Metro Support Unit 5 (MSU5) was placed out of service, marking the end of an era. MSU5 was placed in service in 1985 and was purchased by the Washington Metropolitan Area Transit Authority (WMATA) and equipped with forty (40) self-contained breathing apparatus, rated at one hour, for use in operating in the tunnels of the Metro Rapidrail System. This was one of three units within the entire Metro system and would respond to emergencies involving Metro in the entire Washington metropolitan area. Over time mass casualty supplies were added to the unit to make it more versatile.