In a series of tests still underway at the Army's Aberdeen Proving Ground, INL researchers have been using ultraviolet-wavelength lasers to scrub surfaces clean of sulfur mustard gas and VX, a nerve agent. The tests have proved successful so far, even on complex, porous surfaces like concrete.
Lasers can degrade weapons like VX in two ways: photochemically or photothermally. In photochemical decomposition, high-energy laser photons blast apart chemical bonds, slicing the agent into pieces. In photothermal decomposition, photons heat up the target surface enough to speed along natural degradation reactions. In some cases, the intense heat by itself can cause contaminant molecules to fall apart.
Knowing how chemical contaminants fall apart is key, because some of the elements resulting from their degradation products can themselves be hazardous. But according to Fox, the tests look good in this regard, too. "The lasers are showing neutralization of the agent without generation of dangerous byproducts," he says.
And even if they're not used to degrade VX or other agents, lasers could still be helpful in cleanup scenarios. Laser light could blast nasty chemicals off a wall, for example, and an integrated vacuum system could suck them up.
Fox and his team are adapting an established technology. Lasers have been used in cleanup capacities for more than a decade. Dentists employ them to kill periodontal bacteria and quash mouth infections. Doctors use them to remove tattoos. And lasers have recently become a common tool to restore precious artwork.
Laser technology has other commercial applications. Some cleanup and restoration firms are already using lasers to scrub soot off buildin
|Contact: John Verrico|
US Department of Homeland Security - Science and Technology