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Abrasion of tires on road surfaces leads to the formation of tire and road wear particles (TRWPs). Approximately 5.9 million tonnes/year of TRWPs are emitted globally, and 12–20% of emissions generated on roads are transmitted into surface waters, where they can release (i.e., leach) chemical compounds that adversely affect aquatic species. To better understand the ecological risk of TRWPs, an acute, probabilistic ecological risk assessment model was developed and applied. This was a screening-level, conceptual ecological risk assessment (ERA) based on secondary data from published scientific studies. The model was demonstrated using British Columbia (BC) Highway 97 (TRWP source) and Kalamalka Lake (receiving water) in Canada, considering two spatial scenarios with varied highway (HWY) lengths and lake volumes. TRWP-derived chemical leachates considered for ERA were aniline, anthracene (ANT), benzo(a)pyrene (B(a)P), fluoranthene (Fl), mercaptobenzothiazole (MBT), and zinc (Zn). An assumed 'total TRWP-derived leachate set' was also assessed, representing all compounds present in tire-derived leachate test solutions. The results indicated the risk to aquatic species in two spatial scenarios. In scenario 1, ecotoxicity risk was high from exposure to TRWP-derived zinc and the total TRWP-derived leachate set. Scenario 2 results indicated acute risk was high from all TRWP-derived chemicals examined, except MBT. This preliminary ecological risk screening provides an early signal that freshwater lakes adjacent to busy highways may be at risk from TRWP contamination, indicating a need for further research. This research is the first ERA of TRWPs in Canada, and the results and methodology provide a foundation for future research and solutions development. [Display omitted] • Tire and road wear particles (TRWPs) are a major source of micropolymer • Ecological risk assessment (ERA) was conducted to assess the risk of TRWPs. • Two scenarios were developed by considering lake spatial factors. • The risk quotients for both scenarios ranged from 4.3E-05 to 2.5E+02. • ERA results can assist in minimizing the impacts of TRWPs in surface waters. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) has unprecedentedly entangled the physical world with cyber technologies and its integration with building infrastructure (BI) is no different. Integration of IoT can impart BI with upscale features like remote operations, automated management and user-centric facilities by developing an interconnected cognitive building (CB) ecosystem. However, this integration has entered an ambiguous phase of realizing mature adoption and practical utilization of IoT in BI for both academic and industrial domains. This ambiguity restricts the IoT and BI stakeholders to comprehend and acknowledge the full operational competency of IoT in BI. Thus, a significant research gap exists that deeply investigates the practical implementation and mature adoption of IoT in BI. The prime objective of this study is to establish a comprehensive review by exploring the state-of-art academic, technological and industrial research to identify major technological and behavioural interventions that successfully enhance the integration of IoT in BI. Besides, this study also highlights significant technical and non-technical challenges that require substantial research efforts for maturing the adoption of IoT in BI. The findings of the study argue that the full operational competency of IoT in BI is not yet realized and a dedicated effort from both IoT and BI stakeholders is required to provide modern BI with a generic IoT framework having cognitive intelligence and context-aware computing capabilities. The proposed study will assist the researchers in realizing the full operational competency of IoT in BI for more exciting innovations. • Adoption and implementation of IoT in building infrastructure are investigated. • Technological and behavioural interventions for cognitive intelligence in buildings. • Requirement of a seamlessly unified IoT framework for future buildings. • Trends, challenges and future research to effectively implement IoT in buildings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Renewable natural gas (RNG) can be produced from landfill gas, wastewater sludge, and animal waste. • Triple bottom line performance of waste-derived gaseous fuel was assessed using LCA and LCC. • Animal manure-derived RNG production provides the best environmental performance. • LFG-derived RNG yield the highest suitability from neutral and environmental perspectives. • RNG production suitability varies with regional conditions and decision contexts. Renewable natural gas (RNG) is one of the most prominent fuels that help reduce upstream emissions from conventional natural gas networks without significant infrastructure changes. While the current resources for RNG are insufficient, there is a substantial interest in establishing the viability of integrating RNG into the gaseous-fuel industry portfolio. However, holistic studies that support the assessment and selection of the fuel production paths are limited. Therefore, the current study attempts to close that gap by introducing a systematic approach to assess the project viability of RNG investments. Twelve waste-to-RNG configurations were evaluated based on three types of waste feedstock and four biogas upgrade technologies in three selected population centres. Life cycle environmental and life cycle cost assessment tools were employed to determine the ecological footprint and economic performance of RNG production routes. Multi-criteria decision-making was applied using the TOPSIS method under varying stakeholder perspectives to derive suitability indices for RNG investments. Finally, recommendations were provided based on the results obtained for successfully implementing waste-to-RNG supply chain paths. According to study findings, not all RNG production methods guarantee positive returns. The least environmental impacts were assured by the anaerobic digestion of animal manure. However, the lowest returns were obtained via the same route. From a pro-economic and neutral decision perspective, landfill gas-based RNG production achieved higher suitability scores. The proposed framework is flexible and can be customized to suit varying decision priorities. The findings are geared towards supporting utility providers, community developers, and potential investors to foresee the success of planned RNG projects to ensure sustainable gaseous fuel networks. [ABSTRACT FROM AUTHOR]

