scholarly journals The effect of the airflow pattern inside air gaps on the assessment of interstitial mould: A theoretical approach

2021 ◽  
pp. 014362442110204
Author(s):  
Spyridon Efthymiopoulos ◽  
Hector Altamirano ◽  
Yasemin Didem Aktas
Keyword(s):  
Feasible Solution ◽  
Dynamic Pressure ◽  
Unintended Consequences ◽  
Heat Losses ◽  
International Standards ◽  
Confined Space ◽  
Mould Growth ◽  
Internal Wall ◽  
Building Stock ◽  
Airflow Pattern

Internal wall insulation is one of the few, possibly, the only feasible solution to efficiently reduce heat losses through the external walls of buildings where the application of external insulation is not an option, for example, in conservation areas. However, the application of this intervention may lead to unintended consequences, such as moisture accumulation and mould growth. Currently, no international standards and regulations exist to evaluate these hazards via non-destructive inspections. Air sampling through impaction and culture-based analysis was suggested in previous research as a potential non-disruptive methodology for interstitial mould testing. The method requires the perforation of the inner side of a wall and the creation of airflow through the operation of a pump, to allow the collection of particles from the confined space of interest. The present study aimed to assess the location of perforations and their effect on the airflow created and the airflow pattern variations due to changes in the airflow velocity at the outlet. Results regarding airflow features such as the turbulence intensity, dynamic pressure and volume-averaged velocity were also extracted and discussed. Practical application: The rapid changes in climate and net-zero emissions targets call for major improvements of the existing building stock towards a more sustainable future. The installation of internal wall insulation is one of the few and might be the only feasible solution for the efficient reduction of heat losses through uninsulated walls. However, this intervention might lead to moisture accumulation and thus moisture-related problems such as mould growth. This study aims to build upon previous work on interstitial mould growth assessment and contribute to the development of a well-defined testing protocol for building professionals.

scholarly journals Confusion Reigns: An Analysis of Responses to U.S. Soccer Age Cut-Off Date Policy Change

2021 ◽  
Vol 3 ◽  
Author(s):  
Kristy L. Smith ◽  
Sara Scarfone ◽  
Laura Chittle ◽  
Sean Horton ◽  
Jess C. Dixon
Keyword(s):  
Social Media ◽  
Policy Change ◽  
Qualitative Content Analysis ◽  
National Level ◽  
Unintended Consequences ◽  
International Standards ◽  
Youth Soccer ◽  
Relative Age ◽  
Stakeholder Input ◽  
The U.S

Relative age effects (RAEs) have been associated with the common practice of grouping athletes by chronological age. Development and selection advantages are often awarded to those who are born closer to, but following, the cut-off date employed by sport systems. In 2015, the U.S. Soccer Federation announced that it would be changing its birth-year registration cut-off date from August 1st to January 1st. This change was introduced to align the U.S. youth soccer calendar with international standards, and simultaneously provide clearer information on player birthdates to “lessen” RAEs. The magnitude of this policy change has led to considerable controversy, with members of the soccer community taking to social media and website blogs, as well as the U.S. Youth Soccer's website, to voice their opinions and general unhappiness with this decision. Thus, the purpose of this study was to provide a summary of online reactions to the policy change, with attention to the manner in which the U.S. Soccer Federation framed (i.e., the underlying rationale for the decision) and publicly communicated its decision to change the annual cut-off date. Qualitative content analysis was used to analyze data collected from 63 social media sites (websites, n = 43; forums, n = 16; blogs, n = 4). From the 3,851 pages of text derived from these sources, a total of 404 unique passages of text were identified within 262 stakeholder posts. Four categories emerged from the data: stakeholder discussion, outcomes identified by stakeholders, recommended courses of action, and communication regarding the policy change. In general, the actions of the U.S. Soccer Federation and related outcomes were negatively perceived by stakeholders at various levels of the sport. Resistance to the change may have been reduced through enhanced communication from the national level and opportunities for stakeholder input. While one objective of this policy change was to combat RAEs, previous research suggests this organizational change will only shift which group of athletes experience relative age (dis)advantages. There appears to be a disconnect between the academic literature and sport policy with respect to solutions for RAEs, which can lead to unintended consequences for various sport stakeholders.

