DOI: 10.5061/dryad.4mw6m90qj
title: Data from: Mechanical ventilation and indoor air quality in recently constructed homes in cool and humid climates of the U.S.

description: This dataset was collected as part of the Building America Ventilation and
 Indoor Air Quality (BAVIAQ) field study. The BAVIAQ study aimed to measure
 indoor air quality (IAQ) parameters, characterize ventilation equipment
 and other house and household characteristics, and actions that impact
 IAQ, with a focus on the role of whole-house mechanical ventilation
 (WHMV). This dataset was obtained from visits and monitoring in 32
 single-family homes constructed since 2013 in the cool and humid climate
 of Illinois. A total of 41 weeks of data were collected. These included
 one week of data collection in each home under the “as-found” condition of
 no WHMV, and a second week of data collection in nine homes, during which
 an exhaust fan was operated to provide WHMV. The dataset includes
 time-resolved measurements of CO2, PM2.5, formaldehyde, and radon at one
 or multiple indoor locations, and time-integrated samples of gravimetric
 PM2.5, NO2, NOx, and formaldehyde collected both indoors and outdoors.
 Occupants’ activities, including ventilation equipment usage, cooking,
 window opening, and other usage related to IAQ, were also monitored.
 Participants also provided household characteristics, practices
 influencing ventilation and pollutant sources, and self-reported
 satisfaction with air quality, thermal comfort, and other environmental
 factors. Building performance metrics were documented, including envelope
 and duct leakage, mechanical ventilation airflow rates, WHMV system type,
 controls, operational status, labeling, and compliance with ASHRAE
 62.2–2010. The dataset can be used to support research on IAQ impacts of
 WHMV systems, building performance, occupant behavior, and pollutant
 exposure in recently constructed, energy-efficient homes. It enables
 paired-condition comparisons, facilitates evaluation of ventilation
 standard compliance, and provides a foundation for examining the
 effectiveness of WHMV in reducing indoor pollutant levels.
description: <strong>Overview of the data
 collection</strong> The basic structure of the
 study was to characterize the mechanical ventilation equipment
 functionality in each house through observations and performance
 measurements, monitor ventilation equipment usage, and measure air quality
 parameters indoors and outdoors over weeklong periods. Data were also
 collected by asking occupants to provide information about the household,
 their practices related to ventilation and pollutant sources and controls,
 and their satisfaction with air quality, thermal comfort, and other
 environmental factors in the home. Homes were monitored for one week with
 their WHMV operating as-found. In a subset of homes, the WHMV was
 configured by the research team to meet the ASHRAE 62.2–2013 continuous
 ventilation requirement and monitored for a second week. Due to
 limitations in finding homes with operable WHMV, local exhaust fans were
 utilized to meet ASHRAE 62.2. Each study home was
 visited by a two-person field team at the start and end of each monitoring
 period. House and ventilation equipment characterization typically
 occurred during the first visit and included documenting the system
 configuration and as-found operational status. Observational data
 collected during the field team visits included ventilation equipment
 model numbers, filter ratings, filter location, type of cooking appliance,
 and other details. During this visit, the field team installed
 instrumentation to measure indoor and outdoor air quality parameters,
 operation of ventilation equipment, and the central forced air (CFA)
 system, use of the main cooking appliance, and the open-closed position of
 selected doors and windows. Two-week homes were visited between the weeks
 to collect and redeploy passive samplers, download data from some
 instruments, and change the WHMV equipment to meet ASHRAE 62.2. Air
 leakage of the building envelope and air distribution ducts of the CFA
 heating and cooling system typically occurred during the final visit. The
 team also asked the participant if they thought their home had a WHMV
 system and, if so, did they knew how to operate it.
 Participants were asked to partake in normal household
 activities, with the exception that windows and doors should not be used
 for natural ventilation, and no smoking of any kind should be done inside
 the home during the data collection period. Participants were asked to
 complete an activity log for each day of the monitoring period, designed
 to record actual occupancy as well as routine and intermittent activities
 that could affect IAQ. The study was reviewed and
 approved by the Central Institutional Review Board (IRB) of the U.S.
