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Cooking and cooking burners emit pollutants that can adversely affect indoor air quality in residences and significantly impact occupant health. Effective kitchen exhaust ventilation can reduce exposure to cooking-related air pollutants as an enabling step to healthier, low-energy homes. This report identifies barriers to the widespread adoption of kitchen exhaust ventilation technologies and practice and proposes a suite of strategies to overcome these barriers.

Whole-house ventilation systems are becoming commonplace in new construction, remodeling/renovation, and weatherization projects, driven by combinations of specific requirements for indoor air quality (IAQ), health, and compliance with standards, such as ASHRAE 62.2. At the same time we wish to reduce the energy use in homes and therefore minimize the energy used to provide ventilation. This study examined several approaches to reducing the energy requirements of providing acceptable IAQ in residential buildings. Two approaches were taken.

The goal of this study was to develop a Residential Integrated Ventilation Controller (RIVEC) to reduce the energy impact of required mechanical ventilation by 20%, maintain or improve indoor air quality and provide demand response benefits. This represents potential energy savings of about 140 GWh of electricity and 83 million therms of natural gas as well as proportional peak savings in California.

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy.

The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands.

Capture efficiency (CE) of exhaust from a natural gas cooking range was quantified for three  common designs of residential range hoods in laboratory experiments: (A) microwave exhaust combination; (B) short hood with grease-screen-covered air inlet at bottom; and (C) deep, open hood exhausting at top. Devices were evaluated at varying installation heights, at highest and lowest fan settings, and with the hood installed 15 cm away from back wall with intent to improve CE for front burners.

This study assessed the performance of seven new residential cooking exhaust hoods representing common U.S. designs. Laboratory tests were conducted to determine fan curves relating airflow to duct static pressure, sound levels, and exhaust gas capture efficiency for front and back cooktop burners and the oven. Airflow rate sensitivity to duct flow resistance was higher for axial fan devices than for centrifugal fan devices. Pollutant capture efficiency (CE) ranged from <15% to >98%, varying across hoods and with airflow and burner position for each hood.

The performance metrics of airflow, sound, and combustion product capture efficiency (CE) were measured for a convenience sample of fifteen cooking exhaust devices, as installed in residences. Results were analyzed to quantify the impact of various device- and installation-dependent parameters on CE. Measured maximum airflows were 70% or lower than values noted on product literature for 10 of the devices.

The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics.

Cooking and cooking burners emit pollutants that can adversely affect indoor air quality in residences and significantly impact occupant health. Effective kitchen exhaust ventilation can reduce exposure to cooking-related air pollutants as an enabling step to healthier, low-energy homes. This report identifies barriers to the widespread adoption of kitchen exhaust ventilation technologies and practice and proposes a suite of strategies to overcome these barriers.