The global climate is being heavily affected by greenhouse gas (GHG) emissions, the most significant of which is carbon dioxide (CO 2). According to the Pan-Canadian framework on clean growth and climate change, Canada has set ambitious targets to realize a low carbon future. Amongst the available emission reduction strategies, on-site carbon capture, utilization, and storage (CCUS) is a proven technology capable of abating CO 2 emissions from fossil fuel-based energy systems. However, the viability of CCUS technologies is still uncertain and is subjected to numerous dynamic parameters. This study aims to assess the long-term economic viability of integrating carbon capture technologies into community emission planning. Key decision variables were identified, and the dynamic economic performance of CCUS investments was assessed for academic complexes located in two locations in Canada. A system dynamics model was developed to assess the future costs of carbon capturing projects. The study outcomes showed that CCUS is more feasible in provinces with high reliance on fossil fuel energy sources. Moreover, a significant portion of carbon capture costs is taken by infrastructure. Government policies have a critical role in accelerating the commercialization of CCUS technologies. The findings from this study are geared toward providing useful decision-support tools for policy experts, investors, and utility providers who are responsible for policy and investment decisions. Policymakers and investors will be benefited from the proposed model to develop customized regional policies and make investment decisions by considering dynamic regional aspects. Moreover, the results provide insight into what areas require attention in making CCUS economically viable. • System dynamics modelling can be used to predict carbon capture costs subjected to dynamic parameters. • Emission reduction with carbon capturing may change depending on regional parameters. • Carbon capture costs are sensitive to energy demand, grid composition, and carbon dioxide transport distances for utilization. • Community energy Infrastructure development and climate policies are essential in improving economies of carbon capturing technology. [ABSTRACT FROM AUTHOR]