 Department of Energy. <strong>Eligibility and
 recruitment</strong> The study aimed to collect
 data in a sample of otherwise similar newly constructed single-family
 detached or attached homes being monitored with their WHMV in its as-found
 condition, and a subgroup of homes being monitored for a second week with
 their WHMV operating at the ASHRAE 62.2 2013 continuous ventilation
 requirement. The minimum eligibility criteria were that the home had to be
 constructed in 2013 or later and completed at least one year before data
 collection to reduce the potential impact of all materials in the home
 being very new (and potentially still in an initially higher emitting
 regime for formaldehyde) and occupants being too recently introduced to
 the house and its ventilation equipment. The goal was to study homes that
 were built to recent standards and with relatively new
 equipment. The main outreach method for recruitment was
 through semi-regular advertisements on the University of Illinois
 Urbana-Champaign’s faculty and staff weekly e-newsletter. A phone
 interview was conducted to screen homes for eligibility. To participate,
 they must have been newly constructed (2013 or later), single-family
 detached or attached homes, located in Illinois, be owner-occupied, and
 non-smoking. If a home was eligible, questions about the building
 characteristics and ventilation systems were asked over the phone.
 Participants were instructed that they would need to avoid opening
 exterior doors and windows during the monitoring period. All homes would
 participate for a minimum of one week with the WHMV system left in its
 current operating state (as-is). A subset of homes that had a venting
 range hood and multiple bathroom exhaust fans, of which the airflows could
 meet the ASHRAE 62.2-2013 continuous ventilation requirement, were invited
 to participate in an additional week of monitoring. During the second
 week, the bathroom exhaust fans were operated to meet the 62.2 airflow
 requirement, and the participants were informed not to modify them during
 the remaining monitoring period. Additional recruitment
 was done through mail postcards in the Champaign and Urbana areas.
 Eligible homes were identified using a mix of local online data sources,
 including building permits (https://data.ccrpc.org/dataset/building-permits), property tax records (https://champaignil.devnetwedge.com/), and real-estate websites. Word of mouth from existing participants enrolled in the study also played a role in recruiting new homes. <strong>Measuring and monitoring airflows and air leakage</strong> Airflows were measured for WHMV systems, bathroom and kitchen exhaust fans, and clothes dryers. To determine inputs and coefficients for the natural infiltration model, a Delta-Q test was conducted in each home to measure building envelope and duct leakage, and to determine envelope leakage flow coefficient (c) and exponent (n). Forced air heating and cooling system operation was monitored by deploying anemometers and TRH sensors at supply air registers. Exhaust fans were monitored by anemometers or motor on/off loggers. Cooking appliance usage was monitored by temperature sensors on the cooktop surface. Patio door, garage to house door, and main bedroom door status were recorded. Portable air cleaners, humidifiers, and other devices related to IAQ were monitored by plug load power meters. <strong>Air quality measurements</strong> Air quality measurements were conducted at both on-site outdoor and indoor locations. The devices used in this study for indoor and outdoor air quality measurements and their accuracy, deployment location are shown below. Measurement Device Parameters Accuracy(a) Res. Sampling locations Met OneE-Sampler Estimated PM2.5 by photometry;  Photometry: ± 10% to the gravimetric method, typical when K-factored to local particulate type (b). 5min  Outdoor Met One BT-645 Photometer Estimated PM2.5 by photometry ±5% traceable standard with 0.6 µm PSL, autozeroing function enabled to check baseline hourly(c) 1 min Indoor central AirVisual Pro Estimated PM2.5 by photometry, CO2, T, RH CO2: ±50ppm or 2% of reading(d) 10 sec–5min Indoor central; Master BR; Office, secondary bedroom, or family room Ogawa Passive Samplers NO2 and NOx Based on field validation(e): 7 d relative deviation of 3±2% NO2 at 11-37 ppb; 4±3% NOX at 16-85 ppb; 10±9% (NOX-NO2) at 4-56 ppb 1 wk Outdoor; indoor central Graywolf FM-801 HCHO ±4 ppb &lt;40 ppb, ±10% of reading ≥40 ppb 30 min Indoor central; Master BR SKC UMEx-100 Passive HCHO ±25%, exceeds OSHA requirements 1 wk Outdoor; Indoor Onset HOBO UX100-003, T, RH ±0.21 °C from 0 to 50 °C 1 min Outdoor, Indoor: master bedroom, master and secondary bathroom (U23); Laundry room (UX100-011); Central location, attic, basement (UX100-003); RadStar RS300 Radonshort-termrm &lt;10% deviation from 0.5 to 150 pCi/L 60 min Indoor: central and/or basement AccuStar Alpha Track Radon, long-term General within ±15% to ±30% when deployed in the field for periods ≥3 months 3–6 months Indoor: central and/or basement PEM Sampler PM2.5 by gravimetric mass Balance accuracy: 0.1µg 1 wk Indoor a. Based on manufacturer specifications unless otherwise noted.