An intumescent tape that expands in a fire to seal door frames and glazing applications to help prevent the passage of fire, smoke and toxic gases. Designed to seal the air space between doors and frames and for glazing fire-resistant glass to help prevent the passage of smoke and flames in the event of a fire. When exposed to heat such as would occur in a fire, the material expands to seal the gap and forms a char to deter the spread of a fire and to help prevent noxious gases, flames, or other by-products that may be produced in a fire.