The precaution of prohibiting employees from bringing personal computing devices into a facility is what type of security control?

Physical controls are tangible countermeasures such as locks, mantraps, badge readers, and security guards that restrict physical access - not written rules about employee behavior.

Procedural controls are administrative policies, rules, and guidelines that dictate how people must behave within an organization. A prohibition enforced through policy documents, employee agreements, and conduct rules - rather than locks, cameras, or software - is by definition procedural.

Technical controls use technology such as firewalls, encryption, or MDM software to enforce security - a policy prohibition does not involve any technology mechanism.

Compliance refers to adherence to laws, regulations, or standards and is not itself a category of security control in this classification scheme.