LONGMONT, CO — A fire on Sunday destroyed the production room of Circuits West Inc., a local PWB manufacturer.

Consequently, the site was exposed to toxic chemicals, namely nitric acid and ammonium hydroxide, reported the Longmont fire department.

As there was no indication of arson, investigators may not explore the site, as they could be subjected to chemicals in the building, where part of the roof collapsed, a spokesman for the fire department told a local paper.

Fire officials will interview company employees, but the building was reportedly vacant at the time of the fire, making it difficult to determine the cause.

Insurance companies will likely investigate as well.

The building was condemned Monday and turned over to the company’s owners.

A representative of Disaster Restoration Inc. said it could take six to 12 months to clean the fire damage.

Patrons and staff in the surrounding area were evacuated during the blaze.