| Question | Answer |
| Body humidity | absolute humidity in a volume of gas saturated at the body temperature of 37°C; equivalent to 43.8 mg/L |
| Hypothermia | abnormal endangers condition in which the temperature of the body is below 32°C, usually caused by prolonged exposure to cold |
| Heat and moisture exchangers (HMEs) | devices that capture exhaled heat and moisture to warm and humidify the next inspiration |
| Hygroscopic | attracting or absorbing moisture from the air |
| Hygrometer | instrument that directly measures relative humidity of the atmosphere or the portion of water in a specific gas or gas mixture, without extracting moisture |
| American society For Testing Materials | nongovernment agency that establishes performance standards for various equipment and materials |
| Servo controlled heating system | in a humidifier, a heating unit that monitors the temperature of gas delivered to the patient, adjusting the power to the heater on the difference between temperature setting and the temperature monitored by the thermistor probe placed downstream from th |
| International Organization for Standardization (ISO) | nongovernment agency that sets standards for various technical equipment and procedures |
| Inspissated | (of a fluid) thickened or hardened through the absorption or evaporation of the liquid portion, as can occur with respiratory secretions when the upper airway is bypassed |
| Baffling | process of removing large water particles from suspension and a jet nebulizer so that the particles entering the patient’s airway are of a uniform therapeutic size |
| Ultrasonic nebulizer | humidifier in which an electric signal is used to produce high frequency vibrations in a container of fluid; the vibrations break up the fluid into aerosol particles |
| Hydrophobic | fear of water, or not letting water pass through a membrane |
| Nebulizer | device that produces an aerosol suspension of liquid particles in a gaseous medium using baffling to control particle size |
| Piezoelectric Crystal | transducer capable of converting electrical energy into the physical energy of high frequency vibrations |
| Isothermic Saturation Boundary (ISB) | The point in the lungs where the inspired gas achieves BTPS (body temperature pressure saturated) |
| |
