Exposure to certain harmful high frequencies, do you realize how often this can happen in your everyday life? You may be surprised to know that many department stores use the ultra high frequencies for theft control. Many of these frequencies can have major affects on people especially children. Ring tones on cell phones can use these technologies. Some ring tone frequencies are outside the adult hearing ranges, yet teenager's can hear them fine when their cell phone rings. We will cover many of the uses and affects of ultra high frequencies.