Most campus buildings and facilities are generally accessible to members of the campus community, guests, and visitors during normal business hours, Monday through Friday, excluding holidays. Certain facilities may also be open for designated hours on evenings and weekends. Exterior doors on campus buildings are locked and secured each evening by public safety personnel. Residence hall exterior doors are generally locked 24 hours. When the residence halls are locked, entrance (where applicable) is gained by use of a valid SJC ID card.