Passive houses optimize energy gains and losses to attain higher energy efficiencies, comfort levels, and affordability. This article allows attaining a broader understanding of the risks and opportunities of passive technologies and their impacts through a social cost-benefit analysis framework. Time value of money was incorporated to evaluate the net present values (NPV), cost-benefit ratios, and internal rates of return. Five alternative houses consisting of passive and net-zero technologies were compared against a conventional design (traditional model). The base model with renewable energy integrations indicated higher impacts on the cumulative cost-benefits in economic, social, and environmental perspectives. Furthermore, a sensitivity analysis evaluated the effects of independent variables such as the interest rate and energy consumption on the performance metrics. This paper allows users to attain a holistic idea of implementing passive dwellings in a selected region through a social cost-benefit point of view. • A framework to evaluate passive house application for a region was developed. • Economic, social, environmental costs and benefits were considered in the framework. • Socio-environmental factors have a significant impact on the study's performance. • Incorporation of renewable energy provides higher benefits for the alternatives. • Passive houses increase overall benefits and decrease environmental impacts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sustainability of four waste-to-hydrogen conversion methods is evaluated. • Pyro-gasification and bioreactor landfills are assessed in hydrogen production. • Lifecycle thinking and VIKOR method-based multicriteria decision-making are used. • Reactor heating method, electricity mix, and waste transportation fuel are varied. • Gasification provides highest yields; pyrolysis causes lowest lifecycle impacts. Waste-derived hydrogen (H 2) has been identified as a clean energy source which could simultaneously abate greenhouse gas (GHG) emissions and avert municipal solid waste (MSW) from being deposited in perpetual landfills. In this study, four waste-to-hydrogen processes – gasification, pyrolysis, integrated pyrolysis-gasification, and landfill bioreactor technology – are studied with MSW as feedstock. Following technological evaluations, life cycle assessment and life cycle costing are performed for different scenarios and configurations to evaluate their environmental footprint, levelized cost of H 2 , and energy return on investment. Finally, multicriteria decision-making was applied using the VIKOR method under four weighting schemes to evaluate the four processes under varying decision-making contexts. Gasification results in the highest H 2 outputs and energy returns, whereas pyrolysis produces the lowest levelized cost due to its biochar by-product formation. Nevertheless, all four technologies proved to be performing optimally under different weightings of environmental, economic, and social elements, suggesting the versatility of the waste-to-hydrogen concept and its suitability to be applied in various decision-making contexts. The results and novelties of this study would contribute toward planning and investment decision-making in sustainable H 2 production and clean energy. [ABSTRACT FROM AUTHOR]

Urban densification has dominated the land uses and land covers which may jeopardize the quality of life and sustainable development. Moreover, urban densification process exerts stress on buried water infrastructure (BWI) performance. In this study, the need of predicting the change in urban densification and its subsequent impacts on BWI performance over time has drawn attention to conduct a temporal analysis. A hybrid approach was used to select the significant control performance indicators (CPIs) and conduct a temporal analysis. Eight scenarios were generated using the Canadian Council of the Ministers of the Environment Water Quality Index approach to address the change in drinking water quality. The proposed approach was implemented in a municipality of British Columbia, Canada, as a case study. The results showed a 40 % decrease in the BWI performance due to the urban areas have rapidly grown both in population and built-up areas over three decades. Furthermore, an ideal situation was assumed to show that the targeted service level (i.e., 0.5) can be achieved with 3 % to 5 % improvement in every five years of service level. These findings will assist the decision makers to understand the linkage between CPIs to maintain and achieve the required BWI performance. • Urban growth patterns and their impacts on buried water infrastructure (BWI) • Significant control performance indicators were selected using empirical models. • A hybrid approach coupled with water quality index is used for temporal analysis. • The proposed approach was applied to a municipality of British Columbia, Canada. • Over time, 40 % decrease was observed in BWI performance due to densification. [ABSTRACT FROM AUTHOR]

Construction and building industry is in dire need for developing sustainability assessment frameworks that can evaluate and integrate related environmental and socioeconomic impacts. This paper discusses an analytic hierarchy process (AHP) based sustainability evaluation framework for mid-rise residential buildings based on a broad range of environmental and socioeconomic criteria. Acradle to gravelife cycle assessment technique was applied to identify, classify, and assess triple bottom line (TBL) sustainability performance indicators of buildings. Then, the AHP was applied to aggregate the impacts into a unified sustainability index. The framework is demonstrated through a case study to investigate two six storey structural systems (i.e. concrete and wood) in Vancouver, Canada. The results of this paper show that the environmental performance of a building in Canada, even in regions with milder weather such as Vancouver, is highly dependent on service life energy, rather than structural materials. [ABSTRACT FROM AUTHOR]

