A novel method and device for the destruction of nitrous oxide in gases such as those resulting from exhaled breath during dental, medical, and veterinary procedures are described. The method employs processing steps including the collection of gases containing constituents such as water vapor, carbon dioxide, oxygen, nitrogen, and nitrous oxide from exhaled breath or from ambient room air, optional removal of moisture from the collected gas, catalytic decomposition of nitrous oxide gas to nitrogen and oxygen, heat exchange to reduce high temperatures in gases exiting the reactor, and sorbents to remove traces of reaction byproducts. Instrumentation and controls are employed to monitor and regulate temperatures, pressures, gas compositions, and flow rates while also providing measures to automatically shut down in the event of off-nominal conditions. The method and device are capable of operating with variable anesthetic or patient exhaled breath flow rates while inducing no significant pressure or vacuum on the patient as they exhale. The method is carried out in a compact device suitable for operation in dental offices, hospitals, and other locations where nitrous oxide is administered as an anesthetic.