<br> b. We did not evaluate the K-factor for the device; thus, outdoor PM concentrations measured by MetOne need to be compared with local monitors and gravimetric mass results before using them for analysis<br> c. Cross checks between the indoor and outdoor MetOne units in the previous study showed close agreement. Therefore, no adjustment was applied to the indoor MetOne data in this dataset.<br> d. Co-location between AVP units found a good correlation in CO2 measurements.<br> e. Based on field validation in California reported by Singer et al. 2004.<br> f. The collected mass on a filter was determined as the difference in post and pre-exposure weights, and air concentrations were calculated using the sample volume calculated by the elapsed exposure time and sample airflow. See Quality Assurance sections for details <strong>Participant survey and daily activity log</strong> Before the field team visited the homes, participants were provided with and asked to respond to an online questionnaire that asked how they feel about their home environment and about the factors that can affect their IAQ. They were also asked about activities and product use and for information related to the home and household, including basic demographic and health-related questions. During the first visit, the field team provided participants with a printed activity log for each day of the monitoring period, designed to capture actual occupancy and routine and intermittent activities that could affect IAQ. This included prolonged opening of windows and doors, house cleaning, cooking, and burning candles. The log also had the occupant report periods of poor outdoor air quality, for example, from a nearby forest fire. <strong>Acknowledgements</strong> ICRT performed this work under contract to the Illinois Applied Research Institute, University of Illinois Urbana-Champaign (UIUC). ICRT moved from UIUC to the Champaign County Regional Planning Commission in July 2023. We acknowledge the contributions of former ICRT staff members J.S. (field work and instrumentation management) and S.G. (project management), who left before this date. We thank the residents who welcomed us into their homes during this project, and for working with us during the early days of the pandemic when home visits were more challenging to execute. We thank the UIUC School of Architecture and its students for producing floor plans at each site and the following for their contributions. E.W., co-conceived of the study, arranged funding, and managed the Building America program through which the study was implemented; L.B. helped administer the study for the Building America program; and both provided helpful input throughout the study development and data collection phases. R.M. program director for the Residential Energy Services Network, queried the rated homes database and provided records to assist with participant recruitment. Y.W. and A. J. helped to develop the dataset.
description: # Data from: Mechanical ventilation and indoor air quality in recently
 constructed homes in cool and humid climates of the U.S. Dataset DOI:
 [10.5061/dryad.4mw6m90qj](https://doi.org/10.5061/dryad.4mw6m90qj) ##
 Description of the data and file structure ### What is in the dataset? The
 dataset contains the most relevant information collected about the houses
 and household, their mechanical equipment, results of the participant
 survey, results of air leakage and airflow measurements at the homes,
 pollutant concentrations measured by time-integrated passive samplers
 inside and outside of the home, usage of cooktop and oven, external door
 and window open state, and time-series or air pollutants and environmental
 indicators measured within and outside of the houses. ## Files and
 variables ### Infiltration_Airflow This folder (Infiltration_Airflow.zip)
 contains time-resolved data of the calculated natural infiltration airflow
 during the measured week for each test home. The natural infiltration
 airflow was estimated using the single zone models described in the ASHRAE
 Fundamentals Handbook assuming no substantial window or door opening.
