Development of a decision support system for the design of good indoor air quality in office buildings : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Product Development at Massey University, Turitea, New Zealand

Abstract

Office buildings are complex entities. Design decisions can affect the quality of the indoor air (IAQ) throughout the life of the building. Poor IAQ affects approximately 30% of all office buildings and is ranked within the five greatest risks to human health in developed countries. Despite a vast and growing body of scientific literature on IAQ, there is a large gap between the current knowledge and the application of this knowledge in building practices. The USA Environmental Protection Agency identified a high priority need for design and educational tools to assist building designers who are not experts in IAQ issues to create healthy buildings. In this study a Decision Support System (DSS) for the design of good IAQ in office buildings was developed. The DSS leads building designers through a structured question database on building attributes that affect IAQ. Full justification for each design decision is given in order to prompt designers to select building features that lead to low indoor concentrations of volatile organic compounds, gaseous pollutants, microbiological contaminants and respirable particulates. The DSS was developed for new office buildings in New Zealand conditions, with either natural or mechanical ventilation. An exisiting methodology for the development of DSS was used. The problem was approached from the perspective of the building users under the broad headings of site and external factors, building envelope, building infrastructure, interiors, and heating ventilating and air-conditioning. Each of these topics was subdivided into finer layers of detail until conclusions on the potential impact of each building element on the IAQ could be inferred. The hierarchy for decision-making placed highest priority on the elimination or reduction of pollutants at source. Opportunities for pollutants to enter from outside or spread within the building were also controlled. If either of these strategies were not found acceptable, then mitigation techniques were recommended. A panel of independent national and international experts validated the DSS for correctness and completeness. The reviewers reported that the system was very comprehensive, drew correct conclusions and would assist building designers without IAQ expertise, to design office buildings with good IAQ. The DSS was also considered to have a significant educational component for users.