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To evaluate the control strategy for a hybrid natural ventilation wind catchers and air‐conditioning system and to assess the contribution of wind catchers to indoor air environments and energy savings if any.

Most of the modeling techniques for assessing wind catchers performance are theoretical. Post‐occupancy evaluation studies of buildings will provide an insight into the operation of these building components and help to inform facilities managers. A case study for POE was presented in this paper.

The monitoring of the summer and winter month operations showed that the indoor air quality parameters were kept within the design target range. The design control strategy failed to record data regarding the operation, opening time and position of wind catchers system. Though the implemented control strategy was working effectively in monitoring the operation of mechanical ventilation systems, i.e. AHU, did not integrate the wind catchers with the mechanical ventilation system.

Owing to short‐falls in the control strategy implemented in this project, it was found difficult to quantify and verify the contribution of the wind catchers to the internal conditions and, hence, energy savings.

Controlling the operation of the wind catchers via the AHU will lead to isolation of the wind catchers in the event of malfunctioning of the AHU. Wind catchers will contribute to the ventilation of space, particularly in the summer months.

This paper demonstrates the value of POE as indispensable tool for FM professionals. It further provides insight into the application of natural ventilation systems in building for healthier indoor environments at lower energy cost. The design of the control strategy for natural ventilation and air‐conditioning should be considered at the design stage involving the FM personnel.

A combined windcatcher and light pipe (SunCatcher) was installed in the seminar room at the University of Reading, UK. Monitoring of indoor environment in real weather conditions was conducted to evaluate the application of windcatchers for natural ventilation. In addition, a subjective occupancy survey was undertaken. External weather conditions and internal indoor air quality indicators were recorded. The “tracer‐gas decay” method using SF₆ was used to establish air change rate for various conditions. The results indicated that the ventilation rate achieved through the windcatcher depends on the difference between internal and external air temperatures, and on wind speed and direction, in agreement with other published work in the area. The indoor air quality parameters were found to be within acceptable levels when the windcatcher was in operation. The measured air change rate was between 1.5ac/h and 6.8ac/h. Occupants’ questionnaires showed 75 per cent satisfaction with the internal conditions and welcomed the installation of the systems in UK buildings.

To reach building owners, architects, designers, builders and manufacturers of materials and building components in order to achieve good indoor air quality (IAQ).

The emission classification of building materials is a part of the Classification of Indoor Climate 2000, which is intended to be used in the design and construction of healthier and more comfortable buildings and their mechanical systems in Finland.

Manufacturers have developed new products with lower emissions by using advanced consistency of materials and improved technology in production and production control. Over the years they have improved the quality of their products so that measured harmful emissions have lowered drastically. Similar development has also been seen in the measured sensory emissions of classified materials and products. In January 2006, there were over 900 classified products.

It is necessary to expand the emission classification of building materials because of the IAQ problems that have arisen related to emissions in the last few years. The methodology is intended for national use, but it is possible to implement the system in other countries.

The emission classification of building materials includes target values for odours and emissions of the materials and recommended maximum surface areas of the materials based on their emissions.

This paper fulfils an identified information/resources need. It is thought‐provoking and offers insights for the future planning and developing of classification systems.

The purpose is to present parameters of a new design code, which is intended to control the indoor air environment for sports buildings in China.

Based on requirements of international sports federations the characteristics of indoor airflow of sports buildings in China, include the parameters of indoor air environment of gymnasiums and natatoriums, air velocity, temperature, humidity and fresh air volume. Some illustrations and considerations are shown too.

Compared with the international standards and design guidelines, the Chinese new design code has more detailed parameters for high level sports game.

Not all the indoor air parameters of the code are mentioned in this paper. The designs of sports building are built for high level sports games in recent years of China, the parameters of class A are paid more attention to in the paper.

The contents of paper could be the major designs in heating, ventilation and air conditioning system in sports building.

This paper could be a guide to advice the designing of indoor air environment of sports building, especially for the Beijing Olympic game in 2008, and is useful to help advanced HVAC design and analysis on the similar large space buildings.

The goal of this project was to develop practical strategies for preventing building‐related symptoms in office buildings, based on the experience of those who investigate buildings with health complaints, and suitable for use by those who own, lease, or manage office space.

Ideas from six experienced building investigators on primary causes and key prevention strategies were gathered and prioritized through consensus and voting in a structured, multi‐day workshop.

IEQ investigators from diverse climatic regions agreed on the most important problems causing symptom complaints in office buildings, and the key strategies for prevention. The top ranked problems identified were, in priority order: excessive building moisture, inadequate outdoor air, excessive dust, pollutant gases and odors, inadequate thermal control, and inadequate attention by management to indoor environments. The highest priority recommended prevention strategies for building‐related symptoms were: managing moisture at building exteriors, operating ventilation systems per design intent, providing at least the minimum recommended ventilation rates, and maintaining indoor temperatures at 72°F±2° (22°C±1°). Available scientific findings were generally consistent with these recommendations.

Validity of these findings, from a subjective synthesis of empirical knowledge, not from scientific research, has not yet been scientifically confirmed.

