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

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

Preface on “Natural hazards' impact on natural and built heritage and infrastructure in urban and rural zones”

This is an overview of the papers published in the special issue.</p

Assessment of heritage timber structures: Review of standards, guidelines and procedures

This paper reviews the official documentation (standards, guidelines and procedures) available for the assessment of heritage timber structures. The subsequent discussion does not catalogue all relevant technical literature. Instead, it intends to convey the state of background knowledge, recommendations and code rules using some illustrative examples. A specific focus is given to visual inspection as a fundamental first step for all different scopes and levels of assessment. The objectives of this review are to: (1) highlight the gaps and limitations in the currently available tools as well as the need for standardization; (2) contribute to the definition of an ontological approach, relating the scope of the assessment, information required and necessary procedures, (3) identify guidance for the different scopes of the assessment. The variety of timber species, architectural typologies and structural solutions, together with the varied response of these structures to climatic and other natural and man-made hazards, warrant a multifaceted and integrated assessment methodology that accounts for the hierarchical nature of timber structures behaviour and the multitude of agents affecting such behaviour. A review of existing standards and guidelines illustrates the need for a tool to consistently record the assessment process and the final decision taken, which will serve to constitute the knowledge base for the development of the next generation of more integrated and heritage specific guidelines

LOG-IDEAH:ASP for architectonic asset preservation

To preserve our cultural heritage, it is important to preserve our architectonic assets, comprising buildings, their decorations and the spaces they encompass. In some geographical areas, occasional natural disasters, specifically earthquakes, damage these cultural assets. Perpetuate is a European Union funded project aimed at establishing a methodology for the classification of the damage to these buildings, expressed as "collapse mechanisms". Structural engineering research has identified 17 different collapse mechanisms for masonry buildings damaged by earthquakes. Following established structural engineering practice, paper-based decisions trees have been specified to encode the recognition process for each of the various collapse mechanisms. In this paper, we report on how answer set programming has been applied to the construction of a machineprocessable representation of these collapse mechanisms as an alternative for these decision-trees and their subsequent verification and application to building records from L'Aquila, Algiers and Rhodes. As a result, we advocate that structural engineers do not require the time-consuming and error-prone method of decisions trees, but can instead specify the properties of collapse mechanisms directly as an answer set program. © Viviana Novelli, Marina De Vos, Julian Padget, and Dina D'Ayala

ASP for architectonic asset preservation

To preserve our cultural heritage, it is important to preserve our architectonic assets, comprising buildings, their decorations and the spaces they encompass. In some geographical areas, occasional natural disasters, specifically earthquakes, damage these cultural assets. Perpetuate is a European Union funded project aimed at establishing a methodology for the classification of the damage to these buildings, expressed as "collapse mechanisms". Structural engineering research has identified 17 different collapse mechanisms for masonry buildings damaged by earthquakes. Following established structural engineering practice, paper-based decisions trees have been specified to encode the recognition process for each of the various collapse mechanisms. In this paper, we report on how answer set programming has been applied to the construction of a machine-processable representation of these collapse mechanisms as an alternative for these decision-trees and their subsequent verification and application to building records from L'Aquila, Algiers and Rhodes. As a result, we advocate that structural engineers do not require the time-consuming and error-prone method of decisions trees, but can instead specify the properties of collapse mechanisms directly as an answer set program

Surface and passive/active air mould sampling: A testing exercise in a North London housing estate

Despite indoor mould being one of the most common problems in residential properties in the UK, there are not any widely accepted methodologies for its measurement. This paper focusses on this problem of measurement and reports on the findings from a rigorous testing scheme carried out to quantify air and surface mould concentrations and particle counts within 71 rooms from 64 properties in North London, some with and some without visible mould. The aim was to investigate the potential of passive and active air sampling strategies (sampling from still and actively mixed air, respectively) to explain visible mould, and understand how home/room characteristics correlate with the obtained readings. Airborne mould levels were quantified using an Andersen sampler (passively and actively), as well as by a chemical method based on the quantification of the N-acetylhexosaminidase (NAHA) activity (actively), which was also used to quantify surface mould. The mould levels were then correlated against physical characteristics of the tested homes/rooms, collected by means of survey sheets developed as part of this study. The findings did not reveal any independent variable governing all or most of the response variables, but a complex analysis suggested that whether it is a house or a flat could depict mould levels in the air and on the surfaces. It was also shown that a robust testing protocol should combine air and surface based methods, and an active air sampling strategy leads to a more accurate appraisal of airborne mould levels. Finally, the results showed that while there is some correlation between visible mould (and other moisture induced problems such as condensation) and measured air mould concentrations, lack of visible mould within a room does not necessarily mean low air mould concentrations, and thus one should not rely solely on visual inspection

