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Biocontaminants represent higher risks to occupants' health in shared spaces. Natural ventilation is an effective strategy against indoor air biocontamination. However, the relationship between natural ventilation and indoor air contamination requires an in-depth investigation of the behavior of airborne infectious diseases, particularly concerning the contaminant's viral and aerodynamic characteristics. This research investigates the effectiveness of natural ventilation in preventing infection risks for coronavirus disease (COVID-19) through indoor air contamination of a free-running, naturally-ventilated room (where no space conditioning is used) that contains a person having COVID-19 through building-related parameters.

This research adopts a case study strategy involving a simulation-based approach. A simulation pipeline is implemented through a number of design scenarios for an open office. The simulation pipeline performs integrated contamination analysis, coupling a parametric 3D design environment, computational fluid dynamics (CFD) and energy simulations. The results of the implemented pipeline for COVID-19 are evaluated for building and environment-related parameters. Study metrics are identified as indoor air contamination levels, discharge period and the time of infection.

According to the simulation results, higher indoor air temperatures help to reduce the infection risk. Free-running spring and fall seasons can pose higher infection risk as compared to summer. Higher opening-to-wall ratios have higher potential to reduce infection risk. Adjacent window configuration has an advantage over opposite window configuration. As a design strategy, increasing opening-to-wall ratio has a higher impact on reducing the infection risk as compared to changing the opening configuration from opposite to adjacent. However, each building setup is a unique case that requires a systematic investigation to reliably understand the complex airflow and contaminant dispersion behavior. Metrics, strategies and actions to minimize indoor contamination risks should be addressed in future building standards. The simulation pipeline developed in this study has the potential to support decision-making during the adaptation of existing buildings to pandemic conditions and the design of new buildings.

The addressed need of investigation is especially crucial for the COVID-19 that is contagious and hazardous in shared indoors due to its aerodynamic behavior, faster transmission rates and high viral replicability. This research contributes to the current literature by presenting the simulation-based results for COVID-19 as investigated through building-related and environment-related parameters against contaminant concentration levels, the discharge period and the time of infection. Accordingly, this research presents results to provide a basis for a broader understanding of the correlation between the built environment and the aerodynamic behavior of COVID-19.

Hazardous and radioactive wastes are routinely disposed of in shallow land disposal facilities at sites that have undergone environmental remediation. These residual contaminants, which remain on-site in these isolation facilities, continue to pose risks to humans and the environment and represent extremely long-term liabilities that require continuous management.

This paper draws upon the experiences generated from two federal programs established in response to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978 and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980. Operational issues arising at existing sites suggest that there is a need to better integrate the management functions at contaminant isolation facilities. To protect human health and safeguard the natural environment, more sustainable environmental protection systems are required for the long-term management of residual contaminants. A series of logic diagrams are introduced to improve the integration and management of remedial processes, engineered barriers and institutional controls. These institutional responsibilities need to be monitored and maintained by the appropriate site stewards to ensure continued system performance.

Outlines research work [by the Machine Vision Group at Royal Holloway] into an x‐ray inspection system able to detect contaminants in packaged food products. Describes the analysis of a four‐stage machine vision structure that includes image formation, pre‐processing, feature extraction and decision. The system was tested on various food products and contaminants with the resultant conclusions that the contamination detection system was adaptive and worked with many types of products and contaminants. Refinements in the final decision making stage are being implemented by the use of expert [neural] networks.

The purpose of this paper is to evaluate the results of inspections carried out by the State Veterinary Administration (SVA) of Czech Republic (CR) for the occurrence of chemical contaminants in animal products before and after CR entered the European Union (EU).

Data was collected from e-databases of the SVA from 1999–2016 and sorted into categories (game animals and fish; livestock; food and raw material of animal origin) and time periods (one before entry and two after entry of CR to the EU). Analyses of the samples were categorized as “positive samples” (any presence of contaminants) and “samples above the MRL” (presence of contaminants exceeding the maximum residue levels).

Results showed a significant decrease in the number of positive findings of contaminants during the monitored years 1999–2016, especially after CR entered the EU. Most encouragingly, the number of samples that exceeded the MRL was less than 1 percent from all the tested samples of animal origin and, after entry to the EU, in one category (food and raw materials of animal origin) it was even less than 0.1 percent. Findings of banned substances indicate continued environmental contamination in CR; however, this remains a problem in most of Europe due to their extensive use in the past and slow degradation.

