30 CFR §7.22

The following definitions apply in this subpart: Brattice cloth. A curtain of jute, plastic, or similar material used to control or direct ventilating air. Denier. A unit of yarn size indicating the fineness of fiber of material based on the number of grams in a length of 9,000 meters. Film. A sheet of flexible material applied to a scrim by pressure, temperature, adhesion, or other method. Scrim. A substrate material of plastic or fabric laminated between or coated with a film. Ventilation tubing. Rigid or flexible tubing used to convey ventilating air.