewYork) — New York City unveiled Thursday new guidelines to determine when public schools must close because of coronavirus cases.

It comes just one day before parents have to make a decision about how their kids will attend classes, CBS2’s Aundrea Cline-Thomas reported.

READ MORE: Glen Rock High School Shuts Down In-Person Learning Due To Spike In COVID Cases After Spring Break

PS 192 in Harlem is temporarily closed because of two unrelated COVID cases at the school.

There have been nearly 850 building closures across the city since September, creating hardships on in-person learning.

“It’s a little bit difficult because sometimes they miss a lot of classes and remote learning sometimes is hard for us to do,” parent Mabelene Santiago said.

COVID VACCINE

Starting Monday, the policy changes will make it harder for schools to completely shut down.

“The era of disruptive, 24-hour closures is over,” city Health Commissioner Dave Chokshi said.

Now if there are two or three cases in a school, the building will remain open while the affected classes will go remote for 10 days, and random testing would double to 40% of staff and students.

Schools would close only if four or more unrelated cases could be traced back to the school.

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“We’ve documented the harm that can occur from disrupting the social, emotional and educational development of children, and we’re balancing that with the data that we’ve learned,’ said Dr. Jay Varma, the city’s senior advisor for public health.

Data that shows the infection rate in schools remains low, and that least 65,000 staff members — often the source of transmission — have been vaccinated.

Still, the COVID variants pose concerns, and national health experts say could be more transmissible among kids.

“I do feel confident that we can continue to apply very rigorous safety standards that will keep our schools safe even though the virus is fighting back by evolving and changing,” Varma said.

CORONAVIRUS PANDEMIC

Simultaneously, Mayor Bill de Blasio and Department of Education hope to welcome more students back to school in person — five days a week — starting this month.

“We still have the PPE, we still have the ventilation, we still have the cleaning … It’s all still there,” United Federation of Teachers President Michael Mulgrew said. “A majority of schools in New York City will be doing 40% testing on a weekly basis.”

The teachers’ union is on board, hoping more parents and students feel safe.

However, Cline-Thomas talked to many parents off camera who said they’re sticking with remote learning for now, and may reconsider in-person learning for the fall.

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The window to opt-in to in-person learning ends on Friday.

Aundrea Cline-Thomas