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Building airtightness is a critical aspect for energy-efficient buildings as the energy performance of a building can be significantly reduced by poor airtightness. The Pulse technique has been regarded as a promising technology, measuring building airtightness at a low pressure of 4 Pa. However, due to the rapid dynamic nature of the test, a frequently raised question concerns the uniformity of the pressure distribution across the internal space of the test building during the air pulse release. In order to investigate this point, experimental work was conducted in a five-bedroom dwelling. All the tests were conducted at wind speeds less than 0.45 m/s to minimise the wind impact on the indoor pressure. The results show a pressure difference within the building during the Pulse test does exist, but considering the accuracy of differential pressure transducers, the deviation is not significant. In addition, a subtle variation is noted when the Pulse test was conducted at different locations on the ground floor, which may also be caused by variations in the environmental conditions. In terms of the airtightness measurement, a good overall agreement was found between the Pulse technique and the conventional blower door fan pressurisation method, which indirectly verified the uniformity of the indoor pressure distribution during both tests. Moreover, the error analysis demonstrated the validity of the measurement results for the two test methods in this study.

Buildings are responsible for 40% of the global energy usage to which infiltration-caused heat losses are responsible for 30%. Air infiltration is the unintended flow of air through leakage paths and fundamentally determined by the airtightness of a building. In the United Kingdom, building airtightness is conventionally measured through a blower door test and used to predict air infiltration in conjunction with the divided-by-20 rule, which is a rule of thumb that has been adopted by SAP (Standard Assessment Procedure: a UK government's recommended method system for measuring the energy rating of residential dwellings) for the estimation of the infiltration-caused heat losses for dwellings. This paper assesses the representativeness of this rule of thumb by carrying out blower door and tracer gas tests in twenty one dwellings located in the East Midlands Region of the United Kingdom. Results showed that a divide-by-37 rule would be more representative. It was also seen that the air infiltration rate is overestimated by SAP when modifying factors are added. The errors are as high as 500% in some cases. The most affected dwellings were the tighter ones. A revision of the usage of the divide-by-20 rule and the modifying factors is advised.

This paper introduces a comparison study of measuring the airtightness of a house-sized test chamber using the novel pulse technique and a low range blower door method in a sheltered environment. Eight different testing plates were prepared and applied to the improvised envelope of the chamber to establish different leakage characteristics. Each testing plate has a unique opening in its centre, achieved by obtaining different combinations of shape and thickness of the opening. By using the sheltered environment, the vagaries of the natural condition when testing within buildings have been reduced providing a more robust testing environment. This investigation focuses on how the air leakage rate calculated from the measurements made by both techniques compare with each other. Comparable results (0–5.3%) under most scenarios have been obtained. Larger discrepancies (14.6% and 21.8%) were observed in the two airtight scenarios due to insufficient pressure range achieved in a standard pulse test. This finding guided further improvement on the testing performance. Further pulse tests under different scenarios, involving the use of an internal barrier and various locations of the pulse unit were also performed to investigate the uniform pressure distribution and resilience to external interferences. It showed the internal barrier and location had minor impact (1.62%–4.65%) on the test results.

A pulse pressurisation technique is developed and utilised for determining building leakage at low pressure, based on a “quasi-steady pulse” concept. The underlying principle of the technique is to subject the building envelope to a known volume change in a short period of time (typically 1.5 s). The resulting pressure pulse is recorded, from which the leakage characteristic at low pressure is determined. The technique minimizes the effects of wind and buoyancy forces and has proven to be repeatable. It can use a compact and portable test rig and does not need to penetrate the building envelope. Therefore, it can obtain the leakage of a building very quickly and efficiently. Throughout the various stages of research and development of the pulse technique, experimental investigations have been carried out under different configurations and scenarios in order to validate the changes that have been made for the purpose of system development and optimisation. This paper provides an overview of experimental investigations in the validation process by covering comparison between blower door and pulse unit, comparison between piston-based pulse unit and nozzle-based pulse unit, testing with multiple pulse units in a large building, testing with a known opening, and testing in different building types with a range of volumes and airtightness levels. It enables us to understand the strengths and the limits of the pulse technique, from the experimental and practical perspectives. A good repeatability level (within ±5%) has been maintained throughout the various developmental stages and the average value of Q50/Q4 reported herein was in close agreement (

