João Dias Carrilho

Measurement of Infiltration Rates from the Daily Cycle of Ambient CO2

Abstract A new approach for measuring air infiltration rates in buildings is proposed. The method belongs to the class of tracer gas techniques but, unlike conventional CO2 based methods that assume the outdoor ambient CO2 concentration is constant, the proposed method recognizes that photosynthesis and respiration cycle of plants and processes associated with fuel combustion produce daily, quasi-periodic, variations in the ambient CO2 concentrations. These daily variations, which are within the detection range of existing monitoring equipment, are utilized for estimating ventilation rates without the need of a source of CO2 in the building. The new method has the advantages that no tracer gas injection is needed, and time resolved results are easily obtained.

Real time web publishing of environmental noise monitoring data

This paper summarizes the steps that were followed in the creation of a dynamic webpage for publishing, in real time, the data from the Environmental Noise Monitoring station installed at the Association for the Development of Industrial Aerodynamics (ADAI), at the University of Coimbra. The webpage has been used as part of a remote laboratory activity in a distance learning course about indoor environment comfort in buildings, organized by the University of Coimbra.