Residual Foam Fire Retardant from a House Fire

This is an area of residual foam fire retardant in this home. This was from an environmental tapelift collected in a home before remediation from a house fire. The fire in this case was an attic fire that was contained just after it had burned into the living space and breached the roof. Foam was used to control and kill the fire. As the water evaporates from the foam this globular pattern is left.