Railroad contractors will be testing signaling equipment Friday in Cotati, which could cause traffic delays, officials said.

Workers building the Sonoma-Marin Area Rail Transit tracks will be testing the device from 9 a.m. to 4 p.m. at the East Cotati Avenue railroad crossing. The contractors will be running a freight train through the crossing multiple times to test the newly installed warning lights and bells.

Flaggers will stop traffic as the train passes through the crossing during test runs. Motorists can expect delays at the crossing and are advised to use alternative routes such as Southwest Boulevard.