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1 Sound Barrier System 128 Research and Development Overview D.Moses Consulting has joined forces with Compound Security Systems of the U.K., our manufacturer of the SBS 128 Sounder high decibel level acoustic device. This product is an extension of research and development initiated in the design of the MK 4 Mosquito which is marketed and sold extensively around the world. 2 SBS 128 Sounder Research and Development Overview As a result of the MK 4 success in addressing crowd control, an iterative design process of providing a higher sound pressure level (measured in decibels) device would be required as a deterrent in higher threat scenarios. This process resulted in additional design requirements incorporated into the SBS 128 db unit, which has been field engineering tested and evaluated. 3 SBS 128 Operational Design Features Compound Security Systems has provided the following operational design features to be incorporated into the SBS 128 Sounder Unit for our review and understanding. 4 SBS 128 Sounder System Compound Security’s Overview The unit produces a sound level of 128dB @ 3.3Ft, the acoustic signal has been especially designed to be extremely unpleasant and to induce ringing of the ears, dizziness and in some individuals, even headache and nausea. Note: The audio file has been extensively re-worked to extend both the operating range and unpleasant effects from the original prototype with the assistance of a world-renowned professor of acoustics. The device has been designed to withstand extremes of both temperature and humidity and using solid-state transducers to operate at high power efficiency for extended periods. 5 SBS 128 Sounder Unit SBS 128 Enclosure The enclosure has been designed to resist a high level of attack, being manufactured in high-grade 12-gauge stainless steel with welded seams and security fasteners used throughout. Cable entry to the rear via IP rated stainless cable gland. 6 SBS 128 Power Requirements The unit is designed to run from 110 to 240vac. Current consumption at 100 watts is in the range of 3 amps per unit. Rated power 100 watts Thermal protection has been included to prevent damage to the unit at the extreme temperatures that some units may be exposed to. This is achieved by automatically reducing the duration of activation on detection. 7 SBS 128 Transducers (Speakers) An array of 5 by 3 high performance piezo transducers will be utilized. Note: The initial prototype used an array of 2 by 3 elements; the manufactured unit uses a larger array to extend the life of the transducers as well as increasing the sound coverage area. 8 SBS 128 Control The SBS 128 is radio linked to OPTEX HX40 dual element passive infrared detectors. These detectors are regarded as some of the best commercial external detectors available with a high immunity to false activations from wild or domestic animals as well as market leading temperature compensation circuitry. 9 OPTEX HX40 Infrared Detectors 10 SBS 128 The detection pattern of the PIR is 85 degrees with a range of 40Ft. Recommended separation between units is 35 ft with an HX40 detector mounted at the center point. Each individual sounder is programmed to operate on activation of one or more selected detectors, which allows for both the sounder to the right and to the left to operate on activation of the detector mounted between them. Operating frequency 418Mhz at 10mw. 11 SBS 128 Sounders and OPTEX HX40 Infrared Detectors Installation Along Fence Line 12 Illustrated Area of SBS 128 Sounders and OPTEX HX40 Infrared Detectors Installation and Coverage 13 SBS 128 Time control There is an inbuilt real time clock within the sounder that can be programmed so that the unit will only operate between pre-set times over a 7-day period. The duration of activation after detection will be programmable from 1 to 60 minutes. The programming of the individual units is accomplished using a wireless hand held encrypted programming unit. Each sounder incorporates both a RF transmitter and receiver allowing the entire system to be disabled and enabled by use of the handheld controller. This is achieved without the requirement of a separate high-powered radio link as each unit receives commands from the adjacent unit and passes the instructions down the line. Guard Patrol Sounder Inhibit Transmitter An additional feature is a belt worn transmitter that will allow staff to walk the fence line without activating the devices. 14 Sound Barrier System 128 CONCEPTUAL DESIGN CRITERIA The conceptual design criteria, incorporated in the production of the SBS 128, provides a sound pressure level which human hearing would experience at the threshold of pain. Both physiological and psychological effects are non-lethal allowing for a nonconfrontational environment with a presumed threat. The urge to avoid and retreat results in a rapid and immediate response. This response by any individual or group acts as a deterrent, therefore preventing incursion into a predetermined and designated perimeter line of a secured area. To ensure the understanding of the SBS 128 operational design features as a complete system, a brief discussion of auditory acoustic noise transmission is warranted . The following pages simply explain auditory acoustic noise transmission, measuring noise level and establishing hearing threshold data, and physiological and psychological effects of high intensity noise levels on human performance. 15 In general, acoustics is the science/technology of sound, including its production, transmission and effects. Auditory Acoustic Noise Transmission Sound waves impinge on the outer ear and cause the ear drum to vibrate. Vibrations are conducted via a lever action of the middle-ear bones to the oval window, which activates the fluid-filled inner ear. Portions of nerve endings in the cochlea are selectively excited, and their outputs end in the brain for further interpretation. Physiology of Ear Noise Transmission 16 Physiological and Psychological Affects of High Intensity Noise Levels on Human Performance Our major objectives of testing and evaluating the SBS 128 as an acceptable alarm and warning device for non-confrontational human scenarios was accomplished. Identifying physiological and psychological affects on human exposure to decibel levels in excess of 125 db is considered an extreme hazard. The degree of pain and potential hearing loss is dependent on duration, intensity, and distance from the continuous and/or intermittent originating noise source. The following are examples of Physiological affects: The following are examples of Psychological affects: 1. Ear Pain 1. Reduced Speech Communication 2. Hearing Loss 2. Reduced Thought Processes 3. Nausea and Vomiting 3. Upgraded Reflex Response (Urge to Avoid or Escape) 4. Headache 4. Inability to Perform Simple Tasks 5. Abnormal Heart Rate 5. Vertigo 17 Measuring Noise Level and Establishing Hearing Threshold Data This example illustration, identifies the intensity level measured in decibels on the vertical scale at different frequencies (CPS) measured on the horizontal scale. Both threshold of hearing and threshold of pain for different venues, along with an optimum conversational speech envelope, is illustrated. This example illustrates Intensity Level (SPL) in Decibels at Different Frequencies. 18 Rapid and Immediate Urge to Avoid and Retreat 19 Summary • The inner ear has the ability to adapt to pure tone or loud sounds. However, it cannot adapt to the modulated tone and frequency variation of the SBS 128. • Hearing devices such as headphones and earplugs will muffle pure tone sounds of the SBS 128. However, the tone modulation causes physiological and psychological effects. • Intruders or would be criminals do not like to lose the ability to hear or see what is going on around them. • Studies show that 80% of criminal activity can be eliminated by sound and light. • In summary, the research and development of the Sound Barrier System 128 has proven to be a logical first line of defense in deterring any ground threat to company personnel, infrastructure, materials, and services. • When considering the mindset of those threats willing to destroy company assets, a nonconfrontational environment initiated by a high sound pressure noise level environment creates that change in mindset, resulting in the urge to rapidly and immediately retreat. 20 Conclusion In conclusion, any threat analysis scenario involving known threats, their location, timing and mindset, can best be treated in a non-lethal, non-confrontational environment. The advantage of the Sound Barrier System over other security systems is the ability to allow the human threat to cease and desist long before the need for additional security assets are required to eliminate a potential unsafe, unwanted event. In providing a non-confrontational environment initiated by an individual threat or group, the Sound Barrier System allows for safer preventive measures, wherein we believe liability is not an issue. Both friend and foe would easily refrain from contact within the environment created by this event. 21