THE DEFINITIVE GUIDE TO GLASSCLOTH INSULATION

Joints of duct programs shall be produced substantially airtight through tapes, mastics, liquid sealants, gasketing or other permitted closure devices. Closure units used with rigid fibrous glass ducts shall comply with UL181A and shall be marked181A-P for force-sensitive tape, 181A-M for mastic or 181 A-H for heat-delicate tape. Closure units util