What do white curbs in San Francisco mean?
White curbs in San Francisco denote zones for passenger loading and unloading of no more than 5 minutes. Time zone enforcements for white zones will vary and are indicated by signs or on the white curb. Drivers must remain in vehicles at all times unless at a preschool or hospital.
Typical locations for white curb zones in San Francisco are hospitals, senior centers, medical offices, restaurants with valet parking, hotels, apartment or condominium buildings with more than 50 units, churches, schools and government buildings.