Air emissions generated in grey cement manufacturing originate primarily from the combustion of fossil fuels required to heat the kiln and the chemical reaction of raw materials in the pyroprocessing phase. Given that the kiln system is enclosed, air emissions generated, discharge from a single point source kiln stack. Unlike other industries, the point source kiln stack enables the cement sector to accurately monitor and record total air emissions. The largest contributors to air emissions from grey cement manufacturing are carbon dioxide (CO), oxides of nitrogen (NO), sulphur dioxide (SO) and dust/particulate matter (PM). In Canada, grey cement manufacturing facilities are required to annually report these emissions through the National Pollutant Release Inventory (NPRI). Since CO, NO, SO and PM are the largest contributors to air emissions, and Canadian grey cement facilities are required to report these emissions, combining NPRI data with annual grey cement production data allows for the development of intensity-based environmental performance indicators. Based on data provided by NPRI, in combination with industry production, we can better understand the environmental performance of Canada's grey cement manufacturing. On the global stage, intensity-based performance measures provide a useful tool for comparison and demonstrate a strong environmental performance for grey cement production in Canada. As an energy intensive and trade exposed (EITE) grey cement manufacturing is vulnerable to unbalanced environmental policy, which may ultimately result in leakage of production and air emissions to developing countries. [ABSTRACT FROM AUTHOR]

Abstract: Covering a building envelope with green walls is considered a sustainable construction practice. Green walls can be classified as green facades or living walls based on their purpose and characteristics. Living walls are built with different layers and variable planting styles depending on the geographic location, function, and weather conditions. This paper discusses a comparative lifecycle assessment (LCA) of three living wall systems: trellis system, planter box system, and felt layer system. Chemical emissions and energy consumption of the living wall materials are evaluated in the whole lifecycle, and compared with the chemical absorption and energy savings of operational living walls. The results demonstrated that the felt layer system is not environmentally sustainable in air cleaning and energy saving compared to the trellis system and modular panel system. The environmental performance of living walls is influenced by the types of materials and plants chosen for the systems, as well as the external factors, such as climate and building type. The LCA indicates the need of environmental friendly materials for sustainable living walls. [Copyright &y& Elsevier]

Civil infrastructure systems are critical assets that are subjected to damage, service-life deterioration, and increasing maintenance and rehabilitation cost. Effective infrastructure management and principles of sustainable development can help to find an optimal compromise between economic growth and environmental protection for all stakeholders. Colloquially, sustainability refers to meeting triple-bottom-line (TBL) performance objectives including environmental protection, economic prosperity, and social acceptability and equity as a result of short- and long-term policy decisions. In this paper, a comprehensive framework based on the integration of emergy synthesis and life cycle assessment (LCA) has been investigated for a public infrastructure system. The main purpose of the applied method, emergy-based LCA (Em-LCA), is to facilitate an informed decision making process for different asset management scenarios, by identifying and quantifying the attributes of TBL impacts over the life cycle of a civil infrastructure system. As a case study, Em-LCA framework has been applied to evaluate the sustainability of two different scenarios for a road construction project in interior British Columbia, Canada. The results indicate that Em-LCA offers a good understanding to address sustainability issues in infrastructure systems and provides quantitative and transparent results to facilitate informed decision making for asset management. [ABSTRACT FROM AUTHOR]

Highlights: [•] Environmental impacts and benefits of RDF production and use have been assessed. [•] Economic costs and profits of RDF production and use have been evaluated. [•] Utilization of RDF as an alternative fuel in cement kilns has been investigated. [•] Environmental assessment has been conducted using a life cycle assessment (LCA) approach. [•] Cost–benefit analysis (CBA) has been carried out to study the economic factors. [Copyright &y& Elsevier]

