PROBLEM TO BE SOLVED: To provide a method of actuating a passively operated shielding needle assembly that provides a guide useful in locating an ideal puncture site.SOLUTION: A method comprises: providing a needle assembly comprising a hub including a needle cannula with a puncture tip extending from a forward end thereof, the hub at least partially disposed within a shield member and biased toward a position in which the puncture tip of the needle cannula is encompassed within the shield member, the needle assembly further comprising a pivotal lever connected to an injection barrel, the pivotal lever including a front portion adjacent to the needle cannula and a first engagement with the hub for maintaining the hub against the bias with the puncture tip exposed from a forward end of the shield member and inserting the puncture tip of the needle cannula through a surface such that the pivotal lever contacts the surface and causes the lever to pivot with respect to the shield member thereby releasing the first engagement between the lever and the hub.
