Sanitary safety device

A flow-control cartridge for insertion into a tubular conduit comprising:

• a. a cylindrical tubular housing having a plurality of inside diameter portions and having an upstream end and a downstream end and an outward peripheral element adapted to center the housing in the tubular conduit,
• b. a plurality of separate and independently structured cylindrical flow-control insert elements having respectively the same outside diameter as the inside diameter of the portions and disposed snugly in stacked relation inside the respective portions, the insert elements comprising:
• (1) a backflow preventor comprising a first annular body having an upstream end and downstream end and having a valve seat at its upstream end, a spider unitary with the first annular body and having a central tubular hub at the downstream end and a valve element comprising a head disposed adjacent the valve seat and a stem extending slidably in the tubular hub, and a spring disposed around the stem and between the spider and the head and biasing the head toward the seat, and
• (2) a flow restrictor comprising a second annular body formed with a central opening and a concentric annular trough facing the upstream end of the tubular housing, the trough having an inner margin, the second annular body having ports therethrough arranged outward from the inner margin and a resilient O-ring disposed in the trough normally adjacent the inner margin and adapted under pressure to expand outward to partly cover the ports and restrict flow,
• c. inward retaining means in the housing for retaining the insert elements from moving axially of the housing.