From Wired :
The crowd is getting ugly. Soldiers roll up in a Hummer. Suddenly, the whole right half of your body is screaming in agony. You feel like you’ve been dipped in molten lava. You almost faint from shock and pain, but instead you stumble backwards — and then start running. To your surprise, everyone else is running too. In a few seconds, the street is completely empty.
You’ve just been hit with a new nonlethal weapon that has been certified for use in Iraq — even though critics argue there may be unforeseen effects.
According to documents obtained for Wired News under federal sunshine laws, the Air Force’s Active Denial System, or ADS, has been certified safe after lengthy tests by military scientists in the lab and in war games.
The ADS shoots a beam of millimeters waves, which are longer in wavelength than x-rays but shorter than microwaves — 94 GHz (= 3 mm wavelength) compared to 2.45 GHz (= 12 cm wavelength) in a standard microwave oven.
The longer waves are thought to limit the effects of the radiation. If used properly, ADS will produce no lasting adverse affects, the military argues.
Documents acquired for Wired News using the Freedom of Information Act claim that most of the radiation (83 percent) is instantly absorbed by the top layer of the skin, heating it rapidly.
The beam produces what experimenters call the “Goodbye effect,” or “prompt and highly motivated escape behavior.” In human tests, most subjects reached their pain threshold within 3 seconds, and none of the subjects could endure more than 5 seconds.