Thirty-nine patients at the school district building in Crandon, Wis., were treated after a mechanical issue with the furnace created elevated levels of carbon monoxide on Thursday, according to the Forest County Sheriff’s Office.

Aspirus Health confirms that the patients were all treated and released from three hospitals and one clinic.

Now, a group of northern Wisconsin Republicans in the Assembly plan to file a bill to require carbon monoxide detectors in schools.

“This traumatic event could have been avoided with a simple detector,” said Rep. David Steffen (R-4th Assembly District). “We’ve put millions of dollars into school safety programs over the years. This is an inexpensive, but very effective, way to protect our kids while they’re at school. I look forward to working with Representatives (Jeffrey) Mursau and (Rob) Swearingen to address this safety oversight.”

State law doesn’t require schools to have carbon monoxide detectors, according to the Wisconsin Department of Health Services.

“We recommend them because they are a relatively inexpensive way to protect students and staff from this invisible odorless gas,” a state spokesperson said.

Carbon monoxide is a poisonous gas you can’t see or smell that’s created when fuel burns.

After the Crandon incident, Wisconsin Gov. Tony Evers posted on social media, “Every kid, educator, and staff member should be safe in our schools. I’ll be working on a plan to help address this issue that I’ll propose as part of my upcoming biennial budget.”

Minnesota Doesn’t Require CO Detectors in All Schools

In Minnesota, the Department of Public Safety shared that carbon monoxide detection systems are required in newly constructed Group E (school) buildings. However, they aren’t required in existing schools.

The state rule requires schools constructed on or after March 31, 2020, to have carbon monoxide detectors.