GEOMATICS AND CIVIL ENGINEERING INNOVATIVE RESEARCH ON HERITAGE: INTRODUCING THE “ENGINEER” PROJECT

This paper aims to introduce the concept and objectives of a recently supported European project entitled “Geomatics and Civil Engineering Innovative Research on Heritage”, in short ENGINEER. The ENGINEER project visions to enhance and extend inter-departmental multidisciplinary research activities of the Department of Civil Engineering & Geomatics of the Cyprus University of Technology through coordination and support actions as well as through targeted research activities with the support of European leading institutions. Project tasks aim to fill research multidisciplinary gaps, push, and extend knowledge into new and innovative fields dealing with the monitoring, digitization, visualization, and preservation of ancient monuments and cultural heritage sites, assisting their protection, promotion, and safeguarding

Seismic Vulnerability Assessment of Priority Cultural Heritage Structures in the Philippines

At the end of 2013 two catastrophic events occurred in the Philippines: the M 7.2 earthquake in Bohol and the strongest ever recorded Typhoon Haiyan, causing destruction across the islands of Cebu, Bohol and the Visayas region. These events raised the need to carry out a multi-hazard risk assessment of heritage buildings, many of which were irretrievably lost in the disasters. Philippines’ Department of Tourism engaged ARS Progetti S.P.A., Rome, Italy, and the Center for Conservation of Cultural Property and Environment in the Tropics (CCCPET), University of Sto. Tomas, Manila, to undertake the “Assessment of the Multi-Hazard Vulnerability of Priority Cultural Heritage Structures in the Philippines”, with experts from University College London, UK, and De La Salle University. The main objective of the project was to reduce the vulnerability of cultural heritage structures to multiple natural hazards, including earthquake, typhoon, flood, by: (i) prioritizing of specific structures based on hazard maps and historical records; (ii) assessing their vulnerability; and (iii) recommending options to mitigate the impacts on them. The paper presents the methodology introduced to determine the seismic risk these heritage buildings are exposed to. All the selected cultural heritage structures are under the jurisdiction of the National Museum Commission of Philippines and of the National Commission for Culture and Arts

Keynote Lecture – The Interplay of Multiple Hazards and Urban Development: The context of Istanbul

Tomorrow’s Cities is the UK Research and Innovation (UKRI) Global Challenges Research Fund (GCRF) Urban Disaster Risk Hub – an interdisciplinary research hub with the aim to catalyse a transition from crisis management to multi-hazard risk-informed and inclusive planning in four cities in low-and-middle income countries. Istanbul in Turkey is one of the four cities investigated. It is one of the largest urban agglomerations in Europe where more than 15 million people reside in more than 1 million buildings. Considering that the population was 4.75 million in 1980, Istanbul’s urban sprawl was inevitable. Due to an imbalance between the population growth and housing supply, Istanbul’s urbanization was shaped by illegal construction processes producing the gecekondus in almost every part of the city (Gencer and Mentese, 2016). Unplanned urban expansion was so rapid that the urban master plan of 1980, which set the limits and strategies for urban development, became completely invalid by 1989 (Tapan, 1998). This situation led to the development of a new urban master plan in 1994 that included geoscientific analysis, and which highlighted the possibility of losses due to an earthquake on the segments of the North Anatolian Fault in the Marmara Sea. Uncontrolled and unplanned development continued in Istanbul until 1999 when two major earthquakes hit the region causing at least 18.000 deaths and $16 billion economic loss. These events changed the authorities’ perspective to earthquake risk and its mitigation. As a result, the 1998 earthquake resistant design code (published one year before the 1999 earthquakes) was widely embraced and implemented. Furthermore, several urban transformation projects have taken place in the last 20 years for reducing disaster risk. These have had varied success, with research to date showing that areas selected for urban transformation were often chosen on the basis of land value rather than hazard risk, and that a pro-poor approach is missing. Despite these efforts, Istanbul’s earthquake risk remains high. Furthermore, recent urban development plans are seeing the city expand into undeveloped lands to the west, increasing exposure to new hazards, namely flash flooding and landslides. The combined impact of these hazards is not evenly distributed, and the associated risks are heightened by poor infrastructural resilience and social vulnerabilities. Therefore, it is crucial to integrate different types of hazards and risks into the urban development context for future scenarios, so that a physically and socio-economically safer development that prioritizes the wellbeing of local communities can be facilitated. This presentation summarises the research conducted in Istanbul over the first 18 months of the Tomorrow’s Cities Project by a consortium of Turkish and UK researchers. This research spans the better characterisation of earthquake and landslide hazards, development of analysis methods for predicting the response of case study buildings to multiple hazards and a Bayesian network based approach for assessing road infrastructure resilience under multiple hazard scenarios. Furthermore, plans for building a Resilient Urban Development Decision Support Environment (RUD-DSE) for communicating the relevance of this research on future urban planning is described