scholarly journals Normal background levels of air and surface mould reserve in English residential building stock: A preliminary study towards benchmarks based on NAHA measurements

2020 ◽  
Author(s):  
Yasemin Didem Aktas ◽  
Yasemin Didem Aktas ◽  
Yasemin Didem Aktas ◽  
Yasemin Didem Aktas ◽  
Yasemin Didem Aktas ◽  
...  
Keyword(s):  
Indoor Environment ◽  
Surface Cleaning ◽  
National Standards ◽  
Mould Growth ◽  
Building Stock ◽  
Local Climate ◽  
Background Levels ◽  
Water Damage ◽  
Normal Background ◽  
Indoor Mould

This paper reports results obtained from a surface (both visually clean and dirty/dusty surfaces) and active (aggressive or activated) air testing scheme on 140 residential rooms in England, without visible water damage or mould growth, along with a few rooms with visible mould growth/water damage tested for comparison purposes. The aim is to establish normal background levels of mould in non-water-damaged interiors to benchmark a normal indoor environment, and in turn when there is a need for further investigation, and, possibly, remediation. Air and surface mould was quantified based on the activity of β-N-acetylhexosaminidase (EC 3.2.1.52; NAHA). The obtained readings showed a log-normal distribution. 98% of the samples obtained from visually clean surfaces were equal to or less than 25 relative fluorescence units (RFU), which is suggested to be the higher bound for the range which can be used as a success criterion for surface cleaning/remediation in non-problem buildings. Of samples obtained from visually dirty/dusty surfaces, around 98% were below 450 RFU, which is suggested to define the lower-bound for abnormally high levels of mould, rare even on dirty/dusty surfaces. Similarly, around 98% of the air samples were found to have 1700 RFU or below. Values above 1700 RFU are therefore deemed unlikely in a non-problem indoor environment and can be indicative of a possible problem inducing mould growth. The samples with values below 1700 were further divided into three proposed sub-categories. Finally, the obtained RFU values and the suggested benchmarks were compared to those obtained from 17 non-residential indoor environments in Copenhagen tested previously, and the benchmarks that are currently used in Danish national standards, and they were both found to be highly congruent, suggesting that local climate regimes and room functions might not be as influential on indoor mould levels as commonly thought, or that the nuances between England and Denmark in terms of these factors are not strong enough to lead to sizable changes in the typical indoor mould levels in these countries.

scholarly journals Energy Efficiency, Thermal Comfort, and Heritage Conservation in Residential Historic Buildings as Dynamic and Systemic Socio-Cultural Practices

Atmosphere ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 604 ◽  
Author(s):  
Kalliopi Fouseki ◽  
David Newton ◽  
Krisangella Sofia Murillo Camacho ◽  
Sohini Nandi ◽  
Theodora Koukou
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Thematic Analysis ◽  
Construction Materials ◽  
Unintended Consequences ◽  
Heritage Conservation ◽  
Space Environment ◽  
Historic Buildings ◽  
Building Stock ◽  
Conservation Area

With buildings being responsible for nearly a quarter of global greenhouse gas emissions, intensive building decarbonization programs are in place worldwide, with unintended consequences for historic buildings. To this end, national and international guidance on energy efficiency for historic buildings advocate for the adoption of a ‘whole house approach’ that integrates heritage values in energy efficiency plans. Most guidance, though, relies on non-evidence based, pre-assumptions of residents’ heritage values. And yet, unless we understand how and why residents negotiate their decisions between energy efficiency, thermal comfort, and heritage conservation, such guidance will not be applicable. Despite the urgency to decarbonize the building stock, research on how inhabitants of old buildings make such decisions is extremely limited. It is also case-study specific, often lacking the required depth. To address this gap, this paper offers the first international, in-depth study on the topic. It does so through a rigorous double-coded, thematic analysis of 59 in-depth semi-structured interviews (totaling 206,771 words) carried out in Greece, Mexico, and the UK. The thematic analysis is combined with system dynamic analysis, essential for unveiling what parameters affect inhabitants’ decisions over time. Drawing on theories on the dynamics of social practices, we conclude that the process of decision-making on energy efficiency, thermal comfort improvement, and heritage conservation is a socio-cultural, dynamic practice, the change and continuation of which depends on how the following elements are connected or disconnected: materials (e.g., original features), competencies (e.g., restoration skills), resources (e.g., costs), values, space/environment (e.g., natural light), senses (e.g., thermal comfort), and time (e.g., years living in the house). The connection or disconnection of those elements will depend on (a) the nature of the context (e.g., rural, urban, conservation area); (b) the listing status; (c) age and construction materials of building; (d) local climate; and (e) ownership status.

