The video is dramatic. Five pounds of explosives detonate beneath a blue station wagon, engulfing the car in a cloud of smoke and debris. The vehicle is all but destroyed, but its two occupants — test dummies dubbed Thelma and Louise — are unscathed.

The material that muffled the explosion and promises to add a measure of safety to a world challenged by terrorists is focusing attention on an upstart company called BlastGard International Inc. Though it has yet to turn a profit, the Clearwater, Fla., company is winning awards and contracts with municipal agencies and the military.