Evaluation on screening strategies for indoor air quality assessments in air-conditioned offices

Unsatisfactory indoor air quality (IAQ) in air-conditioned offices would make the occupants uncomfortable and lead to productivity loss. Strategic IAQ monitoring and assessment conducted with optimised resources for representative pollutants and air sampling are developed. This study proposes a simple screening process; with a readily developed IAQ express assessment protocol (EAP), to improve the accuracy in screening the office environment of unsatisfactory IAQ. This screening process is conducted with an `IAQ index', correlated with an event of unsatisfactory IAQ regarding its `failure' due to other six unmeasured air pollutant levels in the EAP; where the IAQ index is defined as the average fractional dose to certain exposure limits from the assessed top dominant contributors. The screening strategies were examined against the existing IAQ assessment results.

Practical applications: Testing on the screening strategies for EAP in 422 air-conditioned offices in Hong Kong showed that, with a defined screening level of probability of unsatisfactory IAQ, the proposed screening process would improve the overall performance of EAP. It would be a useful source of reference in setting up any practical public IAQ surveillance programmes for policymakers, building owners and professionals to quantify the IAQ problems in offices and make decisions on resources and manpower management for efficient mitigation actions.