Motivated by intentions of avoiding large net fluid flow and enabling a more practical airtightness test for large buildings, a low-pressure Pulse pressurisation technique was developed for measuring building airtightness at pressures that are considered more representative of that experienced by buildings under natural conditions. Due to the short and dynamic operation, this technique is able to minimize wind and buoyancy effects during the measurement of building pressure. The investigation, based on the “quasi-steady” temporal inertia model, explores a technique that generates a pressure pulse inside a building by releasing a known amount of air pulse over 1.5 s using a compressed air tank. The volumetric flow rate of the air pulse released from the tank is obtained by measuring the transient pressure in the air tank during a test run. The air leakage through the building envelope is then obtained by accounting for the compressibility of indoor air. Simultaneously, the pressure variation within the envelope of test building is monitored. Therefore, the leakage-pressure relationship of the building envelope can be obtained. The validity of the theoretical model and the assumptions on which the model is based are validated using experimental and numerical investigations.

Air infiltration, occurring through gaps in the building envelope, can contribute up to one third of total heat losses associated with older UK dwellings [1]. Therefore, reducing the rate of air leakage (i.e. improving air ‘tightness’) can have a positive effect in terms of decreasing space heating requirements. This study presents an investigation of the effectiveness of airtightness measures applied in a retrofit context to a UK dwelling. A phased programme of refurbishment work was undertaken to a test dwelling at the University of Nottingham campus, UK. Evaluation techniques, including building energy modelling (SAP 2009), air pressurisation tests and thermal imaging, were performed. The study demonstrates that the use of conventional draught-proofing measures can achieve a reduction in air permeability of over 30% when compared with the house base case value of 15.57 m 3 /(h.m 2 ) @ 50 Pa. This reduction was only achievable with close attention to installation detail. Further measures of service penetration and floor sealing enabled the air permeability to be reduced to as low as 4.74 m 3 /(h m 2 ) @ 50 Pa. Modelling of the test dwelling predicted an initial space heating supply energy requirement of 32,373 kWh, which was reduced to 23,197 kWh by a combination of the air tightness measures, insulation, and system (boiler and ventilation) improvements. Air tightness measures alone contributed to approximately 9% of the predicted total reduction, half of which was due to relatively straight-forward draught-proofing. Other more advanced air tightness measures were considerably more expensive, though cheaper approaches to their application could help reduce payback times.

As a continued investigation following the previous testing of a house-sized chamber in a sheltered environment, this paper introduces an experimental study of airtightness measurement of an outdoor chamber using both the novel Pulse technique and the steady pressurisation method. The chamber has dimensions of approximately half that of a standard 20 ft long shipping container. The chamber's envelope was modified with multiple openings to provide a leakage level similar to that of an average UK house. Two sets of experimental tests were carried out independently at different times to investigate: a) How both methods compare on measuring the airtightness of an outdoor chamber at various leakage levels; and b) How the steady wind at various wind speed may affect the Pulse measurement of the chamber airtightness. Results show that the air permeability at 4 Pa measured by both methods has a percentage difference less than 16% in most testing scenarios, which is a slightly larger discrepancy than that found in the sheltered environment study. In steady wind tests, artificial wind at various speed levels was introduced in the Pulse tests by utilising a multi-gear portable trailer fan. Initial findings have shown that the impact of steady wind on the Pulse test is mostly insignificant when it is under 3.5 m/s. However, high wind speeds (4 m/s-9.5 m/s) decrease the value of air permeability at 4 Pa by 16%–24% in comparison to that measured under the fan-off condition in the steady wind tests.

