Patent ID: 8234722

Claim:
A protective covering for draping over a head unit to provide a sterile barrier between a user and an external environment, said protective covering comprising: a flaccid shroud including a filter section for filtering air entering the shroud from the external environment; a face shield formed of a flexible and transparent material and including a top portion, a bottom portion, and a sealing perimeter, said shroud sealed to said face shield along said sealing perimeter; a pair of lower mounting elements disposed on said face shield along said bottom portion of said face shield; and an upper mounting element disposed on said face shield along said top portion of said face shield, said upper and lower mounting elements defining three mounting locations at which said face shield is mounted to the head unit; said three mounting locations providing said face shield with a first radius of curvature along said bottom portion when said face shield is mounted to the head unit using said lower mounting elements and a second radius of curvature along said top portion when said face shield is mounted to the head unit using said upper mounting element, said first radius of curvature and said second radius of curvature being disposed in parallel planes, said first radius of curvature being smaller than said second radius of curvature to reduce glare directed toward the eyes of the user.