 Briefly, the total natural infiltration airflow is the sum of two
 independent vectors: stack flow(Qs) and wind flow (Qw). The stack flow is
 calculated using indoor and outdoor temperature difference and stack
 coefficient and pressure coefficient from air leakage test (DeltaQ); the
 wind flow is calculated using outdoor wind speed and coefficient from air
 leakage test.  There is one csv file for each measured home. There is also
 a specific readme file in the folder (Natural Infiltration - README) for
 more details. Missing data resulting from either an invalid flow
 measurement or unavailability of outdoor weather data were filled with
 “NA”. ##### Column naming and explanations: * WS Windspeed m/s; NOAA (10 m
 above ground) - TOUT Outdoor temperature from NOAA  / Fahrenheit * TIN
 Indoor temperature from TRH_GRL / Fahrenheit - T_diff TIN -TOUT  /
 Converted to Celsius before substraction * T_n T_diff ^n^ - Qs c*Cs*T_n *
 GU_m.s G*WS - Qw c*Cw*(s*U) ^2n^ * Q sqrt(Qs^2+Qw^2) in m^3^ - QCFM_Inf Q
 in CFM There is also a coefficient summary file summarize all the
 coefficient for each house used for the calculation: **Coefficient and
 explanations**: * G Windspeed multiplier - c Flow coefficient;  DeltaQ * n
 Pressure exponent; DeltaQ - Cs Stack cofficient * Cw Wind coefficient - S
 Shelter factor ### DeltaQ This folder (DeltaQ.zip) contains data about the
 DeltaQ test results for each home. There is one csv file containing the
 results for all 32 homes. Three homes (518, 536,544) did not get valid
 results for both pressurization and depressurization tests, the C values
 were imputed using n=0.65. The csv file includes the following columns. *
 Average_Baseline_Pa: the average baseline pressure difference between the
 Ductblaster fan (Pa) - Pressurization_C, Pressurization_n: the flow
 constant (c, n) estimated from the pressurization test *
 Pressurization_Q50: Air leakage presented in air change per hour at 50 pa
 difference when pressurizing the house envelope (CFM) -
 Depressurization_C, Depressurization_n: the flow constant (c, n) estimated
 from the depressurization test * Depressurization_Q50: Air tightness
 presented in air change per hour at 50 pa difference when depressurizing
 the house envelope (CFM) - Supply_DuctLeakage_CFM, Return_DuctLeakage_CFM:
 initial estimated supply and return duct leakage (CFM) *
 Supply_DuctPressure: supply duct pressure during the DeltaQ test (Pa) -
 Return_DuctPressure: return duct pressure during the DeltaQ test (Pa) *
 Pressurization_ACH50: Air tightness presented in air change per hour at 50
 pa difference when pressurizing the house envelope  -
 Depressurization_ACH50: Air tightness presented in air change per hour at
 50 pa difference when depressurizing the house envelope  * ACH50: Averaged
 envelope air tightness presented in air change per hour at 50 pa
 difference by considering both pressurization and depressurization -
 Total_DuctLeakage: total duct leakage by summing up both supply and return
 duct leakage (CFM) * Review note: researcher review note for each DeltaQ
 test ### Home_characteristics This folder (Home_Characteristics.zip)
 contains data about the house, including basic characteristics, air
 leakage test results, and measured airflow rates of mechanical ventilation
 equipment. There is one EXCEL file containing TWO spreadsheets: The home
 characters spreadsheet includes data for all homes. Each home data were in
 a column with each measured/estimateda parameter as a row. For the
 parameter that is not applicable to the test house, the cell is filled
 with “NA”. For the parameter that was not checked or measured by the field
 team, the cell is filled with “Not checked” or “Not measured” or “NM”. In
 some cases, the field team cannot determine the condition after field
 check, the cell is filled with “Unclear” or “cannot determined”. Parameter
 description spreadsheet explains parameters in the homes characters
 spreadsheet one by one with the same order as the home characters
 spreadsheet (Column B). And the input abbreviations and general notes
 (Column C). If a cell in Column C was left blank, it means that there is
 nothing special to note for data input for the parameter in the row. ###
 IAQ_Activity_Monitoring This folder (IAQ_Activity_Monitoring.zip) contains
 time-resolved indoor and outdoor air quality data, including PM2.5 as
 measured by MetOne photometry (PM), Radon (Rn), indoor PM (PM1, PM25,
 PM10) concentrations measured by an IQair Air Visual Pro (AVP) low-cost
 sensor, carbon dioxide (CO2), formaldehyde (FRM), temperature (T), and
 relative humidity (RH) in different rooms. Data also included T and RH
 measured at the supply air register, attic and basement (AS, ATT, BS). 
