Dust bunnies soured the theater experience for hundreds of patrons attending "Troilus and Cressida" at the Oregon Shakespeare Festival today.

Dust bunnies soured the theater experience for hundreds of patrons attending "Troilus and Cressida" at the Oregon Shakespeare Festival today.

(Updated 4:45 p.m.) During intermission, the wail of a fire alarm in the New Theatre emptied the building after a puff of dust triggered a smoke detector in a ventilation duct, fire crews and OSF officials suspect.

“It happens about once a year in the New Theatre … dust particles get into the system and trip our alarm,” said Amy Richard, OSF communications manager.

Last year, a false alarm interrupted a performance of "Julius Caesar” in the New Theatre, she said.

Patrons were evacuated for about 15 minutes before re-entering the building, Ashland Fire & Rescue Battalion Chief Kelly Burns said.

"Shakespeare has their stuff pretty squared away," Burns said. "They did have to evacuate … We chased down where the detector was and confirmed there wasn't any fire."

Crews responded to the alarm at 3:15, Burns said.

— Sam Wheeler