This paper reviews policies relating to planning and pollution control – their drivers, their implementation and the challenges they face. Throughout the 30 years since the Royal Commission on Environmental Pollution reported on the use of planning controls over air pollution, the UK government's position has been characterised by ambivalence: urging the use of planning powers to control pollution while warning them to avoid encroaching on the remit of other regulatory agencies. While the language of planning controls over pollution and the pollutants of most concern have changed over the years, the role of planning in mitigating pollution must now be understood within the context of adaptation to European environmental policy, to recurrent demands for deregulation and, above all, to the pursuit of sustainable development. The paper argues that inadequate weight is given to pollution prevention in determining planning applications because of central government's reluctance to allow local planning authorit...

The widespread experience of environmental impact assessment (EIA) as an anticipatory environmental management tool has generated a considerable debate over the extent to which it is achieving its purposes. This has been measured in terms of EIA ‘effectiveness’, especially as discussion has moved away from issues of procedural implementation, to the more substantive goals of EIA and its place within broader decision-making contexts. Empirical studies have revealed the relatively weak degree of influence on planning decisions that is being exerted by EIA, which is increasingly being attributed to its rationalist beginnings. This article seeks to direct this debate towards the founding political purposes of EIA which, it is argued, provide a neglected, yet strong, basis for EIA reform. A number of illustrative suggestions are made as a result of this redirection, to enable EIA to adopt a more determinative role in decision making and to contribute to more sustainable patterns of development planning.

This article explores the nature of public participation in the environmental impact assessment (EIA) process in the context of the potential integration of the Aarhus Convention principles into the UK EIA system. Although the Convention advocates ‘early’ and ‘effective’ participation, these terms remain undefined and questions persist about exactly how to implement the Aarhus principles. Ten practice evaluation criteria derived from the Aarhus Convention are used to analyse the public participation procedures used in four UK waste disposal EIA case studies. The paper reports the extent to which the practice evaluation criteria were fulfilled, explores the types and effectiveness of the participation methods used in the EIAs, and highlights some of the key barriers that appear to impede the execution of ‘early’ and ‘effective’ participation programmes. It concludes that the Aarhus Convention will undoubtedly lead to a strengthening of participation procedures but that the level of improvement secured will depend upon how its ideals are interpreted and incorporated into legislation and practice.

Structure Plan appraisal reports provide valuable insights into the appraisal practices of English county councils. This paper presents the findings of an examination of evidence of the inclusion of a number of key good practice appraisal elements within 40 Structure Plan appraisal reports. The results are used to provide an assessment of the 'process quality' of Structure Plan appraisal practice since 1995. The methodological requirements of the European SEA Directive, which will soon apply to Structure Plans, provide a useful context for discussing the results of this study. The perspectives of relevant experts concerning good practice appraisal techniques are used as a further benchmark from which to draw conclusions. The results of the examination suggest that the process quality of Structure Plan appraisals falls short of meeting the methodological requirements of the Directive, and of experts, perspectives of good practice appraisal procedures. Several reasons are proposed to explain this situation,...

Developing country environmental impact assessment (EIA) dates back to the mid-1970s and, although it varies significantly from country to country, its performance generally falls far behind that of EIA in developed countries. It is crucial that this performance be improved in order to help to protect the environment of three-quarters of the world's land area. This paper reviews developing country EIA against a set of robust evaluation criteria to determine its strengths and weaknesses. The criteria relate to legal basis; coverage; consideration of alternatives; screening; scoping; EIA report preparation; EIA report review; decision making; impact monitoring; mitigation; consultation and participation; system monitoring; costs and benefits; and strategic environmental assessment (SEA). Developing country EIA meets few of the 14 evaluation criteria, and recommendations relating to each are advanced. Urgent generic issues relating to training and capacity building, diffusion of EIA experience, donor policy ...

The Countryside Agency has recommended that national park authorities (NPAs) undertake an environmental appraisal of their national park management plans. A study of the appraisal practices of the NPAs of England and Wales has shown that, despite this guidance, the practice of environmental appraisal is uncommon but that a culture of applying sustainability appraisal is evolving. It is argued that the most likely explanation for this situation is the increasing influence of the concept of sustainable development on the workings of the national park management system. This broad policy development has manifested itself in a variety of ways, including the production of government guidance relating to sustainability appraisal and changes in best practice, each of which have influenced appraisal procedures in national parks. The wider implications of, and drivers behind, the evolution of appraisal procedure towards sustainability appraisal are thus identified and then discussed.