 This folder also contains time series data of cooktop burners and oven
 monitored using iButton temperature sensors (IBU), other cooking devices
 monitored using AC power logger (PTR), whole house mechanical ventilation
 system, kitchen range hood and bathroom fan on/off monitored using either
 an anemometer (ANM) or a motor sensor (MTR), and open/close status of
 doors and windows monitored with state sensors (STA). There is one csv
 file of 1-minute time-series data for each measured week; two-week homes
 are marked as -ON and -OFF. A specific read me file
 (IAQ_Activity_Monitoring_ReadMe) was included in the folder for data
 header definitions and data issues. Most instruments had internal logging
 and special software to download data from the field instruments and
 convert the data files to csv format. One-minute resolution time-series
 data files were created for each house using a python script that pulled
 data from multiple csv files, aligned data by time, executed unit
 conversions, and interpolate data that were measured at different time
 resolutions. Visual review was conducted on the compiled files to check
 for translation or writing errors, indications of instrument malfunction,
 mislabeled units or unit conversion errors, mislabeled location, and time
 stamp errors. Missing data resulting from either instrument failure or
 invalid readings identified by researchers were filled with “NA” in each
 csv file. ### IAQ_Sample This folder (IAQ_Sample.zip) contains the results
 of time-integrated air quality samples, including passive measurements of
 formaldehyde, nitrogen dioxide and nitrogen oxides, and PM2.5 gravimetric
 filter measurements. There are three csv files containing each type of
 measurement. #### Ogawa samplers  The passive Ogawa samplers were
 collected from test homes with gas cooking appliances. The csv file
 contains the exposure information, laboratory extract results from Ogawa
 samplers and the final calculated NO~2~, NO and NO~x~ concentration in ppb
 and µg/m^3^. The spreadsheet contains the following columns. **Sampled
 home ID and Exposure information:** * Week: Measured week for each home,
 1– for one week homes, week1 and week2 for two-week homes and on/off
 indicate the WHMV system status during that week - Deployment Location:
 The samplers deployment location in each test homes. IN1–central location
 (living room); IN1D–Duplicates in the central location; OUT–outdoors;
 BLANK–field blank  * Start Time & Date and Stop Time & Date: the
 start and end times of the sampler deployment, recorded by the field team
 - Elapsed Time (days) and Elapsed Time (min): the elapsed time calculated
 from start and end times in days and minutes **Environmental Data during
 exposure:** * Avg. RH% and Avg. Temp C: average relative humidity and
 indoor temperature during the exposure time in % and Celsius. - PT: Water
 vapor pressure at exposure, calculated based on average indoor temperature
 (mm Hg) * P: Water vapor coefficient calculated based on PT - AlphaNO~2~
 and AlphaNO: NO~2~ and NO adjust constants calculated based on
 Temperature, RH and PT. **IC Data from lab extraction and analysis:** *
 NO~2~ pad-Nitrite Conc: Raw NO~2~ pad concentration from IC extraction
 (ug/mL) - NO~x~ pad-Nitrite Conc: Raw NO~x~ pad concentration from IC
 extraction (ug/mL) * NO~2~ pad-Nitrite Conc. Blank Corrected: NO~2~ pad
 concentration from IC extraction corrected by the field blank (ug/mL) -
 NO~x~ pad-Nitrite Conc. Blank Corrected: NOx pad concentration from IC
 extraction corrected by the field blank (ug/mL) **Final calculated
 NO2/NO/NOx concentration:** * NO2/NO/NOx Blank Corrected: NO~2~/NO/NO~x~
 mass loaded on the pad, calculated from previous two columns (ng) -
 NO~2~/NO/NO~x~: measured air NO~2~/NO/NO~x~ concentration in ppb of each
 sample (ppb) Notes: Notes from field team and researchers during the
 deployment and analysis. The cell is left blank if everything looks
 normal. #### UMEx samplers  The UMEx passive samplers were collected from
 all test homes. The CSV file contains the exposure information and extract
 results for UMEx samplers. Samples were exposed for the full duration of
 sampling at test houses indoors and outdoors with field blanks deployed in
 a few homes. The exposure duration and extracts analysis results were
 listed. The final formaldehyde concentrations were calculated, as shown in
 the unit of parts per billion. The spreadsheet contains the following
 columns. **Sampled home ID and Exposure information:** * Week: Measured
 week for each home, 1– for one week homes, week1 and week2 for two-week
 homes and on/off indicate the WHMV system status during that week -
 Deployment Location: The samplers deployment location in each test homes.
