The rare shutdown of two St. Louis Park schools over fears that worn floor tiles could be releasing asbestos is prompting dozens of Minnesota schools to reexamine their own floors.

"Our phone has been off the hook all day," said Diedra Hudgens, senior project manager at the Institute for Environmental Assessment, which counts St. Louis Park among the 60 school districts for which it does asbestos testing. "I think every district could learn a lesson from this."

Hudgens said the Brooklyn Park company heard from many of them Tuesday and plans to send them a floor maintenance fact sheet.

St. Louis Park junior and high schools will reopen Wednesday after being closed for two days. Staff in the west metro district complained last week about asbestos floor tiles that were worn down by tracked-in salt and sand, losing the wax layer that prevented dangerous asbestos from being released.

IEA last tested the school district in November and found no safety problems, according to records from the district's asbestos plan. Such plans are required by the federal Environmental Protection Agency. The next inspection is scheduled for May, records show.

"We have plans and we follow our plans," district spokeswoman Sara Thompson said.

The suspect tiles were removed and on Tuesday evening, crews were still busy at the high school, cleaning and testing other areas of the school. After the cleaning and additional testing, some floor areas will be resurfaced.

Other school districts will likely be taking note.

"'How do we make sure we don't have that problem?' I bet that conversation is going on in at least 40 school districts," said Charlie Kyte, the executive director of the Minnesota Association of School Administrators. "Everybody kind of panics about this."

Asbestos floor tile was commonly installed in hundreds of 1950s and 1960s-era schools across the metro area. Since then, many schools have removed the asbestos while those that still have asbestos materials are required by federal guidelines to reinspect it every six months.

In St. Louis Park, the senior high school was built in 1955 and expanded in 1962, 1967 and 2002. The district couldn't say when the floors were last waxed or how much it costs.

Phil King, EPA's Region 5 asbestos coordinator in Chicago, said he's not aware of any broad problem with de-icing salt disrupting asbestos-containing floor tile in schools. But he said the tile itself is "very common" in U.S. schools and routinely wears out.

King said schools are not required to notify the EPA when asbestos-containing floor tile becomes "friable," or worn to the point of crumbling or cracking, raising the danger of dangerous asbestos being released into the air. But the schools must address friable floor conditions according to regulations and update their own asbestos management plan.

"When it becomes friable they are required to take a timely and appropriate response action," King said. Inhalation of asbestos can cause lung cancer and other deadly diseases.

Experts: No cause for worry

Experts say that parents shouldn't worry about students' safety at schools where there's asbestos tile because the tile contains relatively low concentrations of the dangerous mineral. And as long as it's contained, such as by a wax layer like at St. Louis Park High School, it remains safe.

School districts such as Wayzata have gotten rid of asbestos tile since the 1950s and 1960s. Only 10 percent of the original asbestos remains in six Wayzata schools and 80 percent of that is tile that is under carpet and isn't a concern, Wayzata district spokesman John Sucansky said. "We remove asbestos every year as long as we can financially afford to."

Audrey Bomstad, a finance official at the Minnesota Department of Education, said asbestos-related floor replacement projects are common within a state program that provides financial assistance to needy school districts for health and safety projects. The program started in 1986 with the passage of the federal Asbestos Hazard Emergency Response Act.

While Hudgens said that it's rare for her company to come into school districts and have to shut down school to clean and test for asbestos, the district spokeswoman said they weren't taking any chances.

"As a precaution, we wanted to do the testing throughout the school," Thompson said, adding about concern the district overreacted: "We don't think so. I think it's in the best interest of students and staff."

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