Evaluation of a Bioaerosol Sampler for Indoor Environmental Surveillance of Severe Acute Respiratory Syndrome Coronavirus 2

The worldwide spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has ubiquitously impacted many aspects of life. As vaccines continue to be manufactured and administered, limiting the spread of SARS-CoV-2 will rely more heavily on the early identification of contagious individuals occupying reopened and increasingly populated indoor environments. In this study, we investigated the utility of an impaction-based aerosol sampling system with multiple nucleic acid collection media. Heat-inactivated SARS-CoV-2 was utilized to perform bench-scale, short-range aerosol, and room-scale aerosol experiments. Through bench-scale experiments, AerosolSense Capture Media (ACM) and nylon flocked swabs were identified as the highest utility media. In room-scale aerosol experiments, consistent detection of aerosol SARS-CoV-2 was achieved at a concentration equal to or greater than 0.089 genome copies per liter of room air (gc/L) when air was sampled for eight hours or more at less than one air change per hour (ACH). Shorter sampling periods (~75 minutes) yielded consistent detection at ~31.8 gc/L of room air and intermittent detection down to ~0.318 gc/L at (1 and 6+ ACH respectively). These results support further exploration in real-world testing scenarios and suggest the utility of indoor aerosol surveillance as an effective risk mitigation strategy in occupied buildings.

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Evaluation of a bioaerosol sampler for indoor environmental surveillance of Severe Acute Respiratory Syndrome Coronavirus 2

PLoS ONE ◽

10.1371/journal.pone.0257689 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0257689

Author(s):

Patrick Finn Horve ◽

Leslie Dietz ◽

Dale Northcutt ◽

Jason Stenson ◽

Kevin Van Den Wymelenberg

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Early Identification ◽

Short Range ◽

Risk Mitigation ◽

Mitigation Strategy ◽

Indoor Environments ◽

Environmental Surveillance ◽

Sampling System ◽

Bench Scale ◽

Indoor Aerosol

The worldwide spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has ubiquitously impacted many aspects of life. As vaccines continue to be manufactured and administered, limiting the spread of SARS-CoV-2 will rely more heavily on the early identification of contagious individuals occupying reopened and increasingly populated indoor environments. In this study, we investigated the utility of an impaction-based bioaerosol sampling system with multiple nucleic acid collection media. Heat-inactivated SARS-CoV-2 was utilized to perform bench-scale, short-range aerosol, and room-scale aerosol experiments. Through bench-scale experiments, AerosolSense Capture Media (ACM) and nylon flocked swabs were identified as the highest utility media. In room-scale aerosol experiments, consistent detection of aerosol SARS-CoV-2 was achieved at an estimated aerosol concentration equal to or greater than 0.089 genome copies per liter of room air (gc/L) when air was sampled for eight hours or more at less than one air change per hour (ACH). Shorter sampling periods (75 minutes) yielded consistent detection at ~31.8 gc/L of room air and intermittent detection down to ~0.318 gc/L at (at both 1 and 6 ACH). These results support further exploration in real-world testing scenarios and suggest the utility of indoor aerosol surveillance as an effective risk mitigation strategy in occupied buildings.

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Selection of risk mitigation strategy in electronic supply chains using grey theory and digraph-matrix approaches

International Journal of Production Research ◽

10.1080/00207543.2014.948579 ◽

2014 ◽

Vol 53 (1) ◽

pp. 238-257 ◽

Cited By ~ 54

Author(s):

R. Rajesh ◽

V. Ravi ◽

R. Venkata Rao

Keyword(s):

Supply Chains ◽

Risk Mitigation ◽

Mitigation Strategy ◽

Grey Theory ◽

Selection Of

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Aerosol sampling and Transport Efficiency Calculation (ASTEC) and application to surtsey/DCH aerosol sampling system: Code version 1. 0: Code description and user's manual

10.2172/6065981 ◽

1989 ◽

Author(s):

N. Yamano ◽

J. E. Brockmann

Keyword(s):

Aerosol Sampling ◽

Sampling System ◽

Transport Efficiency ◽

Efficiency Calculation ◽

Code Version

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Coordinated Risk Mitigation Strategy For Integrated Energy Systems Under Cyber-Attacks

IEEE Transactions on Power Systems ◽

10.1109/tpwrs.2020.2986455 ◽

2020 ◽

Vol 35 (5) ◽

pp. 4014-4025 ◽

Cited By ~ 1

Author(s):

Pengfei Zhao ◽

Chenghong Gu ◽

Da Huo

Keyword(s):

Risk Mitigation ◽

Energy Systems ◽

Mitigation Strategy ◽

Cyber Attacks ◽

Integrated Energy Systems

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Behavior of Listeria innocua during the manufacturing and pit-ripening of Formaggio di Fossa di Sogliano PDO cheese

Italian Journal of Food Safety ◽

10.4081/ijfs.2020.8552 ◽

2020 ◽

Vol 9 (2) ◽

Author(s):

Federica Giacometti ◽

Paolo Daminelli ◽

Laura Fiorentini ◽

Elena Cosciani-Cunico ◽

Paola Monastero ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Risk Mitigation ◽

