What is the social security department?

Refers to the safety management section.

The Public Security Management Section mainly manages and regulates the service behaviors of security service organizations and security guards within its jurisdiction, examines and approves security service organizations (security companies, security guards recruited by enterprises and security guards of property companies), examines and approves self-recruited units, supervises and manages security guards, and examines, accepts, inspects, supervises and bans illegal security organizations and "black security guards" and illegal sales points of security clothing.