scholarly journals Normal background levels of air and surface mould reserve in UK residential building stock

2019 ◽  
Author(s):  
Yasemin Didem Aktas ◽  
Morten Reeslev ◽  
Hector Altamirano ◽  
Neil May ◽  
Dina D'Ayala
Keyword(s):  
Indoor Environment ◽  
Residential Building ◽  
Surface Cleaning ◽  
National Standards ◽  
Mould Growth ◽  
Building Stock ◽  
Local Climate ◽  
Background Levels ◽  
Water Damage ◽  
Indoor Mould

This paper reports results obtained from a surface (both visually clean and dirty/dusty surfaces) and active (aggressive) air testing scheme on 140 residential rooms in England, without visible water damage or mould growth, along with a few rooms with visible mould growth/water damage tested for comparison purposes, with the aim of providing background levels of mould in non-water-damaged interiors to benchmark a normal indoor environment, and in turn when there is a need for further investigation, and, possibly, remediation. Air and surface mould was quantified based on the activity of β-N-acetylhexosaminidase (EC 3.2.1.52; NAHA). The obtained readings showed a log-normal distribution. 98% of the samples obtained from visually clean surfaces were equal to or less than 25 relative fluorescence units (RFU), which is suggested to be the higher bound for the range which can be used as a success criterion for surface cleaning/remediation in non-problem buildings. Of samples obtained from visually dirty/dusty surfaces, around 98% were below 450 RFU, which is suggested to define the lower-bound for abnormally high levels of mould, rare even on dirty/dusty surfaces. Similarly, around 98% of the air samples were found to have 1700 RFU or below. Values above 1700 RFU are therefore unlikely in a non-problem indoor environment and can be indicative of a possible problem inducing mould growth. The samples with values below 1700 were further divided into three proposed sub-categories. Finally, these values were compared to those obtained in Denmark in a similar study and are currently used in national standards, and they were found highly congruent, suggesting that local climate regimes and room functions might not be as influential on indoor mould levels, or that the nuances between UK and Denmark in terms of these factors are not strong enough to lead to sizable changes in the typical indoor mould levels in these countries.

scholarly journals Assessment of interstitial mould growth through impaction: a feasibility study

2020 ◽  
Vol 172 ◽  
pp. 20009
Author(s):  
Spyridon Efthymiopoulos ◽  
Hector Altamirano ◽  
Valentina Marincioni
Keyword(s):  
Energy Consumption ◽  
Statistical Analysis ◽  
Thermal Property ◽  
Feasibility Study ◽  
Strong Correlation ◽  
Real Life ◽  
Unintended Consequences ◽  
Small Scale ◽  
Mould Growth ◽  
Solid Walls

The application of insulation to solid walls is one of the measures to help reduce the energy consumption of a building. Where external wall insulation is not feasible (e.g. listed buildings), internal insulation may be the only option to improve the thermal property of external walls. However, such interventions may be followed by unintended consequences [1], such as moisture accumulation and the growth of mould [2]. The study aims to develop a method for the non-disruptive assessment of interstitial mould growth in internally insulated walls. Air sampling through impaction and culture-based analysis was used in the study. Mould species commonly found in buildings were cultivated and used in small-scale experiments, and the effects of several sampling periods and airflow rates assessed. Potential relationships between the sampling variables and the results were determined by means of statistical analysis - a strong correlation between the coverage of mould behind the wall and the sampling periods and airflow rates. The effect of the inertial impaction frequency on the sampling results and the feasibility and applicability of the suggested methodology in real-life scenarios are also discussed.

scholarly journals Normal background levels of air and surface mould reserve in English residential building stock: a preliminary study towards benchmarks based on NAHA measurements