This article reviews and compares the performance of environmental impact assessment (EIA) systems in three jurisdictions in the Middle East and North Africa region: Egypt, Turkey (Middle East) and Tunisia (North Africa). The EIA systems of these three jurisdictions are at a similar stage of development, with those of Turkey and Tunisia being the first to be introduced. EIA ‘systemic measure’ and ‘foundation measure’ criteria are used to evaluate the performance of each of the systems and to compare them. These criteria are partially based on evaluation and quality control criteria derived from a number of literature sources. The paper identifies similarities and differences in the performance of the three EIA systems and in the attempts undertaken by each of the three jurisdictions to strengthen their respective EIA systems. Recommended measures to increase the effectiveness of each of the EIA systems are also identified.

An analysis of existing (broadly defined) strategic environmental assessments (SEAs) in the spatial/land-use and transport sectors in England, the Netherlands, and Germany concludes that substantial practice exists and that three assessment types can be distinguished, each associated with distinct methodological tasks. By utilising existing terminology, these can be labelled policy-SEA, plan-SEA, and programme-SEA. It appears from current practice that, in order best to meet performance criteria derived from the SEA literature, these three types of SEA should be applied within a tiered system. Although the recently adopted EC SEA Directive includes provisions for the SEA of plans and programmes, the analysis of current assessment practice indicates that consideration should be given to extending the formal requirements to cover the SEA of policies as certain tasks are probably better dealt with in policy-SEA than in plan-SEA or programme-SEA.

This paper presents the results from a post-auditing study-a comparison of the predictions of environmental impacts of projects made in environmental statements prior to developmentwith those that actually occurred upon or after development. The purpose of post-auditing is to provide an analysis of prediction performance in environmental impact assessment and thus to improve future practice by learning from experience. By means of a combination of site visits, interviews and document scrutiny, 865 predictions from 28 UK projects granted planning permission were examined. Of these, 488 (56%) were auditable, of which 383 (79%) were deemed 'accurate' or 'nearly accurate' and 105 (21%) 'inaccurate'. The remaining 377 (44%) predictions were not auditable, the main reasons being lack of data, vague or ambiguous predictions and time dependency.There were only six unpredicted impacts. The study reveals some encouraging findings, but also a number of discouraging ones, which indicate the need to increase both enth...

An evaluation of the quality of environmental impact assessment (EIA) reports, modifications to projects as a result of EIA, and the influence of changes to EIA procedures in the United Kingdom, Germany, Spain, Belgium, Denmark, Greece, Ireland, and Portugal is reported. The overall proportion of “satisfactory” EIA reports sampled increased from 50% to 71% between 1990–1991 and 1994–1996. Several modifications to projects occurred as a result of the EIA process, but there was no apparent trend over time relating to the number or significance of modifications. All the eight Member States had taken major or minor measures to modify EIA procedures and these either have already improved the quality of EIA practice or are expected to do so. A series of recommendations to improve the performance of the EIA process is presented.

In this paper, current practice in the environmental appraisal of development plans in England and Wales is examined. The results of a detailed study of fourteen local authorities are presented. A comparative analysis of local authority practice demonstrates that there are considerable variations in the extent to which environmental appraisals have been carried out and that there are no universal standards against which the appraisals can be compared. The existing guidance on the environmental appraisal of development plans available in England and Wales appears to be an important starting point for many local authorities in the preparation of their own appraisals but this guidance is being superseded in some authorities. A proposed European directive is likely to require practice in the environmental appraisal of UK development plans to be strengthened. Suggestions for improving the environmental appraisal of development plans in the future are advanced. (A)

(1997). The Effect of Environmental Assessment on UK Infrastructure Project Planning Decisions. Planning Practice & Research: Vol. 12, No. 3, pp. 223-238.

