Singlet Delta Oxygen Airflow Sterilization for Building Protection

Directed Energy Solutions (DES) proposes to design, fabricate, and test a basic prototype decontamination device for protecting buildings from chemical and biological weapons attack and the general enhancement of indoor air quality. The decontamination device generates metastable singlet delta oxygen (SDO), O2 (a1Δ), a strong oxidant of biological and chemical pathogens, from direct optical excitation of oxygen in a building’s heating, ventilation, and air conditioning (HVAC) system. The principal device components consist of an oxygen source (air), a commercially available optical excitation light source, and a multi-pass optical cell. The device is integrated into building ductwork to treat ambient air in situ as it passes through the HVAC system. Advantages of the device system include: (1) use of non-hazardous SDO as a proven oxidant; (2) quick and permanent destruction of the chemical or biological agent; (3) potential universal utility so the specific chemical or biological agent need not be known; (4) use of no toxic chemicals such as ozone, ethylene dioxide, or chlorine dioxide; (5) production of no toxic residuals such as ozone; (6) operation in both standby (routine purification) and high-power (attack protection) modes; (7) operation under minimum pressure drop; (8) use of durable and efficient off-the-shelf components with “set-and-forget” operation and no personnel training; and (9) no requirement to bring in additional fresh air with the associated expense of heating/cooling that air. During Phase I of this research project, DES demonstrated efficient SDO production from direct optical excitation of a flowing stream of oxygen. Measurements of the SDO reaction with an HD (chemical agent) simulant demonstrated the effectiveness of SDO against this simulant. During Phase II, a working prototype decontamination device will be developed, and this device will be tested against chemical and biological simulants for performance verification. Quantitative effectiveness data for SDO against biological and chemical species will be obtained. The optimized prototype design developed during Phase II will be ready for commercialization during Phase III. The commercial application of this device (Singlet Delta Oxygen Airflow Sterilization for Building Protection) has been assessed by DES and Foresight Science and Technology. The recommended applications include airflow sterilization of biologicals and oxidation of chemicals (including complete oxidation of volatile organic compounds to water and carbon dioxide) in homes and commercial/government office buildings and hospitals. Medical equipment sterilization also is a potential commercial application.