A protective breathing mask assembly comprises a face mask portion 10 having a brow support 5 at the top thereof which, in use, extends around the brow of the wearer, and a face seal 6 which extends around the back edge of the mask portion 10 so as, in use, to engage around the sides of the wearer's face to prevent the ingress of material into the mask portion. The mask assembly further includes a rear of head strap 4 which extends between the ends of the brow support 5, in use, around the back of the wearer's head. A crown strap 2 is connected to opposing sides of the mask assembly so as, in use, to extend across the top of the wearer's head in opposing relation to the face seal 6, thereby pulling the face seal up against the wearer's face. A head panel 1 extends between and is connected to the crown strap 2 and the rear of head strap 4 so as to be diametrically opposite to the face seal 6, and a hood 11 extends from the brow support 5 rearward over the head panel 1 so as, in use, to enclose the wearer's head and protect against exposure to hazardous material whereby, in use, the head panel 1 engages the top of the wearer's head so as to properly locate the assembly on the wearer's head.