The needle assembly is provided with the housing, an IV cannula for accessing a blood vessel and a non-patient cannula for communication with an evacuated tube. A flashback chamber is provided in the housing at or near the distal end of the housing. A shield is hinged to a portion of the housing proximally of the entrance to the flashback chamber. As a result, good visibility of the flashback chamber is achieved. After use, the shield can be rotated into a closed position for surrounding the IV cannula and avoiding accidental needle sticks.