Sustainable built environment has been of interest to many stakeholders in the recent years. However, life cycle economic performance as one of the key dimensions of sustainability has not been sufficiently investigated for buildings constructed using off-site construction methods such as modular construction. This research has proposed a framework to benchmark the life cycle economic sustainability of single-family modular homes. First, suitable economic performance criteria were selected and suitable measurable economic performance indicators were developed under each criterion. A performance level function was established for each indicator by which all indicators can be calculated and presented by a normalized performance level that enables combining quantitative and qualitative indicators. Subsequently, a multi-criteria decision analysis-based methodology was employed to develop a set of economic sustainability indices at the criteria level and also at the overall economic sustainability performance level. To compare and contrast the developed indices of a given modular building with the performance of similar conventional buildings, suitable performance benchmarks scales were established using the data of the historical economic performances of conventional homes. To examine the application of the proposed framework, two case study modular homes in British Columbia, Canada were analyzed. The results showed that both benchmarking homes performed 'Excellent' with respect to the overall economic sustainability. However, improvements are required to enhance the economic performance with respect to a number of criteria. The proposed framework can assist the construction decision makers, developers, and contractors with making informed decisions on the selection of the construction method. Furthermore, it can be used to address the underperforming areas over the life cycle of a modular building, even if the decision on the construction method has already been made. [ABSTRACT FROM AUTHOR]

The ever-increasing anthropogenic greenhouse gas (GHG) emissions worldwide make it quite challenging to meet country-specific Nationally Determined Contributions (NDC) targets. Therefore, it is evident that the existing emissions abatement measures need to be taken a step further. Internationally Transferred Mitigation Outcomes (ITMOs) are allowed in Article 6.2 of the Paris Agreement as a cooperative approach to achieving NDC goals. There is a potential to create ITMOs between Canada and China by replacing coal use in China with British Columbia (BC)'s liquefied natural gas (LNG) supply. Replacing coal with LNG in energy generation applications is a promising approach to mitigate emissions. With global and national pressures to reduce emissions, China has created a market for LNG imports to cater to its rising natural gas (NG) consumption due to the coal-to-gas source switching strategy. However, the terms under Article 6.2 requires generated ITMOs to ensure environmental integrity, support sustainable development goals, and have a robust accounting system. Therefore, the current study aims to quantify the life cycle environmental outcomes of generating ITMOs by exporting LNG from BC to Chinese end-users while integrating uncertainties and to provide policy recommendations in adherence with the requirements of Article 6.2. Different LNG export scenarios were generated in the study and environmental impacts of each scenario were assessed and compared using a life cycle assessment (LCA) framework developed by the authors. Sensitivity and uncertainty analyses were conducted to understand the impacts created by the data uncertainties in the final result. By replacing conventional coal with NG, approximately 40–45% and 26%–32% emissions reductions can be obtainable for Chinese textile and chemical industries, respectively. The highest emissions reduction of approximately 60% was observed when coal is replaced with NG for district heating. The life cycle emissions (LCE) quantification framework provided in the study provides stakeholders with a systematic approach to determine the total GHG emissions and emissions reduction potential of different LNG export scenarios. [ABSTRACT FROM AUTHOR]

Abstract: In North America, thousands of construction workers get injured and dozens die, on a yearly basis, due to work related injuries and illnesses. This reality prevailed from year 2000 to 2012 without a significant decrease. It seems that advanced health and safety regulations failed to make a positive impact. However, the use of information and communication technologies to improve safety is limited in the construction industry. This paper describes a system that transmits safety related information of multiple construction projects into a centralized database, where real-time safety indicators are generated. The system provides safety indicators related to an individual project or industry-wide figures. On site managers can use such real-time information for informed decisions in work sites. The system can also be accessed by the general public, research institutions, and regulating bodies, to formulate industry-wide safety standards and policies. The proposed system was pilot tested with positive and encouraging results. [Copyright &y& Elsevier]

Abstract: Organizational and people centered issues pose the greatest challenge for Building Information Modeling (BIM) implementation. Studies showed that BIM implementation is still a challenge for the North American construction industry. The Canadian construction industry, in contrast, is well behind that of the U.S. in its BIM adoption rate. Maturity and adoption of BIM depends mainly on the client or the owner in construction projects. Public sector clients often think that the market is not ready for BIM and are afraid to increase project costs by limiting competition. Moreover, if the contractor is not integrated in the project in the design phase, BIM has limited power. This paper proposes a ‘BIM partnering’ based public procurement framework to ensure ‘best value’ in construction projects. The case study presented in the paper proved the feasibility of proposed BIM based procurement in publicly-funded construction projects. The suggested contractual arrangement for the project resulted in improved productivity, better coordination, and reduced error, and rework. [Copyright &y& Elsevier]

