Work at Thornwood High School in South Holland Tuesday triggered a fire alarm but no fire broke out, officials said. Sanding related to a renovation project at the school, 17101 South Park Ave., set off the alarm, according to Mary Ann Thornton, spokeswoman for Thornton Township High School District 205. South Holland fire Chief Brian Kolosh said that no fire broke out but said the alarm was set off due to maintenance of duct work.