These revisions to ANSI/UL 181A include the following changes in requirements:
Clarify construction material requirements for mastic closure systems for use with rigid fiberglass air ducts, Part III Section 26
Correct UL 181 test reference to specify the burning test, Section 35
Add the requirement for the minimum application width to be included as part of the installation instructions, Section 37
Revise the mesh requirement in the Adhesion Test on the mastic system to comply with the Standard Test Method for Adhesion-in-Peel of Elastomeric Joint Sealants, ASTM C794, Section 29
Revise ASTM D3654 reference