3M FireDam Spray 100 is a flexible, sprayable, water-based coating. 3M FireDam Spray 100 dries in ambient conditions to form a flexible seal. 3M FireDam Spray 100 firestops head-of-wall joints, floors joints, penetration seals, and perimeter joints (curtain wall joints). 3M FireDam Spray 100, when installed properly, will control the transmission of fire, heat and smoke before, during and after exposure to fire.