scope:

1.1 These requirements apply to air dispersion system materials for use in accordance with the following Installation Codes:

1. a) Standard of the National Fire Protection Association for the Installation of Air-Conditioning and Ventilating Systems, NFPA No. 90A;
2. b) Standard of the National Fire Protection Association for the Installation of Warm Air Heating and Air-Conditioning Systems, NFPA No. 90B;
3. c) The International Mechanical Code® (IMC); and
4. d) The Uniform Mechanical Code^TM (UMC).

1.2 The air dispersion system materials covered by these requirements include preformed lengths of fabric or non-fabric products intended to convey and distribute air.

1.3 These air dispersion system materials are intended to be limited for use in air handling systems in exposed locations operating under positive pressure.

Exception: Air dispersion systems that have been tested to Section 10A (Collapse Test) and labeled with the rated negative pressure are not limited to operating under positive pressure.

1.4 These requirements do not intend to address the joints between sections of air dispersion system materials or end connections.