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Yasemin Didem Aktas ◽  
Morten Reeslev ◽  
Héctor Altamirano ◽  
Neil May ◽  
Dina F. D’Ayala
Keyword(s):  
Indoor Environment ◽  
Surface Cleaning ◽  
National Standards ◽  
Mould Growth ◽  
Building Stock ◽  
Local Climate ◽  
Background Levels ◽  
Water Damage ◽  
Normal Background ◽  
Indoor Mould

This paper reports results obtained from a surface (both visually clean and dirty/dusty surfaces) and active (aggressive or activated) air testing scheme on 140 residential rooms in England, without visible water damage or mould growth, along with a few rooms with visible mould growth/water damage tested for comparison purposes. The aim was to establish normal background levels of mould in non-water-damaged interiors to benchmark a ‘normal’ indoor environment, and in turn when there is a need for further investigation, and, possibly, remediation. Air and surface mould was quantified based on the activity of β-N-acetylhexosaminidase (EC 3.2.1.52; NAHA). The obtained readings showed a log-normal distribution. Ninety-eight percent of the samples obtained from visually clean surfaces were equal to or less than 25 relative fluorescence units (RFU), which is suggested to be the higher bound for the range which can be used as a success criterion for surface cleaning/remediation. Of samples obtained from visually dirty/dusty surfaces, around 98% were below 450 RFU, which is suggested to define the lower-bound for abnormally high levels of mould, rare even on dirty/dusty surfaces. Similarly, around 98% of the air samples were found to have 1700 RFU or below. Values above 1700 RFU are therefore deemed unlikely in a non-problem indoor environment and can be indicative of a possible problem inducing mould growth. The samples with values below 1700 were further divided into three proposed sub-categories. Finally, the obtained RFU values and the suggested benchmarks were compared to those obtained from 17 non-residential indoor environments tested previously in Copenhagen, and the benchmarks that are currently used in Danish national standards, and they were both found to be highly congruent, suggesting that local climate regimes and room functions might not be as influential on indoor mould levels as commonly thought, or that the nuances between England and Denmark in terms of these factors are not strong enough to lead to sizable changes in the typical indoor mould levels in these countries’ building stocks.

scholarly journals Understanding zero deforestation and the High Carbon Stock Approach in a highly forested tropical country

2021 ◽  
Author(s):  
Joss Lyons-White ◽  
Christian Mikolo Yobo ◽  
Robert M. Ewers ◽  
Andrew T. Knight
Keyword(s):  
Land Use ◽  
Palm Oil ◽  
Land Use Planning ◽  
Carbon Stock ◽  
Industrial Development ◽  
Unintended Consequences ◽  
International Standards ◽  
Critical Systems ◽  
High Carbon ◽  
Degraded Land

“Zero deforestation” commitments are pledges by companies to avoid deforestation when producing palm oil. Zero deforestation can be implemented using the High Carbon Stock Approach (HCSA), a tool that distinguishes forests from degraded land which can be developed. In highly forested countries like Gabon, zero deforestation may conflict with national economic goals involving palm oil and other agricultural commodities. We investigated perspectives of stakeholders in Gabon about zero deforestation and the HCSA using Critical Systems Heuristics, a systems thinking methodology. In 25 interviews with government, NGOs, companies, and research institutions, and two focus groups with rural communities, we identified three contrasting perspectives on forest conservation and agro-industrial development: international, national, and local. Zero deforestation represents an international perspective that marginalises issues from a national perspective. This may produce unintended consequences that undermine the legitimacy of zero deforestation, including conversion of Gabon’s savannahs and disincentives for sustainable business development. From a local perspective, zero deforestation is embedded in an agro-industrial vision that marginalises value judgments concerning forests and traditional livelihoods. Gabon’s National Land Use Plan could help reconcile the three perspectives but requires recognition by international standards. Adapting the HCSA should also be considered. Research is required to ensure proposed institutional arrangements deliver equitable multi-stakeholder participation in land-use planning. Gabon’s case shows the applicability of zero deforestation to all highly forested countries cannot be assumed. Improved international understanding of national contexts, and flexibility in applying “zero deforestation”, is important for designing effective and equitable international standards for sustainable agricultural production.

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