CALEDONIA (WWJ/AP) – Thirteen employees at a West Michigan medical supply manufacturing business who were having trouble breathing were taken to a hospital for treatment and later released, officials said Wednesday.

Caledonia Township Fire Chief Brian Bennett said the crews responded around 9:45 p.m. Tuesday to Aspen Surgical in the Caledonia area, about 15 miles southeast of Grand Rapids, following reports of employees having trouble breathing.

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“Everybody was evacuated and in order to make sure we knew what we were dealing with, we just basically set up a triage,” Bennett told WWJ’s Laura Bonnell.

EMS crews evaluated or treated 63 people at the scene and transported 13 others to a hospital. Bennett said people reported respiratory problems, headaches and other conditions.

A hazardous materials team that responded didn’t find hazardous chemicals in the air, but the facility was ventilated.

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“We called in the local HAZMAT team and they went in to check air quality. They were never able to completely come up with anything specific. They looked up the chemicals they use in there, never got a reading on any of those,” Bennett said.

Bennett said the cause of illnesses still isn’t known. He said air quality monitoring is planned Wednesday at the business.

According to its website, Aspen Surgical manufactures and sells needles, instruments and other medical supplies.

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