 IN1–central location (living room); IN1D–Duplicates in the central
 location; OUT–outdoors; BLANK–field blank  * Start Time & Date and
 Stop Time & Date: the start and end times of the sampler deployment,
 recorded by the field team - Elapsed Time (days) and Elapsed Time (min):
 the elapsed time calculated from start and end times in days and minutes *
 Volume: total volume of air passing through the sampler during the
 exposure time (L) - Extraction Date: the date that the sample was analyzed
 in the laboratory **Lab analysis and results:** * Formaldehyde (ng): Total
 Formaldehyde mass loaded on the sampler during exposure time (ng) - Blank
 (ng): Formaldehyde mass loaded on the field blank sample. If no field
 sample was deployed for this home, a study average value of 195 ng was
 used. * Formaldehyde (ug/m^3^): Calculated Formaldehyde air concentration
 in each home in ug/m^3^ - Formaldehyde (ppb): Calculated Formaldehyde air
 concentration in each home in ppb Notes: Notes from field team and
 researchers during the deployment and analysis. The cell is left blank if
 everything looks normal. #### PEM samples The PEM sampler collected
 gravimetric PM2.5 mass on a PTFE filter through a pump that continuously
 ran indoors (IN) and outdoors (OUT) at each test home. The gravimetric
 PM2.5 concentration was calculated using total volume of the air passing
 through the filter during the elapsed time and the mass load, as shown in
 the unit of microgram per cubic meter. Invalid measurements due to
 instrumentation or analysis were filled with “NA”. The spreadsheet
 contains the following columns. **Sampled home ID and Exposure
 information:** * Week: Measured week for each home, 1– for one week homes,
 week1 and week2 for two-week homes and on/off indicate the WHMV system
 status during that week. cross-cal# means the sample was used in a lab
 space for instrument cross calibration. - Deployment Location: The
 samplers deployment location in each test homes. IN1–central location
 (living room); IN1D–Duplicates in the central location; OUT–outdoors;
 BLANK–field blank  * Start Time & Date and Stop Time & Date: the
 start and end times of the sampler deployment, recorded by the field team
 - Elapsed Time (days) and Elapsed Time (min): the elapsed time calculated
 from start and end times in days and minutes * Avg, Flow (LPM): The
 average flow rate of the pump extracting air for the PEM sampler (LPM)
 measured at Pre-deployment and post-deployment. - Volume: total volume of
 air passing through the sampler during the exposure time (L) **Lab
 analysis and results:** * Mass Loading (ug): The mass load of PM2.5 on the
 filter, which was calculated based on the pre- and post weight of the PTFE
 filters.  - Conc (ug/m^3^) No Blank used: The calculated PM2.5
 concentration for each sample, with no field blank subtracted from the
 value (ug/m^3^). * Notes: Notes from field team and researchers during the
 deployment and analysis. The cell is left blank if everything looks
 normal. ### Occupant_Activity This folder (Occupant_Activity.zip) contains
 tabulated information provided by study participants from their daily
 activity logs. The PDF file is an example of the format of activity log
 used in the field study. A researcher manually transcribed the handwritten
 logs into a CSV file for each measured week in each home. There are a
 total of 32 CSV files named by home_ID + total days of record in the
 folder.  The activity logs were in hourly blocks, the blocks were filled
 with “X” or number of hours that an activity happened in this hour. If
 nothing happened in this hour, the block was left blank, without any “NA”
 filled. If other activities that were not listed in the logs happened,
 occupants were asked to fill in “other_event” rows and indicate in the
 “note”. The customized codes are summarized in
