As used in this chapter, unless the context requires a different meaning: “Emergency medical services personnel” means any person who holds a valid certificate issued by the Commissioner and who is employed solely within the fire department, emergency medical services agency, or public safety department of an employing agency as a full-time emergency medical services personnel whose primary responsibility is the provision of emergency care to the sick and injured, using either basic or advanced techniques. Emergency medical services personnel may also provide fire protection services and assist in the enforcement of the fire prevention code. “Employing agency” means any municipality of the Commonwealth or any political subdivision thereof, including authorities and special districts, that employs firefighters and emergency medical services personnel. “Firefighter” means any person who is employed solely within the fire department or public safety department of an employing agency as a full-time firefighter whose primary responsibility is the prevention and extinguishment of fires, the protection of life and property, and the enforcement of local and state fire prevention codes and laws pertaining to the prevention and control of fires. “Interrogation” means any questioning of a formal nature as used in Chapter 4 (§ 9.1-500 et seq.) that could lead to dismissal, demotion, or suspension for punitive reasons of a firefighter or emergency medical services personnel.