The objective of this investigation was to develop a sprayable ambient curing polymide foam for application to mine passageways. The first phase involved development of ambient cure foam formulations, evaluation of foam properties, selection of appropriate spray equipment, and test samples. The second phase involved development of continuous spray application, demonstration of reproducibility of properties, and spray application on a vertical surface. The program resulted in an ambient cure polyimide foam that can be dispensed by conventional spray equipment and that has excellent fire resistance and low flame spread. This composition can serve as the basis for the development of a practical, relatively low-cost, fire-resistent foam for mine applications.