This paper gives a presentation of the current research being carried out at NSIB with the aim of exploring the effectiveness of ventilation systems in controlling contaminant levels. The key concepts used for quantifying the performance are; the age distribution of both air and contaminants. The air exchange effective- ness and the average ventilation efficiency are derived from the age distributions. Measurements of the performance of different ventilation s systems are given, expressed in terms of the key concepts above.
The relationship between the observed concentration of air pollutants at points within a building and the characteristics of the ventilation system is examined, and a basic set of analytical expressions showing these relationships is presented. The extension to large and complex systems is considered, and an example of the application of the equations to an actual air quality problem is given.
Effectiveness of ventilation as a major means of controlling indoor air quality was evaluated by correlating concentrations of gaseous (CO and CO2) and particulate (total) pollutants with two ventilation parameters. Pollutants are differently af
The tracer technique can be used in ventilation and contaminant spreading investigations. We have chosen sulphur hexafluoride. We have constructed aspecific instrumentation to perform indoor tests. All components are portable and battery operable. We use generators with remotely controlled flow, real-time chromatographs as analysers, continuous SF6 monitors and field-use calibrators. We have performed numerous tests, in the nuclear industry (Laboratories, reprocessing facilities and PWR), in conventional industries and in hospitals.
A multiple tracer gas method for following air movement in buildings has been developed and demonstrated at the Polytechnic of Central London. This paper describes the method and shows how it is being used to investigate: 1. the whole house inf
Tracer gas techniques, used for routine ventilation checks or trouble shooting are outlined with emphasis on their applicability in a variety of situations.
This paper presents a method for a more accurate calculation of air exchange in the mechanical ventilation of industrial halls with uniformly distributed heat load. The method has been developed on the basis of finding the relation between the
As measurements are essential for performance assessment, models are essential for design. Both empirical and rational models are being developed for predicting the effectiveness of ventilation for acceptable indoor air quality. In this status report, models for contaminant generation rates, and dilution and removal control are introduced through a simple, one-compartment model.
Ventilation studies using small-scale water models have, especially in Norway gained new and important knowledge in industrial ventilation the last 15 years. The outcome has been twofold. First of all it has resulted inimportant experience
Sick building syndrome has up until recently been diagnosed from complaints by the users of the building. Specific causes of complaints symptoms usually have not been identified. Inspection methods have been limited. Frequency of sick buil
Login