From the Associated Press
Indiana officials are working to formalize regulations for tornado sirens, but some counties could decide not to install them.
The regulations being finalized by the Indiana Department of Homeland Security allow each county to decide whether it needs sirens.
The agency recommends sirens for counties with more than four homes per acre and for urban and commercial areas with more than 2,500 people present per square mile during the day. Sirens also are recommended near major highways.
