Abstract: A disposable safety needle and syringe assembly includes a needle shield movably positioned within a syringe housing. Movement of the needle shield from the housing is effected by movement of the syringe plunger and plunger piston following completion of an injection whereby the needle shield envelopes the needle extending from the housing to prevent accidental needle sticks. The plunger piston is disengagable from the plunger at a limit of travel upon retraction of the plunger, thus maintaining the shield in a locked position enveloping the needle. The syringe and needle assembly can then be safely handled for disposal, and the possibility of inadvertent reuse of the needle and syringe is eliminated.

Abstract: A single use needle assembly includes a needle extending through a base with a hub extending from the base for engaging a syringe. The end of the needle within the hub has a port which is covered by a retractable sheath. When the needle assembly and a syringe are assembled, two separable tabs held within a basket force the sheath to retract and expose the port in the needle whereby a fluid can flow through the needle. Upon disassembly of the needle syringe, the tabs separate from the basket and are effectively destroyed for further use in retracting the sheath.