Florida Doctor Invents Cloth That Blocks Radiation.

Ronald DeMeo places a radioactive wafer about the size of a silver dollar on his desk and waves a handheld Geiger counter over it. The machine chatters wildly, the numbers on the readout spin upward and visitors instinctively lean back.

But when the Coral Gables doctor covers the disc, which is designed for materials testing and quite safe, with a thin piece of fabric, the numbers dive and the noise from the Geiger dips to a low growl.

It's an effective demonstration of Demron -- the radiation-blocking material of DeMeo's invention -- and one that his Coral Gables company, Radiation Shield Technologies, hopes will find a receptive audience in a post-9-11, security-conscious world.

The patented fabric -- just slightly thicker than denim -- is embedded with metal particles and other compounds capable of blocking X-rays, low-energy gamma rays and other types of nuclear emission that might be found anywhere from a doctor's office to the site of a dirty bomb blast.

The company had just under $1 million in sales last year, providing torso vests and full Demron suits to doctors and a specialized niche of first responders. But now RST is hoping to broaden its reach into the military market with the launch of Demron-W, which is also impervious to chemical and biological agents.

Wait until the tinfoil hat brigade hears about this stuff!