A needle assembly, comprising: a housing having a flash chamber, and having a distal end and a proximal end engageable with a specimen collection container； a cannula, the patient end of the cannula projecting at least partially from the distal end of the housing, the cannula interior in fluid communication with the flash chamber； and a shield restrainably engaged with a portion of the housing and axially transitionable over the patient cannula from a retracted position in which the patient end is exposed, to an extended position in which the patient end is shielded by at least a portion of the shield. At least a portion of the flash chamber is visible through an observation window or a transparent or translucent portion of the shield when the shield is retracted.
