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Chemists investigate how to 'scrub' chemical-contaminated buildings clean with lasers

Chemists at Idaho National Laboratory are researching how to use lasers to clean contaminated buildings after chemical attacks.

Chemists at Idaho National Laboratory are researching how to use lasers to clean contaminated buildings after chemical attacks.

Funded by the U.S. Department of Homeland Security's Science and Technology Directorate, the researchers say lasers could be a powerful tool when paired with water, penetrating the cracks and pores of a surface to turn water to steam and carry contaminants back to the surface for removal.

"It's a kind of laser steam-cleaning," chemist Bob Fox said in a statement.

Researchers first turned to lasers as a way to dispose of radioactive contamination after a dirty bomb. Now, they see lasers as useful for chemical-weapon decontamination.

The researchers have been conducting tests at the U.S. Army's Aberdeen Proving Ground, using ultraviolet-wavelength lasers to clean sulfur mustard gas and the nerve agent VX. So far, the tests have been a success, even on porous surfaces such as concrete.

Lasers can degrade agents like VX in two ways:

  • Photochemically, in which high-energy laser photons break apart the agent's chemical bonds.
  • Photothermally, in which laser photons speed up natural degradation reactions by heating up the target surface.

One danger is that some resulting components of chemical agents are themselves dangerous. But researchers say the process hasn't created any dangerous byproducts thus far.

The researchers also foresee using lasers to strip chemicals from a wall to be sucked up by an integrated vacuum system.

Currently, the process of cleaning up chemical-contaminated structures is difficult, costly and time-consuming, and relies on corrosive chemicals such as bleach.

Lasers are a natural answer: they are currently used to curb bacterial infections, remove tattoos and restore artwork. Even better, they can be automated, allowing technicians to perform work remotely, out of harm's way.

For now, the researchers say lasers are in proof-of-principle stage. But the U.S. government is surely keeping an eye on its progress.

Image: Neodymium-YAG laser/U.S. DHS

This post was originally published on Smartplanet.com