Scientific Evidence ◽

Challenge Test ◽

Mitigation Strategy ◽

Listeria Innocua ◽

Ripening Process ◽

Protected Designation Of Origin ◽

The Impact

Formaggio di Fossa di Sogliano is a traditional Italian Protected Designation of Origin (PDO) cheese ripened for a minimum of 5 months, with the feature of a ripening of at least 80 to at most 100 days in pits, digged into tuffaceous rocks according to medieval tradition of Italy. In this study, a challenge test using Listeria innocua as a surrogate of Listeria monocytogenes was performed, with the aim of increasing knowledge concerning the impact of the Fossa cheese process, and especially of the traditional ripening process of this PDO, on the behaviour of L. monocytogenes. Pasteurized milk was experimentally inoculated with 4.5 log CFU/mL cocktail by three L. innocua strains, and L. innocua and Mesophilic Lactic Acid Bacteria (LAB) counts as well as the evolution of temperatures, pH and aw values were monitored throughout the manufacturing and ripening processes. Throughout the ripening in maturation room a constant temperature of 8°C was observed reaching a temperature between 10 and 15.5°C during ripening into pit. In the final products data for LAB concentration, pH and aw values were roughly in accordance with literature, even if some differences were, probably due to variability of artisanal cheese productions. The numbers of L. innocua showed a slight decrease but remained stable until the end of ripening in maturation room, whereas a significant reduction of the microorganism was observed in the final product, at the end of the ripening into the pit. The findings give scientific evidence that the process of this PDO prevented the L. innocua growth, allowing us to speculate a similar behaviour of L. monocytogenes. Based on this study, the recommendation to extend as much as possible the ripening into pit (from 80 to 100 days) was provided to food business operators as a risk mitigation strategy to be implemented.

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Arc flash: a risk assessment and mitigation strategy

The APPEA Journal ◽

10.1071/aj10117 ◽

2011 ◽

Vol 51 (2) ◽

pp. 737

Author(s):

Danny Norton ◽

Dale Wright

Keyword(s):

Risk Assessment ◽

Oil And Gas ◽

Capital Expenditure ◽

Risk Mitigation ◽

Cumulative Effect ◽

Mitigation Strategy ◽

Assessment Process ◽

Mitigation Measures ◽

Safe Work ◽

Arc Flash

Oil and gas facility managers are well aware that attention to detail saves lives and supports business continuity and reputation. Those tasked with stewardship of electrical assets will be aware of the need to protect their employees from the hazard of electrical arc flash and that it should be at the forefront of safety thinking. Complacency and lack of duty of care with this real and possibly un-quantified hazard can lead to fatalities. The primary solution to arc flash consequences in older installations has been the implementation of safe work procedures and personal protective equipment. While still valid, these solutions are the least effective options in the hierarchy of controls. SKM have developed a practical risk mitigation strategy that considers the hazards of prospective arc flash energy together with the cumulative effect of switchboard age, design, capability and condition. The strategy also considers the range of potential mitigation controls available through the mechanism of substitution and engineering design that focuses on reducing: The likelihood of an arc flash incident occurring; The likelihood of personnel exposure; and, The energy released should an incident occur. A structured arc flash risk assessment process can provide the asset owner the opportunity to rank individual switchboards for likelihood, consequence and risk, and thus provide direction for engineered remediation and capital expenditure. SKM proposes the way in which arc flash risk can be assessed, how appropriate layered mitigation measures might be selected, and how an asset owner may approach the issue of arc flash hazard mitigation to economically and reliably protect its employees.

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Precision of an Ambient Sequential Acid Aerosol Sampling System

Applied Occupational and Environmental Hygiene ◽

10.1080/1047322x.1993.10389212 ◽

1993 ◽

Vol 8 (4) ◽

pp. 313-316 ◽

Cited By ~ 2

Author(s):

Peter A. Jaques ◽

George D. Thurston ◽

Patrick L. Kinney ◽

John E. Gorczynski

Keyword(s):

Aerosol Sampling ◽

Sampling System

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Nanoparticle Behaviour in an Urban Street Canyon at Different Heights and Implications on Indoor Respiratory Doses

Atmosphere ◽

10.3390/atmos10120772 ◽

2019 ◽

Vol 10 (12) ◽

pp. 772 ◽

Cited By ~ 2

Author(s):

Manigrasso ◽

Protano ◽

Vitali ◽

Avino

Keyword(s):

Street Canyon ◽

Ultrafine Particles ◽

Ground Level ◽

Daily Basis ◽

Total Daily Dose ◽

Indoor Environments ◽

Size Distributions ◽

Ground Floor ◽

Urban Street ◽

Indoor Aerosol

The amount of outdoor particles that indoor environments receive depends on the particle infiltration factors (Fin), peculiar of each environment, and on the outdoor aerosol concentrations and size distributions. The respiratory doses received, while residing indoor, will change accordingly. This study aims to ascertain to what extent such doses are affected by the vertical distance from the traffic sources. Particle number size distributions have been simultaneously measured at street level and at about 20 m height in a street canyon in downtown Rome. The same Fin have been adopted to estimate indoor aerosol concentrations, due to the infiltration of outdoor particles and then the relevant daily respiratory doses. Aerosol concentrations at ground floor were more than double than at 20 m height and richer in ultrafine particles. Thus, although aerosol infiltration efficiency was on average higher at 20 m height than at ground floor, particles more abundantly infiltrated at ground level. On a daily basis, this involved a 2.5-fold higher dose at ground level than at 20 m height. At both levels, such doses were greater than those estimated over the period of activity of some indoor aerosol sources; therefore, they represent an important contribution to the total daily dose.

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