Embodiments are related to ampoule assemblies containing bypass lines and valves. In one embodiment, ampoule assembly is provided which includes inlet and outlet lines coupled with and in fluid communication to an ampoule body, a bypass line connected between the inlet and outlet lines and containing a bypass valve disposed therein. The ampoule assembly further contains a shut-off valve disposed in the inlet line between the ampoule body and a connection point of the bypass line and the inlet line, a shut-off valve disposed in the outlet line between the ampoule body and a connection point of the bypass line and the outlet line, another shut-off valve disposed in the inlet line between the ampoule body and a disconnect fitting disposed on the inlet line, and another shut-off valve disposed in the outlet line between the ampoule body and a disconnect fitting disposed on the outlet line.