Indoor air quality is affected by many factors, including energy provision/use. The main objective of this research was to investigate indoor air pollutant emissions due to energy use in residential buildings, with a specific focus on particulate matter (PM). Three environments were compared: (a) a rural house with an electric cooker; (b) a city-centre flat with a gas cooker; and (c) an urban flat on a main road, also with gas appliances. Concentrations of PM, CO, NO 2 and VOCs were measured in the kitchens and emission rates were calculated for cooking periods. Although there has been a great deal of research examining the effects of gaseous pollutants in the indoor environment, this is one of the first studies to specifically focus on PM. Most particles were small ( 2.5 mm) and thus respirable. The elemental analysis of the PM revealed high metal concentrations (Fe/Na/Zn), whilst their morphologies indicated these were present as salt, skin and particles of biological origin. Gaseous emissions, particularly NO 2 and CO, were more prevalent in homes with gas appliances, since these are a significant source of both pollutants.Nomenclature a ¼ Air exchange rate (h À1 ) C in ¼ Indoor mass concentration of pollutants (mgÁm À3 ) C out ¼ Outdoor mass concentration of pollutants (mgÁm À3 ) EDS ¼ Energy dispersion X-ray systemOxides of nitrogen p ¼ Penetration coefficient across building envelope PM ¼ Particulate matter S e ¼ Emission rate (mgÁh À1 ) SEM ¼ Scanning electron microscopy t ¼ Sampling time (h) V ¼ Volume of the room (m 3 ) VOCs ¼ Volatile organic compounds Át ¼ Cooking time (h) RVOCs ¼ Sum (total) of top 20 volatile organic compounds ß The Author(s), 2012. Reprints and permissions: http://www.sagepub.co.uk/journalsPermissions.nav