At first, the four employees at the business thought an electrical problem was producing smoke. However, firefighters discovered it was actually a cleaning machine using corrosive chemicals that was leaking. So, they called in a hazardous materials team.
"That machine was shut off. The building was ventilated and turned over to Revcor to hire a company to do a cleanup process," said Carpentersville Fire Chief John Schultt.
The people who were exposed to the chemicals were taken to area hospitals as a precaution.
They were all released later Saturday.