Except as provided in subsection (b) of this section, a custodian shall deny inspection of the part of a public record that identifies or contains personal information about a person, including a commercial entity, that maintains an alarm or security system. A custodian shall allow inspection by: the person in interest; an alarm or security system company if the company can document that it currently provides alarm or security services to the person in interest; law enforcement personnel; and emergency services personnel, including: a career firefighter; an emergency medical services provider, as defined in § 13–516 of the Education Article; a rescue squad employee; and a volunteer firefighter, a rescue squad member, or an advanced life support unit member.