Introduction
Since the total number of permanent air quality
monitoringstations in a city is limited due to practical
constraints (e.g. cost and bulk of equipment, power
supply, etc.), alternative measurement and modellingtechniques are needed in order to assess urban air
quality with respect to population exposure and
compliance with regulations. It is particularly important
to ensure that the use of available monitoringequipment
is optimised and that the obtained data are properly
interpreted