SHIELD_A is a powerful full 3D graphical application for the evaluation of the protection of structures from direct lightning strokes using the Rolling Sphere method. SHIELD is based on analytical model that consider vertical and lateral direct lightning strokes, and is then suitable for special structures of any height and shape.

Unlike SHIELD, SHIELD_A can also consider structures with significant protrusions, for instance wind towers, and has been developed mainly for lightning specialists. In essence, SHIELD_A was developed for all applications where SHIELD cannot be used, and is intended to be complementary to SHIELD.