Analysing longitudinal indoor air quality data: robust principal component analysis of the “Schools’ Air quality Monitoring for Health and Education” timeseries data
File(s)
Published version
Author(s)
Handy, Alice EE
Wood, Samuel GA
Burridge, Henry
Type
Journal Article
Abstract
A robust principal component analysis examining two-years of monitored data from within 143 UK schools as part of the “Schools’ Air quality Monitoring for Health and Education” dataset sheds new light on the temporal and geographical trends that influence the schools’ air quality. Minutely concentration measurements of two indoor air quality markers, particulate matter and carbon dioxide, were analysed. Significant inter-school variations were evident in both species but the primary source of variations within the particulate matter concentrations were temporal trends. Analysis links these temporal trends to variations in outdoor particulate matter concentrations — highlighting the importance of outdoor air quality for the air quality in UK schools. Moreover, clear geographical signatures are identified within the particulate matter concentrations in schools, broadly increasing both South–North and East–West; with more subtle but intelligible trends overlaid within each. Analysis of the carbon dioxide data identifies variations on a range of time scales from seasonal trends, associated with the changing levels of ventilation as UK schools open their windows less in cooler wintertime conditions, down to inter-day variations as carbon dioxide levels increase during the school morning. This study provides the first evidence as to the insights that can be gained when large-scale longitudinal monitoring of indoor spaces, in this case schools, is carried out. The insights that were determined from analysis of two-years of data from the SAMHE schools could not have been realised by analysis of smaller datasets.
Date Issued
2026-01-30
Date Acceptance
2025-12-15
Citation
Indoor Environments, 2026, (1)
ISSN
2950-3620
Publisher
Elsevier BV
Journal / Book Title
Indoor Environments
Issue
1
Copyright Statement
© 2025 The Authors. Published by Elsevier Inc. on behalf of International Society of Indoor Air Quality and Climate. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
License URL
Identifier
10.1016/j.indenv.2025.100146
Publication Status
Published
Article Number
100146
Date Publish Online
2025-12-16