A gas leak this morning prompted the evacuation of 100 people inside the Birck Nanotechnology Center at Purdue University for more than an hour.

No one was injured.

The university’s fire department responded to an automatic gas alarm at the building on the south end of campus. Those evacuated were sent to the nearby Burton D. Morgan Center for Entrepreneurship while a hazardous materials team swept Birck to find the leak’s source, according to fire Chief Kevin Ply.

He said a krypton/flourine gas leak was found in a first-floor lab, near the building’s cleanroom. The gas concentration was well-below hazardous levels.

The leak occurred around the seal of a closed system, meaning there was little chance for human exposure, Ply said in a news release.

Krypton/fluorine is an ultraviolet laser gas used to etch and deposit materials onto substrates, such as the silicon used to make up the base layer of integrated circuits.

Ply said crews were working to repair the leaking seal.