The aim of this work was to investigate changes in particle number concentration (PNC) within naturally ventilated primary school classrooms arising from local sources either within or adjacent to the classrooms. We quantify the rate at which ultrafine particles were emitted either from printing, grilling, heating or cleaning activities and the rate at which the particles were removed by both deposition and air exchange processes. At each of 25 schools in Brisbane, Australia, two weeks of measurements of PNC and CO2 were taken both outdoors and in the two classrooms. Bayesian regression modelling was employed in order to estimate the relevant rates and analyse the relationship between air exchange rate (AER), particle infiltration and the deposition rates of particle generated from indoor activities in the classrooms. During schooling hours, grilling events at the school tuckshop as well as heating and printing in the classrooms led to indoor PNCs being elevated by a factor of more than four, with emission rates of (2.51 0.25)  1011 p min1 , (8.99 6.70)  1011 p min1 and (5.17 2.00)  1011 p min1 , respectively. During non-school hours, cleaning events elevated indoor PNC by a factor of above five, with an average emission rate of (2.09 6.30)  1011 p min1 . Particles were removed by both air exchange and deposition; chiefly by ventilation when AER > 0.7 h1 and by deposition when AER < 0.7 h1 .

Item Type:	Refereed Article
Keywords:	ultrafine particles, deposition rates, schools
Research Division:	Earth Sciences
Research Group:	Atmospheric Sciences
Research Field:	Atmospheric Aerosols
Objective Division:	Environment
Objective Group:	Air Quality
Objective Field:	Urban and Industrial Air Quality
Author:	Salimi, F (Dr Farhad Salimi)
ID Code:	105249
Year Published:	2014
Web of Science® Times Cited:	18
Deposited By:	Menzies Institute for Medical Research
Deposited On:	2015-12-16
Last Modified:	2016-08-08
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