ageing

The three common tracer injection strategies all proved reliable in a test chamber under complete mixing conditions. For field studies of air flow patterns in large rooms the step-up method or the pulse method is recommended to escape the initial complete mixing condition of the decay method.

This report describes tracer gas measurements of the local mean age of air at different locations within an office room. These results are used to assess the distribution of fresh air atdifferent depths, and to give guidance on the depth over which single-sided ventilation is effective.