This paper provides an overview of the occurrence of chemical contaminants and their levels in food of animal origin in view of the changing legislative requirements before and after CR entered the EU.

Studies are made on food three‐layer packages, where a contaminated recycled polymer layer is located between two virgin polymer layers. As the thick food packages are made by pressing the polymer layers in a mould kept at around the melting temperature of the polymer, the process is thus rather complex with heat transfer and contaminant transfer. Heat transfer is controlled by conduction through the package with a high coefficient of heat transfer in the mould, and conduction through the package and free convection at the surface during the cooling period in motionless air. The contaminant transfer is controlled by diffusion through the polymer with a temperature‐dependent diffusivity. A numerical model taking into account both the heat and mass transfer is built in order to resolve the problem. Various parameters appear of interest, such as the conditions of the processing with the temperature of the mould and time in the mould, the thicknesses of the polymer layers. Two types of sandwich are considered with different thicknesses for each layer. The profiles of concentration of the contaminant are obtained through the polymer packages.

This paper presents the results of laboratory experiments that investigate the removal of volatile organic compounds from saturated soils through the use of air sparging. Three series of experiments were performed in a column test apparatus using two different soils to represent actual field conditions, namely, a fine gravel and a medium‐to‐fine Ottawa sand (both obtained from sources near Chicago, Illinois, USA) contaminated with toluene, a major constituent of petroleum products. The results showed that toluene was removed from gravel very efficiently using air sparging; complete removal was achieved using a variety of air flow rates. However the toluene removal rates in tests using sand were significantly less. Even at the highest air flow rate used during testing, complete toluene removal took eight times longer than in comparable tests using gravel. With low air flow rates this was not achieved even after 17 hours of testing. It was further found that the injection of foams generated with surfactants, SDS and witconol SN70, at low air flow rates during the use of air sparging was found to accelerate the bulk removal of toluene in sand, but the use of surfactants did not facilitate the removal of residual levels of contamination.

The increasing demand for organic foods is explained mainly by consumers' concerns about the quality and safety of foods and their perception that organically produced foods are healthier and safer than conventional foods. Based on internationally available concentration data of organic and conventional vegetables (carrots, tomatoes, lettuce and spinach) and potatoes, the paper aims to investigate the scientific validity of nutrition claims as “no vegetable/potato has higher amounts of nutrient X than organic vegetables/potatoes” and “no vegetable/potato has lower amounts of contaminant Y than organic vegetables/potatoes”.

Detailed nutrient and contaminant databases were developed for organic and conventional vegetables separately. Non‐parametric (Mann‐Whitney test) methods were used to detect significant differences between both types of vegetables. A chi‐square test was used to compare the incidence of pesticide residues in organic and conventional vegetables.

From a nutritional and toxicological point of view, organic vegetables and potato in general are not significantly better than conventional vegetables and potatoes. For some nutrients and contaminants organic vegetables and potatoes score significantly better but for others they score significantly worse. Therefore, it becomes difficult to justify general claims indicating a surplus value of organic over conventional vegetables and potatoes. More data from controlled paired studies are needed to reconsider the use of claims for these organic plant foods in the future.

Only a limited number of studies comparing the nutrient and/or contaminant concentration of organic and conventional vegetables are available (“paired studies”). Additionally, the majority of the studies are of moderate or poor quality. The implication is that more of those paired studies are heavily needed. Another limitation of the study is the fact that most pesticide residue data originated from the USA, the EU and Australia.

So far only few studies compared both nutrient and contaminant contents between organic and conventional plant foods. This paper covers therefore an important, not well‐explored research sub area.

