Goggle for protecting eyes with movable single-eye lenses and methods for using the goggle

A goggle comprising a single-eye lenses, a frame, a lens-retention mechanism and an adjustment mechanism wherein the single-eye lenses can be selectively moved relative to the frame to at least two different positions defining substantially different levels of air flow between the single-eye lenses and frame while maintaining the single-eye lenses in front of a user's eyes, and retained at each position. In certain embodiments, one position is defined by substantially all of the single-eye lenses periphery contacting the frame to substantially form a seal. Other positions are defined by substantially all of the lens periphery not contacting the frame wherein ambient air is allowed to flow uninhibited across the inside surface of the single-eye lenses. In certain embodiments, the lens-retention mechanism comprises a post and detent, while the adjustment mechanism comprises various mechanisms, for example a rack and pinion, a lever, or a rack and pawl that biases the single-eye lenses to one of the other positions. The adjustment and lens-retention mechanisms may be the same mechanism.