1.  Hoods shall have transparent movable sashes constructed of shatter-resistance, flame resistant material and capable of closing the entire front face.

_{ANSI/AIHA Z9.5-2003,}

_{8 CCR 5154.1(c)}

_{Good Practice per Stanford University}

2.  Vertical-rising sashes are preferred. If horizontal sashes are used, sash panels (horizontal sliding) must be 12 to 14 inches in width.

_{Good Practice per Stanford University}

Sashes may offer extra protection to lab workers since they can be positioned to act as a shield.

3.  A force of five pounds shall be sufficient to move vertically and/or horizontally moving doors and sashes.

_{ANSI/AIHA Z9.5-2003, 3.1.1}