title: Measured performance of filtration and ventilation systems for fine and ultrafine particles and ozone in an unoccupied modern California house.
abstract: This study evaluated nine ventilation and filtration systems in an unoccupied 2006 house located 250 m downwind of the I-80 freeway in Sacramento, California. Systems were evaluated for reducing indoor concentrations of outdoor particles in summer and fall/winter, ozone in summer, and particles from stir-fry cooking. Air exchange rate was measured continuously. Energy use was estimated for year-round operation in California. Exhaust ventilation without enhanced filtration provided indoor PM2.5that was 70% lower than outdoors. Supply ventilation with MERV13 filtration provided slightly less protection, whereas supply MERV16 filtration reduced PM2.5by 97-98% relative to outdoors. Supply filtration systems used little energy but provided no benefits for indoor-generated particles. Systems with MERV13-16 filter in the recirculating heating and cooling unit (FAU) operating continuously or 20 min/h reduced PM2.5by 93-98%. Across all systems, removal percentages were higher for ultrafine particles and lower for black carbon, relative to PM2.5. Indoor ozone was 3-4% of outdoors for all systems except an electronic air cleaner that produced ozone. Filtration via the FAU or portable filtration units lowered PM2.5by 25-75% when operated over the hour following cooking. The energy for year-round operation of FAU filtration with an efficient blower motor was estimated at 600 kWh/year.
authors.affiliation: Indoor Environment Group, Whole Building Systems Department, Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Singer
authors.affiliation: Indoor Environment Group, Whole Building Systems Department, Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: W W
authors.initials: WW
authors.lastname: Delp
authors.affiliation: Grid Integration Group, Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Black
authors.affiliation: Indoor Environment Group, Whole Building Systems Department, Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: I S
authors.initials: IS
authors.lastname: Walker
mesh_terms: D061808:Air Filters; D016902:Air Pollution, Indoor / Q000032:analysis*; D002140:California; D003296:Cooking; D004784:Environmental Monitoring / Q000379:methods; D006798:Housing; D006801:Humans; D010126:Ozone / Q000032:analysis*; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D012621:Seasons; D014691:Ventilation / Q000379:methods / Q000592:standards*
chemical_list: D052638:Particulate Matter; D010126:Ozone
keywords: 
  PM
  2.5
  ; black carbon; residential filtration; residential ventilation; ultrafine particles