Fungi — an indoor air quality assessment parameter for air-conditioned offices

Abstract

Representative assessment parameters are proposed for indoor air quality (IAQ) audit in various strategies and guidelines.1 In Hong Kong, assessment of indoor airborne fungi is not incorporated in many IAQ audits of air-conditioned offices, although the exposure to airborne fungi could cause a variety of adverse health effects. An IAQ assessment for a local office will audit 12 parameters, including air temperature, relative humidity, air velocity, carbon dioxide, carbon monoxide, respirable suspended particulates, nitrogen dioxide, ozone, formaldehyde, total volatile organic compounds, radon, and airborne bacteria. This paper reviews recent studies of the indoor airborne fungi levels and IAQ assessments in some air-conditioned offices of Hong Kong and evaluates the contribution of the airborne fungi to an unsatisfactory IAQ in the environment. The unsatisfactory rates regarding the assessment parameters were evaluated using the Monte Carlo simulations with measured data in Hong Kong Offices. In particular, the impact of selecting representative IAQ assessment parameters was examined against an express assessment protocol (EAP), which assessed some dominant contributors of unsatisfactory IAQ.2 The results reported that the three top ranked contributors for unsatisfactory IAQ were total volatile organic compounds (TVOC), indoor airborne fungi count (AFC) and airborne bacteria count (ABC) for air-conditioned offices of Hong Kong.

Practical applications: This study has shown that the assessments of airborne fungi levels in office environment is an important issue and further investigations for the airborne fungi in the IAQ audits were thus recommended. The results of this study could be a useful source of reference for policymakers in evaluation of an effective IAQ assessment protocol with some representative IAQ assessment parameters.

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