long as the beam is applied, at a rate dictated by the target's material and distance from the transmitter, along with the beam's frequency and power level set by the operator. Most human test subjects reached their pain threshold within 3 seconds, and none could endure more than 5 seconds. A spokesman for the Air Force Research Laboratory described his experience as a test subject for the system: For the first millisecond, it just felt like the skin was warming up. Then it got warmer and warmer and you felt like it was on fire. ... As soon as you're away from that beam your skin returns to normal and there is no pain. Like all focused energy, the beam will irradiate all matter in the targeted area, including everything beyond/behind it that is not shielded, with no possible discrimination between individuals, objects or materials. Anyone incapable of leaving the target area (e.g., physically handicapped, infants, incapacitated, trapped, etc.) would continue to receive radiation until the operator turned off the beam. Reflective materials such as aluminum cooking foil should reflect this radiation and could be used to make clothing that would be protective against this radiation. Following approximately ten thousand test exposures of volunteers to ADS beams, a Penn State Human Effects Advisory Panel (HEAP) concluded that ADS is a non-lethal weapon that has a high probability of effectiveness with a low probability of injury: no significant effects for wearers of contact lenses or other eyewear (including night vision goggles) normal skin applications, such as cosmetics, have little effect on ADSʼs interaction with skin no age-related differences in response to ADS exposures no effect on the male reproduction system damage was the occurrence of pea-sized blisters in less than 0.1% of the exposures (6 of 10,000 exposures). In April 2007, one airman in an ADS test was overdosed and received second-degree burns on both legs, and was treated in a hospital for two days. There was also one laboratory accident in 1999 that resulted in a small second-degree burn. Safety studies Many possible long-term effects have been studied, with the conclusion that no long-term effects are likely at the exposure levels studied. However, overexposures of either operators or targets may cause thermal injury. According to an official military assessment, "In the event of an overexposure to a power density sufficient to produce thermal injury, there is an extremely low probability