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It is costly to sample all air pollutants of a general community for continuous indoor air quality (IAQ) assessments. To optimize the resources for IAQ baseline monitoring for general facilities management, this study aims to investigate the feasibility of using a simple IAQ index as a screening parameter of a screening test to identify an asymptomatic air‐conditioned office with probable unsatisfactory IAQ.

The IAQ index is determined from the fractional dose of some representative common indoor air pollutants of unsatisfactory IAQ, either by taking equal importance of the pollutants as a weighting factor or weighted by the regional failure rates with respect to the corresponding air pollutants. Specifically, a database of regional IAQ assessment results of 422 air‐conditioned offices was employed to justify the selected screening levels for the IAQ index.

The proposed IAQ index of a screening assessment was used for verifying, respectively, 58 and seven air‐conditioned offices of Hong Kong with satisfactory and unsatisfactory IAQ. The results showed that 57 satisfactory offices and two unsatisfactory offices were correctly identified by the unweighted and weighted IAQ indices respectively. Evaluation of the proposed index in further IAQ improvements of some offices showed that it would be a practical tool for preliminary IAQ screening assessment.

The screening test itself could not identify all the IAQ problems but could identify the office groups with higher risk of unsatisfactory IAQ with reduced effort.

The study shows the usefulness of the proposed IAQ index to identify the unrecognized IAQ problems for air‐conditioned office environments. It could be adopted as a routine screening measure in facility management of which a wide‐ranging set of IAQ measurement is undesired.

This study presents a useful reference for policymakers, building owners and professionals for indoor environmental assessments.

To examine the role of predicted mean vote (PMV) in air‐conditioned environments by conducting a thermal comfort study.

A formal statistical approach was adopted for the credibility of the study. Thermal measurements and questionnaire filling were carried out in commercial offices to collect the required data. Statistical analysis on the collected data and logical reasoning were then employed to derive the conclusions.

Provide an evidence to support PMV to be an appropriate thermal comfort index in air‐conditioned environments. Guarantee high productivity of occupants by using PMV in air‐conditioning control.

Future research work should be carried out to investigate any significant relationship between improvement in PMV and the profits gained by occupants inside an air‐conditioned space. With such relationship, it is possible to develop an intelligent air‐conditioning control to yield the most cost‐effective thermal environments for commercial offices.

Air‐conditioning engineers are highly recommended to employ PMV to assess the thermal comfort environment in air‐conditioned offices.

This paper highlights the importance aspect on choosing a thermal comfort index for comfort assessment in air‐conditioned offices. The index itself should not consider adaptive actions. Otherwise, the productivity of occupants would be severely deteriorated. It is well known that PMV is the thermal comfort index that can fulfill this requirement.

Looks at complexity in office buildings and its consequences, desirable and undesirable. Draws on evidence from studies of comfort, control, productivity, health, energy efficiency and human satisfaction carried out in offices in the United Kingdom since 1985. From this work, it is known that many office buildings do not function as well as their designers originally intended. They are frequently uncomfortable for their occupants, especially in summer, and too often make people chronically ill. This results in lower human productivity – a substantial hidden cost to many organizations. Their energy consumption is often excessive and, consequently, so are their emissions of carbon dioxide, which is one of the causes of global warming.

There is growing concern in the more affluent, developed countries about the possible relationship between the environment created in energy‐efficient, high‐tech, air‐conditioned buildings, and the health problems of occupants. Over the past decade there has been a considerable increase in interest shown in the indoor air quality of offices, due in the main to improvements in measuring indoor air contaminants, a greater understanding of the health effects and the fact that 80 to 90 per cent of people now spend their time indoors. There is also a greater public awareness of the need for an adequate working environment. It is significant that the increased involvement of unions in white collar areas of work has generated considerable debate on the subject of hazards in the office environment which coincides with the national and international concern now materialising.

The purpose of this paper is to propose a screening test for indoor air quality (IAQ) assessment by auditing only a few “dominant” contributors for preliminary measurements in air‐conditioned offices.

In Hong Kong, up to ten common indoor air pollutants have to be audited in determining the IAQ acceptance for typical air‐conditioned offices. Indeed, parameters could not be uniformly contributed to the assessed “IAQ satisfaction”. The study reviews the past ten‐year assessment experiences in Hong Kong and investigates the “dominant” contributors of unsatisfactory IAQ for screening tests.

When compared with the “full” assessment of all ten listed parameters, a screening test with assessment parameters reduced by half would correctly identify 96 per cent unsatisfactory and 95 per cent satisfactory cases.

The screening test was developed with the reported patterns of the ten common air pollutants from on‐site measurements and survey studies in typical air‐conditioned offices in Hong Kong. Therefore, the test application may require adaptation for use in other countries.

The study shows the usefulness of a regional database in developing a screening strategy for IAQ and so it would be a useful reference for policymakers in evaluating a cost‐justified IAQ assessment protocol.

