Major Parker.jpg IMG_4182.JPG Capt Humphrey.jpg About Us PChange Protective Services provides armed and unarmed uniform guard services. With offices in Washington DC, Hyattsville MD, Cherry Hill NJ, Boston MA, Pittsburgh PA, and Baltimore MD. PChange is a leader in providing uniformed physical security services to a variety of clients. PChange Protective Services hires highly trained security officers who have backgrounds in law enforcement, military and 5 years or more in guard services.