Abstract: Sustainable regional management (development) requires an understanding of interactions between the social, economic, and ecological systems within the boundaries of a region. In this paper, application of emergy (an environmental accounting method) for regional planning is discussed through a case study. Emergy (spelled with an “m”) methodology is an environmental accounting technique that evaluates the energy system for the thermodynamics of an open system. Major renewable and non-renewable resource fluxes to a region, including energy, matter, human activities, and money can be converted to emergy by using corresponding transformity functions. As a case study, this paper discusses the emergy accounting of Canada and its provinces with various emergy-based indicators. Moreover, emergy maps were generated in a form of emergy geography. These maps are multi-dimensional illustrations that show resource consumption, emergy per person, and emergy density across Canada under two parameters: (1) the quantities of resources consumed and (2) the location of consumption. Emergy analysis also highlights concentrations of renewable and natural resources in Canada and distinguishes the provinces with the highest resource consumption. Analysis of emergy indicator for Canadian provinces shows that Alberta with the highest EYR (7.35) provides energy to the economy of Canada. However, ELR value of Alberta (8.5) indicates that the province''s current economic approach is not sustainable as it relies mainly on non-renewable emergy inputs (mainly from fossil fuels). ELR of British Columbia and Manitoba indicates that these two provinces created a firm balance between emergy use of renewable and non-renewable resources. The characterizations of regions provided in this paper can be used for future land planning and management both in federal and provincial levels. [Copyright &y& Elsevier]

The construction and demolition (C&D) waste generated by the Canadian construction industry accounts for 27 % of the total municipal solid waste disposed in landfills. However, it is evident that over 75 % of what the construction industry generates as waste has a residual value, and therefore could be recycled, salvaged and/or reused. The need for comprehensive and integrated waste management mechanisms, technologies, rating systems and policies is widely recognized. Owing to increasing C&D waste volumes, shortage of landfills and long-term adverse environmental, economic and social impacts of the disposed C&D waste, sustainable C&D waste management is becoming increasingly essential to protect public health and natural ecosystems. This paper proposes a conceptual C&D waste management framework to maximise the 3R (reduce, reuse and recycle) and minimise the disposal of construction waste by implementing sustainable and comprehensive strategy throughout the lifecycle of construction projects. In addition, a life cycle based C&D waste sustainability index is developed. This approach can be used to make decisions related to selection of material, sorting, recycle/reuse and treatment or disposal options for C&D waste. [ABSTRACT FROM AUTHOR]

Abstract: Green roofs have been used as an environmentally friendly product for many centuries and considered as a sustainable construction practice. Economic and environmental benefits of green roofs are already proven by many researchers. However, a lifecycle net benefit-cost analysis, with the social dimension, is still missing. Sustainable development requires quantitative estimates of the costs and benefits of current green technologies to encourage their use. This paper is based on an extensive literature review in multiple fields and reasonable assumptions for unavailable data. The Net Present Value (NPV) per unit of area of a green roof was assessed by considering the social-cost benefits that green roofs generate over their lifecycle. Two main types of green roofs – i.e. extensive and intensive – were analyzed. Additionally, an experimental extensive green roof, which replaced roof layers with construction and demolition waste (C&D), was assessed. A probabilistic analysis was performed to estimate the personal and social NPV and payback period of green roofs. Additionally, a sensitivity analysis was also conducted. The analysis demonstrated that green roofs are short-term investments in terms of net returns. In general, installing green roofs is a low risk investment. Furthermore, the probability of profits out of this technology is much higher than the potential financial losses. It is evident that the inclusion of social costs and benefits of green roofs improves their value. [Copyright &y& Elsevier]

