Designed to prevent the spread of fire, smoke and noxious gas, 3M™ fire barrier sealant IC 15WB+ is a one-part, gun-grade, latex based, intumescent firestop sealant. This firestop sealant provides up to three hour fire protection in accordance with ASTM E 814 (UL 1479) and CAN/ULC S115. In addition, this product is fire-resistance tested for static construction joint systems in accordance with ASTM E 1966 (UL 2079). This sealant has been formulated to form a monolithic firestop seal that also helps minimize sound transfer, acting as a barrier to airborne sound transmission (STC-Rating of 54 when tested in a STC 54-rated wall assembly).