** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** AGAINST A BACKDROP OF HIGHER GLOBAL ENERGY COSTS, THE HEAT STRESS CAUSED BY A WARMING CLIMATE AND THE HOUSING OF HIGH MILK-PRODUCING DAIRY CATTLE CREATES A SIGNIFICANT OPPORTUNITY TO INVESTIGATE COST-EFFECTIVE APPROACHES TO VENTILATING AND COOLING COW BARNS. CURRENT APPROACHES INVOLVE LARGE NUMBERS OF FANS THAT USE MORE ENERGY AND EMIT HIGHER LEVELS OF GREENHOUSE GASES (GHG) THAN TRADITIONAL, NATURALLY VENTILATED BARNS AND OFTEN FAIL TO EFFICIENTLY SUPPLY AN OPTIMAL AIRFLOW THROUGH THE COW'S RESTING AREA. WE PROPOSE A UNIQUELY ENGINEERED POSITIVE PRESSURE PRECISION VENTILATION (PPPV) SYSTEM THAT ADDRESSES THESE CONCERNS BY PROVIDING THE AIRFLOW REQUIRED TO COOL THE ANIMALS WHILE USING LESS POWER AND EMITTING LOWER LEVELS OF GHG. THAT IS, THE PROPOSED SYSTEM IS SPECIFICALLY DESIGNED TO DELIVER FRESH AIR JETS AT DESIRED SPEEDS TO EVERY COW IN EVERY STALL AND TO OTHER TARGETED AREAS INSIDE A DAIRY BARN. A FULL-SCALE COMPUTER MODEL WITH HEAT AND MASS TRANSFER COMPONENTS WOULD BE USED TO REFINE THE DESIGN OF A PPPV SYSTEM. THE REFINED SYSTEM WOULD THEN BE FIELD TESTED, AND ITS PERFORMANCE COMPARED WITH THAT OF TRADITIONAL VENTILATION SYSTEMS. ANIMAL-RELATED OUTCOMES, INCLUDING LYING BEHAVIOR, CORE BODY TEMPERATURE, RUMINATION, RESPIRATION RATE, AND PANTING, WOULD BE RECORDED DURING THE SUMMER. AIR SAMPLES FOR THE MEASUREMENT OF POLLUTANTS WOULD BE COLLECTED DURING WARM, HOT, AND COOL WEATHER CONDITIONS, AND THE OCCUPATIONAL HEALTH RISKS OF EXPOSURE TO THESE POLLUTANTS AT REDUCED VENTILATION RATES WOULD BE ASSESSED. ALSO, VENTILATION-RELATED GHG EMISSIONS AND THE OPERATIONAL COST OF EACH VENTILATION SYSTEM WOULD BE CALCULATED AND COMPARED TO DETERMINE THE EXPECTED RETURN ON INVESTMENT.