Most states require that security guards be licensed. Individuals must usually be at least 18 years old, pass a background check, and complete classroom training in such subjects as property rights, emergency procedures, and detention of suspected criminals. Drug testing often is required, and may be random and ongoing.
Each state has its own licensing requirements for both armed and unarmed security guards. After clicking on a state below, type in "security guard" in their search box. If the state has published its laws and regulations, you will get back the information you need.