Non-expert summaryThis article presents an interdisciplinary roadmap showing the importance of cleaning and decontamination activities across a range of socio-economic sectors and in daily life. It captures the expertise and state-of-the art in terms of the fundamental understanding of the underpinning science behind cleaning and decontamination activities, as well as its practical implementation. The roadmap also highlights shortcomings and critical needs in the field at the scientific and practical levels, with some strategies to address them.
Non-expert summaryThe Report Executive Summary states: "The Trade-off Tool for Sampling (TOTS) is a tool under development that aids planners, responders, and subject matter experts in developing defensible yet practicable sample collection plans following a biological contamination incident. The U.S. Environmental Protection Agency (EPA) held a table-top exercise (TTX) with two separate groups of people. The purpose of the TTX was to gather critical end-user feedback on the utility of the tool for future revisions of TOTS and to increase collective (responders, planners, and researchers) understanding of challenges during the sampling and analysis plan (SAP) development for biological incidents, all for the goal of strengthening EPA’s capabilities in this area. The first TTX session was held at the 2019 EPA International Decontamination Conference in Norfolk, Virginia (November 18, 2019), and the second TTX session was held at the EPA On-scene Coordinator (OSC) Academy in Chicago, Illinois (February 26, 2020). The ultimate goal is to provide EPA planners and operational personnel (e.g., on-scene coordinators) the tools and resources necessary to effectively and efficiently plan and execute EPA’s response obligations."
Non-expert summaryThe executive summary of this US EPA report states: "A large-scale aerosol release of a persistent, disease-causing biological agent can result in contamination of a wide area, and may require significant time and resources for recovery depending on the severity of adverse health effects on the exposed population(s). Many unknowns are associated with characterization and clearance sampling during response to a wide-area (including indoor, outdoor, and underground area) biological incident. The biological agent and its characteristics, the release mechanism, amount of contaminant released, and a plethora of environmental and meteorological factors are completely separate, yet interconnected processes that greatly influence the extent and level of contamination. Similarly, decisions related to the sampling strategy (i.e., sample medium, sampling area, spacing, etc.) will affect the cost, time, amount of waste generated, and personnel (i.e., resource demand) required to characterize and clear the contaminated area. The process of understanding how these elements influence one another and contribute to the overall problem is referred to as a systems approach. To what degree sampling and, more specifically, variations in the sampling strategy interact and contribute to overall resource demand, following a wide area biological incident, is still largely unknown. To date, there have been no attempts to model characterization sampling following a wide-area biological incident."
Non-expert summaryThis book chapter is a review of biofilm dynamics, modelling and simulation. The modeling of biochemical processes in biofilms is more complex compared to those in suspended biomass due to the existence of substrate gradients. The review traces the development of modelling approaches from 1-D mass transfer and removal mechanisms to 2D and 3D descriptions including more levels of physical insight.
Non-expert summaryThis is a review of the fluid mechanics associated with blistering, which occurs when a thin solid layer locally separates from an underlying substrate through cracking of a bulk material, delamination of a composite material, or peeling of a thin layer (membrane) adhered to the substrate by a thin layer of viscous fluid. The focus of the review is on the latter case, where the expansion of the newly formed blister by fluid injection occurs via a displacement flow, which peels the adhered surfaces apart through a two-way interaction between flow and deformation. These blisters are prone to fluid- and solid-mechanical instabilities. If the injected fluid is less viscous than the fluid already occupying the gap, patterns of short and stubby fingers (fingering) form on the propagating fluid interface. Buckling/wrinkling instabilities of the delaminated layer can arise for sufficiently thin membranes and can interact with the fluid mechanical fingering instability.
Non-expert summaryBroad review of the fluid mechanics involved in the cleaning and decontamination of surfaces using liquid flows. Three main phases are reviewed: the contacting phase, which requires the liquid cleanser to reach the soil; the action phase, which studies the various physico-chemical effects of the cleanser on the soil; and the removal phase, where the cleanser transports the soil away from the surface through various phenomena.
Non-expert summaryThis is a short review presenting and comparing five apparatuses that are used in laboratory scale investigations of cleaning: the parallel plate flow cell, the impinging jet, the radial flow cell, the rotating disk and fluid dynamic gauging. These systems are of particular relevance to the study of surface fouling, surface cleaning or adhesion on solid surfaces in laboratory environment. The key features of their hydrodynamics, as well as their practical advantages and drawbacks, are discussed. Examples of applications fields are also listed. A useful introduction to these devices.
Non-expert summaryThis is a review of heat transfer and flow phenomena during unsubmerged liquid jet impingement on solid surfaces, such as when a water jet passes through air and impinges on a wall. Both axisymmetric and planar jets are considered. The focus is on convective transport without phase change. Results for the stagnation zone are given first, followed by those for the regions downstream. Correlations are presented for flow and heat transfer phenomena. The heat fluxes that can be generated in these systems can be large, so there is a considerable body of work on topic. Splattering - the formation of breakaway droplets from the liquid film - that accompanies turbulent jet impingement is described. Other aspects of liquid jet impingement cooling are discussed briefly.
Non-expert summaryThis is a review of social science studies on the social problems of environmental contamination and the social factors that affect cleanup processes and outcomes. It does not focus on technical aspects. An interdisciplinary literature review identified 97 articles and identified three themes: effects on cleanup worker health; public engagement and decision making; and societal benefits of cleaned-up sites. The need to link up various societal factors in making environmental cleanup policy is highlighted.