valve will prevent contamination of the fluid in the container with a product that is contained in the syringe such a valve might be used if different fluids from more than one container must be sampled in the same syringe to prevent accidental mixing of the solution in the second container that is being sampled of course when the syringe 1 is to be used the valve 8 is cut off fig7 shows a tube 2 fitted with a three port valve 9 having a lateral connection with an empty container 10 this valve 9 may allow communication between the syringe 1 and either of two pieces 2b and 2c of closed sealable tube the tube 2b can be used to connect with the solution to be aspirated via sterile docking after transfer by turning the plug of the valve 9 open fluid communication is accomplished between the syringe 1 and the other tube 2c to this other tube 2c a component can be coupled with the aid of sterile docking for instance a flexible container 10 as shown in fig7 may be connected to this tube 2c then this container can be used as for example a waste bag to collect the air that is expelled from the syringe 1 use of this three port valve in this configuration therefore makes it possible to expel the air from the syringe in a closed system this may be especially important in the preparation of cytotoxic drugs to prevent aerosols and spillage it may also be important to keep the container that is being sampled essentially free of air which may be important if the container that.