Surgical helmet

摘要

The disclosed air filtration system filters both entering and exiting air. A primary structural element of the air filtration system is the unitary helmet member, which fits over the user's head. The unitary helmet member includes both a front aperture near the user's forehead and a rear aperture near the upper rear portion of the user's head. The unitary helmet member is blow-molded and therefore simple in construction. An interior channel connects the front aperture to the rear aperture, and a fan located over the rear aperture circulates air between these two apertures. A hood filter and a face shield fit over the unitary helmet member. The hood filter filters air passing through the rear aperture, and further filters air passing through a rear portion of the hood filter. Only the single fan is needed to draw air into the hood filter and remove air from the hood filter. The fan is placed over the rear aperture, thus distributing weight on the upper rear portion of the user's head to reduce stress and fatigue of the user. A secondary filter for added performance may be placed under the hood filter or over the fan inlet surface. A middle aperture located on the unitary helmet member between the front and rear apertures provides for a venting function to allow warm air to pass to the top of the user's head before exiting through the hood filter.