SAN RAFAEL (CBS SF) — San Rafael police are advising motorists to use caution at railroad crossings now that the Sonoma-Marin Area Rail Transit District begins testing its passenger service schedule Friday between Santa Rosa and San Rafael.

The tests mean the train’s horn will not sound at crossings in Marin County unless there is an emergency, the SMART District said.

Residents along the 43-mile line have complained about the loudness of the horn during rail car, crossing gate and train control systems testing since late last year.

The Novato, San Rafael and Petaluma city councils have approved quiet zones prohibiting sounding the horns at crossings in their jurisdictions.

SMART objected to establishing quiet zones during testing claiming they will confuse pedestrians, endanger public safety and expose SMART and the cities to liability.

SMART said it supports establishing quiet zones after testing is completed when the train horn noise issue can be addressed and supplemental safety measures are in effect. Those measures include an additional set of crossing arms and a raised concrete barrier to prevent vehicles from driving around the crossing arms in the quiet zones.

The California Public Utilities Commission’s Rail Safety Division recommended Petaluma delay establishing quiet zones until the trains have been in “revenue service” for at least six months

In April, the Federal Railroad Administration approved Petaluma’s establishment of a quiet zone during the testing.

The SMART train tests that begin today involve running about 30 trains trips a day on weekdays and 10 trips on weekends between Santa Rosa and San Rafael for the next few weeks.

“As jurisdictions begin establishing quiet zones, please be aware that you may not hear train horns at railroad crossings,” SMART said in a news release Wednesday.

SMART passenger service is scheduled to begin before the start of summer.

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