Joints of duct methods shall be designed significantly airtight by way of tapes, mastics, liquid sealants, gasketing or other authorized closure units. Closure units applied with rigid fibrous glass ducts shall comply with UL181A and shall be marked181A-P for force-delicate tape, 181A-M for mastic or 181 A-H for warmth-delicate tape. https://ericz357qpo7.tokka-blog.com/profile