These recommendations, including managing moisture at building exteriors, providing adequate ventilation, and controlling indoor thermal conditions, provide practical, empirically based guidelines for those who own, manage, or maintain office buildings.

The empirical knowledge of practitioners, concentrated and synthesized here, offers more direct guidance for health‐protective strategies in office buildings than current science.

In order to clarify the determining features of approaches adopted in policies for regulating indoor air pollution, this paper analyzes case studies of the approaches taken, in four countries, to risk management of indoor air pollution caused by formaldehyde in housing.

We pursued case studies to provide historical perspectives on early warnings and actions taken in relation to suspected health hazards from exposure to formaldehyde, in Germany, the USA, Canada and Japan. Many investigations of indoor air pollution caused by formaldehyde in housing have been conducted, and regulations established, in these countries. We reviewed the vast quantity of literature and documents relating to governmental and/or industrial actions and of research on indoor air quality produced in the past 40 years, and compared the approaches adopted.

The study identified the differing character of the approaches adopted in policies for the regulation of indoor air pollution, in order to clarify the range of actions that may be taken in response to reported risk from indoor air pollutants and describe possible risk management models for indoor air pollution.

Understanding of the nature of approaches already adopted will help to preserve good indoor air quality and minimize health hazards due to indoor air pollution.

This paper identifies a range of actions that have been taken in response to suspected risk from indoor air pollutants, through the analysis of its case studies.

The purpose of this study is to evaluate the effect of the perimeter heating load about the air diffusion performance index (ADPI) and propose a selection guide for proper line diffuser when perimeter heating load exists.

A high sidewall line diffuser was installed into a test room following the ISO standard 5219. The velocity and temperature distributions and the ADPI values are obtained numerically with 12 cases when the air flow rates are 425, 730 and 950 CMH and the heating loads are 0, 25, 50 and 75 percent of the total heating load, 2,143 W.

The ADPI decreases according to the increases of the flow rate on every heat load ratio of the present study except 0.75 with the line diffuser installed at the high sidewall. And we produced ADPI curves when the sidewall heating load exists or not in the same air flow rate and supply conditions. From that, it is possible to assume that the throw length guarantees more than 80 percent of ADPI with heating load on the wall.

Further work by the authors is focusing on making of database of various other diffusers which are generally used in the field.

This paper provides a modified selection guide for proper sidewall line diffusers to field engineers when perimeter heating load exists on the walls.

To provide input data to design and energy performance calculations of buildings and ventilation, heating, cooling and lighting systems.

European directive for energy performance of buildings was approved in the beginning of 2003. The transition period is 3‐6 years depending on the article. European Standardisation Organisation (CEN) has drafted several standards to help the member countries implementing the directive. One of these is the “Criteria for the indoor environment including thermal, indoor air quality (ventilation) light and noise.” The standard has been developed based on existing international standards and guidelines for the indoor environment taken into account the latest results from published research.

The standard specifies design values of indoor environment, values to be used in energy calculations, and methods how to verify the specified indoor environment in the buildings. The paper describes some of the principles used in standards, and gives examples presented in the standard. The standard covers all building types but the paper is focuses on the non‐residential buildings, numeric examples are given only for offices.

The draft standard is under international review process during writing this paper, and subject to changes. The standard give default criteria for the indoor environmental parameters, which can be used if no national requirements are available.

This paper describes the indoor environmental parameters, which are important for people's health, comfort and energy consumption of buildings. This will help users to select more uniform input data for energy calculations.

A significant amount of work has been performed in the area of identification of factors affecting construction productivity. Previous studies have tried to determine the most important factors affecting construction productivity in different countries for a long time. As a result of continuous effort in this direction, researchers have identified a wide range of factors. While the subject area has matured, no general agreement could be made on the factors affecting construction productivity. To fill this gap, the purpose of this paper is to undertake a comprehensive systematic review of mainstream studies on factors affecting construction productivity published in the last 30 years (1986–2016).

A total of 46 articles from different sources such as journals, conference proceedings, dissertation and PhD theses were identified and thoroughly reviewed.

Gaps in research and practices are discussed and directions for future research have been proposed. The literature review indicates that despite noticeable differences in the socio-economic conditions across both developed countries and developing countries, an overall reasonable consensus exists on few significant factors impeding productivity. These are, namely, non-availability of materials, inadequate supervision, skill shortage, lack of proper tools and equipment and incomplete drawing and specifications. Nevertheless, implications of technology, site amenities, process studies, project culture, and impacts of physiological and psychological factors were not adequately covered in existing literature. The study also found that traditional construction projects have remained the main focus of these studies while green construction projects have been generally overlooked.

The review does not include studies that report productivity at the organisational or industry level as well as total factor productivity. The scope of the review is limited to work on identification of factors affecting productivity at the activity level in construction projects.

The outcomes of this study would help researchers and practitioners by providing the findings of previous studies in a concise manner. It is also expected that presenting a deeper and wider perspective of the research work performed until now will direct a more focussed approach on productivity improvement efforts in the construction industry.

This review paper undertakes a comprehensive systematic review of studies on identification of factors affecting construction productivity published during the last three decades.