Allegro 9911-20S Saran™ Maintenance Free Hood With the same features as our 9910-D, the Maintenance Free Saran Hood offers effective protection against a broader range of chemicals. It is made of Tyvek fabric that is laminated with saran to offer zero permeability to air and moisture, providing total protection against hazardous materials. The seams are heat tape sealed to form a liquid and gas-tight seal. It is ideal for acid handling, tank cleaning, agricultural pesticide handling, asbestos abatement, chemical handling and hazardous waste management. NIOSH approved.