This article reports the findings of an investigation of the practice of environmental impact assessment (EIA) for wastewater treatment plants in the United Kingdom and Germany. It demonstrates that both EIA systems have a number of common deficiencies but that the differences between the practice of EIA in Britain and Germany are considerable. These indicate that one of the objectives of the European Directive—to harmonize environmental controls—has not been met. The differences can be explained by examining: (1) the context in which EIAs for wastewater treatment plants take place in both countries; (2) the ways in which EIA procedures are implemented in both countries; and (3) the attitudes of the competent authorities in both countries to EIA.

Since the implementation of the environmental assessment (EA) regulations in 1988, there has been an observed increase in the number of environmental statements (ESs) being submitted to local planning authorities (LPAs) in the UK. There has also been an increase in the number of planning applications that are being submitted with supporting planning statements that contain some elements of EA (informal EA reports). These supporting statements are, however, not being submitted as formal ESs and are, therefore, not subject to the special requirements of the EA regulations. This paper examines the contents of these two types of documents and compares how they are used by LPAs in the Greater Manchester area. The Lee and Colley Review Package is used to review a sample of five ESs and five informal EA reports that were submitted to three LPAs in the Greater Manchester area between 1989 and 1992, and a comparison is made between the quality of the two types of document. Interviews with the relevant planning officers and questionnaire surveys of the developers and statutory consultees are used to compare the way in which the two types of document are prepared and used in the determination of planning applications. In practice, there are many similarities in the use of the two types of document, and the majority of the LPAs believe that both types of statement are an aid to decision-making. Deficiencies in current EA practice are discussed and a number of recommendations for improvement is suggested.

Western Australia introduced second-generation environmental impact assessment (EIA) with a comprehensive statutory backing upon the enactment of the Environmental Protection Act 1986. The outstanding characteristics of the EIA system are twofold: first among which is the primacy of the environmental decision, taken by the minister for the environment on the basis of the EIA process, over all other decisions and the implementation of the conditions attached to permissions as a result of the EIA process under the enabling legislation. Second is the statutory guarantee of independence from political direction that is enjoyed by the Environmental Protection Authority established, in part, to administer the EIA process. This study suggests criteria to evaluate the formal legal procedures, the arrangements for their application, and practice in their implementation in any EIA system and uses these to determine whether Western Australia's EIA system i worthy of emulation.

Studies of two samples of 24 selected local planning authorities (LPAs) in the UK were undertaken to determine the effect of environmental assessment (EA) regulations on planning practice during their first 18 months of operation. EA has been integrated into the UK planning system without significant recourse to the courts and many LPAs regarded EA as a worthwhile and helpful procedure. However, several LPAs did not consider whether to request EA for projects that might be likely to have significant impacts and some LPAs did not follow statutory and recommended consultation procedures. LPAs did not evaluate environmental statements systematically and their quality was often unsatisfactory. However, mitigation of environmental impacts took place in many cases though two‐fifths of the 20 determined applications involving EA were refused. Half the decisions took longer than the 16‐week time limit. While practice is evolving as experience is gained, there is obvious scope for further improvement and ...

The well-established environmental impact assessment requirements in the United States have given rise to a number of training needs within federal and state agencies. Requirements for training vary for EIA project managers, technical specialists, senior managers and others involved in EIA. Information needs about EIA vary also, but include general awareness, procedural knowledge, substantive methodological knowledge and technical knowledge. While EIA training is provided in short courses, on the job, and in universities there remain deficiencies in the training of specialists, senior managers, and others. Proposals are made here to help overcome these. This paper examines the needs and provisions for training in environmental impact assessment (EIA) in the USA federal system and in the system created by the California Environmental Quality Act. The investigation is based on the very limited literature on training, on responses to letters, on the printed material requested from agencies and, most importantly, on the results of a series of interviews of personnel in various federal agencies at central and regional levels, in California, and elsewhere. A recent report by the Environmental Law Institute (1981) furnished invaluable background information on EIA training in the federal agencies. The list of liaison officers printed by the Council on Environmental Quality (1982a) was used to request interviews and information.