Drinking water, wastewater, and stormwater are three components of an Urban Water System. Maintenance of these components requires evaluation of the existing performance of the water system. The evaluation becomes more significant in small and medium-sized water systems because these systems wrestle with various constraints, such as insufficient funds, inadequate infrastructure and water governance. In this study, Key Performance Indicators (KPIs) are identified for each UWS component considering six performance criteria. A questionnaire was distributed to water utilities across the Okanagan Valley. KPIs were identified by combining Delphi technique and Preference Ranking Organization Method for Enrichment Evaluation methods. Ninety-six KPIs were identified with 39, 30, and 27 KPIs for drinking water, wastewater, and stormwater. Based on the available literature, agriculture water use, low impact development implementation (LID), average annual life cycle investment, and swimming advisories are a few notable KPIs that are unique to the Valley. [ABSTRACT FROM AUTHOR]

The increasing number of studies covering different life cycle sustainability assessment (LCSA) tools and urban water systems (UWSs) emphasize the need to synthesize current research. While LCSA studies focus on an integrated approach considering the life cycle assessment (LCA), Life Cycle Costing (LCC), and social life cycle assessment (S-LCA) methodologies, these tools are typically applied separately, disregarding the trade-offs amongst economic, social, and environmental impacts. In this context, this review aims to critically analyze the literature on LCSA tools to enhance the integrated application in the future. Furthermore, we aim to identify technological trends, current challenges, and future research directions to improve sustainability. The ProKnow-C methodology was applied using a combination of four keyword sets and three databases. We selected 72 relevant papers that were analyzed in detail. Results demonstrate that authors apply different boundaries when using different LCSA tools, and lack of data was also a common issue. Furthermore, papers lack system description in the scope definition, leading to a biased interpretation of results. Another important issue was the functional unit selection, which did not represent the complexity of UWSs, lacking important details such as water loss, water quality, and population served. Water treatment is the most researched process in UWSs, and stormwater systems (collection or treatment) are rarely included, representing only 25% of the analyzed literature. In conclusion, the application of LCSA tools faces fundamental challenges, such as data quality and availability. Concerning the engineering improvements, future works should use LCSA data to support design and technology development, also focusing on human behaviour and frugal technology alternatives. Finally, new paradigms need to be developed and applied to enhance sustainability and integrate UWS. [ABSTRACT FROM AUTHOR]

Abstract: Green roofs can be classified as intensive and extensive roofs based on their purpose and characteristics. Green roofs are built with different layers and variable thicknesses depending on the roof type and/or weather conditions. Basic layers, from bottom to top, of green roof systems usually consists of a root barrier, drainage, filter, growing medium, and vegetation layer. There are many environmental and operational benefits of vegetated roofs. New technology enabled the use of low density polyethylene and polypropylene (polymers) materials with reduced weight on green roofs. This paper evaluates the environmental benefits of green roofs by comparing emissions of NO2, SO2, O3 and PM10 in green roof material manufacturing process, such as polymers, with the green roof’s pollution removal capacity. The analysis demonstrated that green roofs are sustainable products in long-term basis. In general, air pollution due to the polymer production process can be balanced by green roofs in 13–32 years. However, the manufacturing process of low density polyethylene and polypropylene has many other negative impacts to the environment than air pollution. It was evident that the current green roof materials needed to be replaced by more environmentally friendly and sustainable products. [Copyright &y& Elsevier]

A skill-measuring criterion or strategy can be used to optimize the scarce skilled labour force in the Canadian construction industry. The University of Calgary conducted an extensive study to assess the skill levels and team performance of field workers and managers in Alberta's building construction projects. Over 150 workers and field managers were interviewed, surveyed with questionnaires and observed, to identify team efficiencies, skill levels, team spirit, and team perceptions of supervision. The average construction worker had over 15 years of field experience. Most of the workers were high school educated. More than 70% of the workers wanted to improve their career skills; however, internal and external opportunities were limited and (or) not promoted by the respective construction companies. A very few foremen had certified skills in administration, computer handling, planning, job management and work records. The research clearly noted the urgent need for training programs, for workers and field managers, to improve their present skill levels. [ABSTRACT FROM AUTHOR]