The paper proposes a simple screening test which can identify the probable unsatisfactory IAQ in offices by assessing only a few “dominant” contributors, with selection of representative assessment parameters based on experiences.

This study seeks to investigate the usefulness of occupant acceptance as a preliminary screen measure for offices' indoor air quality (IAQ). An effective alert indication of IAQ problems of a concerned indoor environment would help to promote good IAQ.

The study evaluates the hypothesis that the occupant dissatisfaction with the overall indoor environment provides an indication of IAQ problems. Hence, occupant dissatisfaction would be used as a screening parameter to identify problematic IAQ regarding some IAQ criteria in subsequent IAQ assessments. The hypothesis was tested with a database of regional cross‐sectional measurement in 490 offices within Hong Kong.

The occupants' dissatisfaction with the indoor environmental quality (IEQ) was correlated with the IAQ assessment results of nine IAQ assessment parameters regarding some IAQ criteria for air‐conditioned offices. At certain screening levels of predicted IEQ dissatisfaction, the performance of the proposed screening tool, indicating unsatisfactory office IAQ, was evaluated in terms of the test sensitivity, specificity, predictive values and Yule's Q statistics. The results showed that occupants' response to the indoor environment produced indications of unsatisfactory IAQ regarding the requirement of an “Excellent” office.

The subjective feelings of occupants are capable of identifying marked indoor environmental problems, but cannot identify the “marginal” IAQ problem cases.

The study shows the usefulness of using occupant acceptance to identify the unrecognized IAQ problems for air‐conditioned office environment. Using the identification model developed in the study, all the suspected cases were associated with a high chance of IAQ dissatisfaction and subsequent IAQ assessments were thus recommended.

The paper proposes a new identification method to identify the unrecognized IAQ problems which may indicate unsatisfactory IAQ. Also, the occupants' responses on the indoor environment are quantified.

Sick building syndrome is recognized by the World Health Organization. It is characterized by employees suffering from a range of symptoms which are associated with being in a particular building and are relieved by leaving it or staying away. Discusses the results of a survey which examined the extent and possible causes of sick building syndrome in libraries. Questionnaires were sent to all academic libraries in Great Britain together with a sample of public libraries. The evidence suggests that sick building syndrome exists in libraries and that air‐conditioned libraries are more likely to be affected than those which are naturally ventilated.

Considers the condition of sick building syndrome and the factors that may cause it. Discusses the definition of SBS, the likely causes, physical factors, indoor pollution, personal factors, organizational factors, when SBS can be definitely diagnosed, and future plans. Surmises that significant reductions in SBS can be achieved at little or no cost in many cases, to the benefit of productivity and reduced costs.

Maintaining good indoor air quality (IAQ) in the built environment is essential to assure health, safety and productivity of occupants. The purpose of this paper is to report on the preliminary IAQ assessment of selected air-conditioned laboratories and naturally ventilated workshops in a tropical education institution.

The concentration levels of five major indoor air pollutants (IAPs) – carbon dioxide, carbon monoxide, respirable particulates, formaldehyde (HCHO) and total volatile organic compounds (TVOC) in each sampling area were measured using calibrated air sampling sensors and the tracer-gas analysis was used to determine the ventilation effectiveness. A questionnaire survey was carried out concurrently to study the prevalence of sick building syndrome (SBS) among users of laboratories and workshops and the data collected were statistically analysed using χ² test.

The air pollutant levels were found to be below the threshold limit values set in the local code of practice on IAQ, except for two of the air-conditioned laboratories. This is possibly due to insufficient ventilation, smaller floor area per occupant ratio, long-term exposure to chemical substances, and improper disposal of the used chemical substances. The total particulate levels were higher in naturally ventilated workshops because such spaces were assigned for mechanical works which involved grinding, welding and fabrication. Besides, it was identified that most of the air contaminant levels were not normally distributed (p<0.05) within the sampling areas and SBS like dry eyes, watery eyes, tiredness and dry throat were reported in both laboratories and workshops. The outcomes of this work suggest that an increase of ventilation rate was necessary to reduce the concentration of the IAPs in air-conditioned laboratories and improved housekeeping would help mitigate the prevalence of SBS symptoms.

This research was carried out in selected laboratories and workshops in a Malaysian educational institution and only five major IAPs stipulated in the Department of Occupational Safety and Health (DOSH) code of practice were measured.

The results of this study will enable facility engineers and managers to understand the IAPs concentration levels and potential SBS problems in academic laboratories and workshops. The recommended strategies can be considered to improve IAQ conditions in such spaces.

Most of the previously conducted IAQ studies focused only on commonly occupied building spaces such as offices, classrooms and houses. Information of the quality of air and SBS conditions in experimental facilities in developing nations that is available is currently very limited. This case study provides detailed information on IAQ in laboratories and workshops in Malaysia with focuses on the concentration levels of particular harmful gases, the prevalence of SBS among users of these facilities and the appropriate mitigation strategies. The results presented are of value to both academic and industry communities.

As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation.

Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices.

Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient.

This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions.

This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment.

There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey.