UL CSDS Proposal
Published Date: February 24, 2017
Last Revision: December 29, 2021
Scope
001810-000000-0000001 Scope
1.1 These requirements apply to materials for the fabrication of air duct and air connector systems for use in accordance with the International Mechanical Code (IMC), International Residential Code (IRC), and Uniform Mechanical Code (UMC), Standards of the National Fire Protection Association for the Installation of Air-Conditioning and Ventilating Systems, NFPA No. 90A, and the Installation of Warm Air Heating and Air-Conditioning Systems, NFPA No. 90B.
1.2 The air ducts and air connectors covered by these requirements include preformed lengths of flexible or rigid ducts, materials in the form of boards for field fabrication of lengths of rigid ducts, and preformed flexible air connectors.
1.3 For the purpose of these requirements, air ducts and air connectors are classified as follows:
Class 0 – Air ducts and air connectors having surface burning characteristics of zero.
Class 1 – Air ducts and air connectors having a flame-spread index of not over 25 without evidence of continued progressive combustion and a smoke-developed index of not over 50.
Summary of Topics b0181_11_20170224_sum.htmlSubject 181
Bulletin Dated: February 24, 2017
SUMMARY OF TOPICS
The following is being proposed:
1. Reaffirmation and Continuance of the Eleventh Edition of the Standard for Safety for Factory-Made Air Ducts and Connectors, UL 181, as an American National Standard
Back to Standard 181, Edition 11