1. Purpose
2. Product Scope
3. General Guidelines for Developing Fan Sound
    Ratings
    3.1 Definitions
    3.2 Rating development
    3.3 Similarity
    3.4 Rating methods
    3.5 Published sound ratings
4. Check Test
    4.1 General
    4.2 Check test tolerances
Annex A. Electronic Catalogs (Normative)
    A.1 Introduction
    A.2 Scope
    A.3 Allowable performance modifications
    A.4 Required qualifying statements
Annex B. Method of Presenting Sound Ratings in Spherical
         Sones (Normative)
    B.1 Hemispherical sones and spherical sones
    B.2 Presentation of values
    B.3 Calculation of loudness in spherical sones
Annex C. Additional Requirements for the Sound Performance
         Licensing of Air Curtain Units (Normative)