DOI: 10.7941/d1t050
title: Indoor air quality in new and renovated low‐income apartments with mechanical ventilation and natural gas cooking in California

description: This study presents pollutant concentrations and performance data for
 code-required mechanical ventilation equipment in 23 low-income apartments
 at 4 properties constructed or renovated 2013-2017. All apartments had
 natural gas cooking burners. Occupants pledged to not use windows for
 ventilation during the study but several did. Measured airflows of range
 hoods and bathroom exhaust fans were lower than product specifications.
 Only eight apartments operationally met all ventilation code requirements.
 Pollutants measured over one week in each apartment included time-resolved
 fine particulate matter (PM2.5), nitrogen dioxide (NO2), formaldehyde and
 carbon dioxide (CO2) and time-integrated formaldehyde, NO2 and nitrogen
 oxides (NOX). Compared to a recent study of California houses
 with code-compliant ventilation, apartments were smaller, had fewer
 occupants, higher densities, and higher mechanical ventilation rates. Mean
 PM2.5, formaldehyde, NO2, and CO2 were 7.7 µg/m3, 14.1 ppb, 18.8 ppb, and
 741 ppm in apartments; these are 4% lower, 25% lower, 165% higher, and 18%
 higher compared to houses with similar cooking frequency. Four apartments
 had weekly PM2.5 above the California annual outdoor standard of 12 µg/m3
 and also discrete days above the World Health Organization 24-h guideline
 of 25 µg/m3. Two apartments had weekly NO2 above the California annual
 outdoor standard of 30 ppb.
description: This study evaluated IAQ in 23 low-income apartments at 4
 properties with natural gas cooking burners and mechanical ventilation
 equipment having specifications that met state building code requirements.
 The inclusion criteria were for apartment units to have (1) mechanical
 ventilation (MV) equipment that met the requirements of California’s Title
 24 residential building code and (2) a natural gas cooking appliance.
 Required MV equipment were an exhaust fan in each bathroom, a kitchen
 exhaust fan or range hood, and equipment providing regular ventilation to
 the dwelling unit – each having specifications that met the code-minimum
 airflow requirements. Each property was visited in
 advance of the week of monitoring to confirm the presence of compliant MV
 equipment; this was done by inspecting 2-4 unoccupied units per site.
 Recruitment commenced following this visit. During the first visit, teams
 provided the participant with a paper version of the survey to obtain
 information about satisfaction with air quality and thermal conditions in
 the home and routine activities that impact ventilation and IAQ.
 Characteristics of mechanical ventilation equipment, cooking appliances,
 and thermal conditioning systems were documented and unit airtightness and
 ventilation equipment airflows were measured. Temperature, humidity,
 carbon dioxide and air pollutant concentrations were measured inside each
 apartment and air pollutant concentrations were measured outdoors on site.
 Sensors were installed to monitor use of gas cooking burners, ventilation
 equipment, and natural ventilation. Participants were asked to record
 occupancy and activities during each day of monitoring. Surveys and
 activity logs were collected and equipment was removed after one week of
 monitoring in each apartment. The study was led by
 Lawrence Berkeley National Laboratory (LBNL). Association for Energy
 Affordability recruited study buildings and completed a large portion of
 the field work. All study protocols involving interactions and collection
 of data from private individuals and monitoring in occupied homes were
 reviewed and approved by the LBNL Human Subjects Committee. Research
 Funding and technical contributions of collaborators are noted below in
 the acknowledgements.
description: What is contained in this dataset? The
 dataset contains the most relevant information collected about the
 apartments and 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 apartments
 Organization of Dataset
 Home_Equipment_Data This folder 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 the data for all homes. The home
 characteristics form used by the field team is also included in the folder
 to explain the data parameters used in the EXCEL file.
 IAQ_Activity_Monitoring This folder contains
 time-resolved indoor and outdoor air quality data, including raw and
 adjusted PM2.5 as measured by DustTrak and PDR photometry (PM), ultrafine
 particles number concentration (UFP), PM concentrations measured by
 low-cost sensor (PM1, PM25, PM10), carbon dioxide (CO2), nitrogen dioxide
 (NO2), formaldehyde (FRM), total volatile organic compound (tVOC),
 temperature (T), and relative humidity (RH). Data also included T and RH
 measured at the supply air register (AS). Data also include hourly outdoor
 PM2.5 and NO2 concentration form the closest regulatory air monitoring
 stations (AQS). This folder also contains time series
 data of cooktop burners and oven monitored using iButton temperature
 sensors, other cooking devices monitored using AC power logger, kitchen
 range hood and bathroom fan on/off monitored using either an anemometer or
 a motor sensor, and open/close status of doors and windows monitored with
 state sensors. There is one csv file of 1-minute time-series data for each
 home, total 23 csv files. See
 KV_IAQ_Activity_Monitoring_ReadMe 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. More
 detailed information about data issues identified are explained in the
 ReadMe file. IAQ_Sample This
 folder 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 is one
 EXCEL file containing all data. Detailed information about chemical
 analysis of air samples are provided elsewhere in the journal
 paper. Occupant_Activity This
 folder contains tabulated information provided by study participants from
 their daily activity logs. There is one EXCEL file containing data
 transcribed by a researcher, which was independently spot checked by
 another researcher to confirm accuracy. The PDF file shows the format of
 the daily activity log used.
 Occupant_Survey This folder contains survey
 results about the occupants, their general activities related to
 ventilation and IAQ satisfaction, completed by study participants. There
 is one EXCEL file containing data transcribed by a researcher. Two homes
 did not complete surveys, as indicated by "No survey" in the
 response. The MS Word file contains questions of the occupant
 surveys.