SMART train engineers continued blowing horns at crossings in Petaluma Wednesday despite the city implementing a so-called quiet zone to limit the routine sounding of horns.

Petaluma has gone through the process for becoming the first city in Sonoma and Marin counties to restrict train horns. The city installed signs at all eight crossings warning motorists of the change. Wednesday was the first day the noise ban went into effect.

But SMART says it won’t abide by the designation, citing ongoing testing and safety concerns.

Farhad Mansourian, the rail agency’s General manager, is planning to update SMART’s board of directors at their meeting today in Petaluma.