Julie Kalista
Online Editor

The Active Denial System, a non-lethal weapon, repels human targets by projecting a beam of energy that creates an intolerable heating sensation on the skin. (Photo Credit: Airman 1st Class Gina Chiaverotti)
In the years following, the Army began to develop less-lethal means for crowd-control and riot tactics. One of these more recent, less-lethal means is the Active Denial System, a long-range, non-lethal weapon that shoots an invisible beam penetrating the skin at 1/64 of an inch, equivalent to about three sheets of paper.

The beam creates a heating sensation on the skin, similar to touching a light bulb that has been on for awhile. But, unlike a hot light bulb, the weapon will not cause rapid burning because of the beam's shallow penetration. ADS operates at 95-GHz mm radio frequency wavelength that moves at the speed of light. According to reports, a 2-sec. burst heats the skin to 130°F (50°C). A person would have to be in the beam for 250 seconds for it to burn the skin. Built-in safety features include a bore-sighted sensor that lets operators see entire beam paths and target areas.

Experts have determined there are no long-term health effects associated with ADS, based on tests including more than 600 volunteers and 10,000 exposures. However, volunteers removed glasses, contact lenses, and any metal objects that could cause hot-spots, raising eyebrows about ADS' safety in the field when no precautions are taken. And, despite the fact that the experts have proven there is a less than 1/10 of a percent chance of even a minor injury, a study published in Health Physics indicates exposure to 2W/cm2 for three seconds could damage the cornea of rhesus monkeys.

Two weapons systems have already been created, ADS System 0 and ADS System 1. A modular system (ADS System 2) is currently being developed and is scheduled to be completed in June of this year. The ADS system 2 is designed to operate in higher temperatures and will operate at fixed sites or on the back of trucks. The 820th SFG at the Moody Air Force Base in Georgia is currently conducting a series of combat scenarios to determine potential effectiveness in a deployed environment.

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