A comprehensive investigation on the outlet air position effects on the thermal comfort and air quality has been achieved. In addition, airflow and temperature distributions in ventilated cavities filled with an air-CO₂ mixture with mixed convection are predicted. The airflow enters from the cavity through an opening in the lower side of the left vertical wall and exits through the opening in one wall of the cavity. This paper aims to investigate the outlet location effect, four different placement configurations of output ports are considered. Three of them are placed on the upper side and the fourth on top of the opposite side of the inlet opening. A uniform heat and CO₂ contaminant source are applied on the left vertical wall, while the remaining walls are impermeable and adiabatic to heat and solute. The cooling efficiency inside the enclosure and the average fluid temperature are computed for different Reynolds and Rayleigh numbers to find the most suitable fluid outlet position that ensures indoor comfortable conditions while effectively removing heat and the contaminant. This is demonstrated by three relevant indices, namely, the effectiveness for heat removal, the contaminant removal and the index of indoor air quality.

The simulations were performed via the finite-volume scSTREAM CFD solver V11. Three different values of CO₂ amount are considered, namely, 10³, 2 × 10³ and 3 × 10³ ppm, the Reynolds number being in the range 100 ≤ Re ≤ 800.

Based on the findings obtained, it is the configuration whose air outlet is placed near the heat source and the contaminant, which provides a better air distribution and a ventilation efficiency compared to the others ventilation strategies.

The studies on heat and mass transfers by natural and forced convection in ventilated cavities remain a fruitful research topic. Thereby, such a study deals with different ventilation strategies through cavities containing an air-CO₂ mixture subjected to a mixed regime. In particular, the air inlet velocity and contaminant sources’ effects on thermal comfort and air quality have been investigated.

The purpose of this paper is to develop new knowledge in experimental characterization of contaminants in engine lubricants, using surface plasmon resonance (SPR) sensing that can be applicable for on‐line condition monitoring of lubricant quality and engine component performance.

The effect of change in optical properties (e.g. transparency, absorption, and refractive index) of engine lubricants caused by the introduction of contaminants, such as gasoline, coolant, and water, on the surface plasmon resonance characteristics is analyzed experimentally. In SPR measurement, variations in both the refractive index and absorption cause changes in the SPR curve, which is the dependence of reflectivity vs incidence angle. The SPR characteristics (e.g. refractivity) of engine lubricant contaminated by gasoline, water and coolant at different concentration are measured as a function of resonance angle and analyzed with respect to different concentration (1%‐10%) of contaminants. Also, pattern recognition analysis between fresh and used engine lubricants is performed, to show applicability of Bayesian classification methodology for on‐line monitoring and predicting engine lubricant condition.

It was shown experimentally that attenuation of surface plasmons due to introduction of contaminants to the engine lubricant leads to a noticeable change in resonance angle and reflectivity minimum of the SPR curve due to an increase in the dielectric permittivity. In addition, the changes in the SPR characteristics were observed between fresh and used engine lubricant, causing resonance angle and reflectivity minimum of the SPR curve to shift.

The knowledge generated in this study lays the informational basis to further develop an on‐line system for engine lubricant condition monitoring using miniaturized SPR sensors fully suitable for on board applications.

SPR characterization is originally applied for analysis of optical properties of engine lubricants caused by the introduction of contaminants, such as gasoline, coolant, and water.

Exposure to poor indoor air in refurbished buildings is a matter of health concern due to the growing concentrations of various contaminants as a result of building airtightness without amendment of ventilation, or the use of building materials such as glue, paint, thinner and varnishes. Recent studies have been conducted to measure indoor air pollutants and assess the health risks affecting the quality of life, productivity and well-being of human beings. However, limited review studies have been recently conducted to provide an overview of the state of knowledge. This study aims to conduct a scoping review of indoor air quality (IAQ) in the context of refurbished or energy-retrofitted buildings.

A systematic screening process based on the PRISMA protocol was followed to extract relevant articles. Web of Science, Scopus, Google Scholar and PubMed were searched using customised search formulas. Among 276 potentially relevant records, 38 studies were included in the final review covering a period from 2015 to 2022.

Researchers mapped out the measured compounds in the selected studies and found that carbon dioxide (CO₂) (11%) and total volatile organic compounds (11%) were among the most commonly measured contaminants. Two trends of research were found including (1) the impact of ventilative properties on IAQ and (2) the impact of introducing building materials on IAQ.

The contribution of this study lies in summarising evidence on IAQ measurements in refurbished buildings, discussing recent advancements, revealing significant gaps and limitations, identifying the trends of research and drawing conclusions regarding future research directions on the topic.