 ICRT_activity_logs_code.csv. ### Occupant_Survey This folder
 (Occupant_Survey.zip) contains survey results about the occupants, their
 general activities related to ventilation and IAQ satisfaction, completed
 by study participants. There is one csv file containing data transcribed
 by a researcher. In the csv file, each row represents the response from a
 home. Each column represents a survey question. The pdf file contains
 questions of the occupant surveys.  In some homes, the occupants did not
 complete the survey, the survey questions that were left blank were filled
 with “-99”. For the survey questions that are not available for the test
 house and household, the results are filled with “NA”. Human
 identification information have been masked. ### WHMV_Config This section
 (WHMV_Config.zip) provides detailed information about the Whole-House
 Mechanical Ventilation (WHMV) systems in each study home. The data were
 extracted from the Home_Characteristics spreadsheet, reviewed by
 researchers and field teams, and supplemented with additional information
 as needed. If discrepancies exist between the HomeCharacteristics table
 and the spreadsheets in this section, the information presented here
 should be considered authoritative. The folder has one excel file and one
 txt readme file contains some analysis notes. The accompanying Excel file
 contains two worksheets: Week 1 (AS-IS WHMV): documents the WHMV system
 condition observed when researchers first arrived at each home. Week 2
 (≥100% 62.2–2010): documents the WHMV condition in homes that underwent a
 second week of monitoring, during which multiple bathroom fans were
 operated continuously by the researcher to meet the WHMV requirements of
 ASHRAE 62.2–2010 and 62.2–2013. Columns explanation: * Ventilation Type
 (Field config): the WHMV type initially configured by the field team. -
 Ventilation Type (Revised): the WHMV type revised, homes with bathroom
 fans that had a rated sound level &lt;1 sones were considered as potential
 WHMV equipment to meet 62.2. Those homes were re-listed as EXH. * Control
 Type: WHMV control type. - Label At Controller: Label condition and
 whether it met 62.2 labeling requirements. * WHMV operating on arrival:
 Whether WHMV was operating at the field team’s first arrival. - 62.2-2010
 min airflow (CFM): 62.2-2010 continuous ventilation minimum required
 airflow for each house. * WHMV airflow (cfm) as found: the measured WHMV
 airflow at the field team’s first arrival. - WHMV runtime (min/hr) as
 found: the WHMV runtime at the field team’s first arrival. * Calculated
 WHMV airflow (cfm): effective WHMV airflow calculated from airflow and
 runtime - Ratio: AS-FOUND ventilation rate 62.2-2010: ratio of WHMV
 airflow to 62.2-2010 requirement, shown in percentage. * WHMV
 indoor/outdoor exhaust/intake location: WHMV exhaust and intake locations
 - 2-week study: whether the house was undergone for a 2nd week study ##
 Human subjects data This study was reviewed and approved by the Central
 Institutional Review Board (IRB) of the U.S. Department of Energy. All
 participants provided written informed consent, which included permission
 to publish their de-identified data in the public domain for research and
 educational use. To protect participant privacy, all personally
 identifiable information (PII)—including names, addresses, precise
 geolocation, and contact information—has been removed or anonymized. Each
 home was assigned a randomly generated study ID that does not correspond
 to any internal or field-collected identifier. Time stamps were
 generalized as needed to prevent potential re-identification, and no
 free-text responses or media content are included. The dataset has been
 reviewed to ensure that the risk of re-identification is minimal, in
 compliance with established data protection standards.​​