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The purpose of this paper is to determine the usability of design reviews to inform designers about low carbon technologies and building performance. The design review of three domestic and two non-domestic case studies are evaluated.

Data collection and analysis methods include interviews and meetings with design teams and contractors, design tools audit and revision of drawings and project documentation. In addition, building's envelope and systems, and in-use performance evaluations are used to inform design teams about the actual performance of the buildings.

This study showed that targets and intentions defined in the design process are not always compatible or reality checked. These contradictions between targets within a project can undermine the performance of a building. The design review can identify unrealistic expectations to assess fairly the performance of buildings. The study showed that changes made during construction to the original design are related to lack of specifications or experience with low carbon technologies. Design reviews can help designers to identify the knowledge gaps within their practice. Furthermore, the results showed that building-related energy consumption was close to expectations, while user-related consumption was higher than expected due to occupancy assumptions made during the design. The design review showed that designers require more knowledge about buildings’ in-use performance in order to take informed-based design decisions.

This paper showed the main stages of a design review, and their usability to assess building performance and to inform designers. The results of this study suggest that designs can benefit from design reviews by learning about low carbon technologies installation and building's operation.

Accurate values for infiltration rate are important to reliably estimate heat losses from buildings. Infiltration rate is rarely measured directly, and instead is usually estimated using algorithms or data from fan pressurisation tests. However, there is growing evidence that the commonly used methods for estimating infiltration rate are inaccurate in UK dwellings. Furthermore, most prior research was conducted during the winter season or relies on single measurements in each dwelling. Infiltration rates also affect the likelihood and severity of summertime overheating. The purpose of this work is to measure infiltration rates in summer, to compare this to different infiltration estimation methods, and to quantify the differences.

Fifteen whole house tracer gas tests were undertaken in the same test house during spring and summer to measure the whole building infiltration rate. Eleven infiltration estimation methods were used to predict infiltration rate, and these were compared to the measured values. Most, but not all, infiltration estimation methods relied on data from fan pressurisation (blower door) tests. A further four tracer gas tests were also done with trickle vents open to allow for comment on indoor air quality, but not compared to infiltration estimation methods.

The eleven estimation methods predicted infiltration rates between 64 and 208% higher than measured. The ASHRAE Enhanced derived infiltration rate (0.41 ach) was closest to the measured value of 0.25 ach, but still significantly different. The infiltration rate predicted by the “divide-by-20” rule of thumb, which is commonly used in the UK, was second furthest from the measured value at 0.73 ach. Indoor air quality is likely to be unsatisfactory in summer when windows are closed, even if trickle vents are open.

The findings have implications for those using dynamic thermal modelling to predict summertime overheating who, in the absence of a directly measured value for infiltration rate (i.e. by tracer gas), currently commonly use infiltration estimation methods such as the “divide-by-20” rule. Therefore, infiltration may be overestimated resulting in overheating risk and indoor air quality being incorrectly predicted.

Direct measurement of air infiltration rate is rare, especially multiple tests in a single home. Past measurements have invariably focused on the winter heating season. This work is original in that the tracer gas technique used to measure infiltration rate many times in a single dwelling during the summer. This work is also original in that it quantifies both the infiltration rate and its variability, and compares these to values produced by eleven infiltration estimation methods.

Attention has been increasingly devoted to the development of methods for assessing the quality of care in long‐term care (LTC) facilities, especially for government surveillance. A study is described which used the tracer method to provide data on the quality of care in Israeli LTC institutions. Advantages of the tracer method include its incorporation of structural, process and outcome measures and its focus on a number of representative tracer conditions. The study tested the ability of the tracer method to provide data on the quality of care, and facilitated adoption of this methodology by the government for their annual inspections.

This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance.

Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method.

RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal.

A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

ALTHOUGH the radioactive tracer technique has been known for many years, it is only recently that the production of a wide variety of artificially produced radioactive isotopes has opened up this field of research to all industries. Many firms may be prejudiced against adopting this new technique, because of possible dangers to personnel, lack of trained staff or an inadequate knowledge of the subject, but in many cases the advantages over ordinary methods are so great that it is worth while overcoming these prejudices.

The purpose of this paper is to review traditional hermeticity test methods when applied to typical micro‐electro‐mechanical systems (MEMS) cavity volumes and to propose potential solutions.

Standards for traditional testing have been applied to typical MEMS cavity volumes and the resulting issues of range and sensitivity discussed. In situ test structures have been designed and fabricated with access to the internal cavities to allow characterisation of the structures as a function of pressure.

The ultra low leak rates necessary to guarantee hermeticity of MEMS cannot be measured using traditional methods. Optical test methods are possible although in situ test structures currently provide the greatest sensitivity. A portfolio of test techniques is required to allow accurate hermeticity testing of MEMS.

This paper provides a starting point for further investigation into several methods of MEMS hermeticity testing.

This paper provides a review of the limitations of traditional testing and proposals for future testing as the trend towards smaller volume packaging continues.

Describes the testing and lubricating mechanisms of Slick 50, a solid lubricant engine oil additive containing PTFE for reducing friction and wear. Gives the results of long term engine tests by the Southwest Research Institute, Texas, monitored by radioactive tracer, exhaust emission analysis and fuel economy improvement. Offers Slick 50 as an alternative to zinc phosphorus additives.

Increasing awareness of the consequences of device failures has resulted in increased reliance on Environmental Testing as an additional means of enhancing the integrity and reliability of a device. The key consideration is not the cost of the device itself, but the cost of subsequent failure, which can be as much as a hundred times greater. Seal tests are undertaken to ensure that moisture cannot get into the internal cavities of sealed ceramic, metal or glass packages. Seal security is vital to the long‐term reliability of all hermetically sealed devices. This paper outlines the techniques involved and the requirements of the MIL, BS and IEC specifications.

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.