A comparison of the World Health Organisation's HEAT model results using a non-linear physical activity dose response function with results from the existing tool

IntroductionThe WHO-Europe’s Health Economic Assessment Tool is a tool used to estimatethe costs and benefits of changes in walking and cycling. Due to data limitationsthe tool’s physical activity module assumes a linear dose response relationship be-tween physical activity and mortality.MethodsThis study estimates baseline population physical activity distributions for 44 coun-tries included in the HEAT. It then compares, for three different scenarios, the re-sults generated by the current method, using a linear dose-response relationship,with results generated using a non-linear dose-response relationship.ResultsThe study finds that estimated deaths averted are relatively higher (lower) using thenon-linear effect in countries with less (more) active populations. This difference islargest for interventions which affect the activity levels of the least active the most.Since more active populations, e.g. in Eastern Europe, also tend to have lowerValue of a Statistical Life estimates the net monetary benefit estimated by the sce-narios are much higher in western-Europe than eastern-Europe.ConclusionsUsing a non-linear dose response function results in materially different estimateswhere populations are particularly inactive or particularly active. Estimating base-line distributions is possible with limited additional data requirements, although themethod has yet to be validated. Given the significant role of the physical activitymodule within the HEAT tool it is likely that in the evaluation of many interventionsthe monetary benefit estimates will be sensitive to the choice of the physical activitydose response function.

Corrosion risk assessment for sheet piles in road environment – using ISO9223 dose response function and long term exposure samples

<p>Road side environments exposed to de-icing salts do not readily fall within any of the qualitative assessment categories commonly used in ISO 9223 to define corrosion risk. The potential impact of seasonal use of de-icing salts complicates the definition of the environment and may increase corrosion rates. It is therefore common within highways authorities to assume the environment is comparable to a marine splash zone, C5 environment of ISO 9223, equating to a high corrosion loss for 120-year design life. In the absence of data this may be an understandable, if conservative, assumption. This paper challenges this assumption and presents a detailed case study for sheet piling adjacent to highways, exploring the benefits of a quantitative assessment using the Dose Response Function methodology given in ISO 9223 and calculation of long-term loss in accordance with ISO 9224. The method allows better definition of the service environment and results in more modest assessment of total corrosion loss. The assessed corrosion loss from this methodology is compared with the results obtained from the recovery and analysis of long-term exposure samples from the English trunk road network. The range of total corrosion loss of the mild steel samples recovered, fall within the range predicted by the analysis using the methodology described in ISO 9223 and ISO 9224 over the exposure period.</p>

Selecting Controls for Minimizing SARS-CoV-2 Aerosol Transmission in Workplaces and Conserving Respiratory Protective Equipment Supplies

With growing evidence of inhalation of small infectious particles as an important mode of transmission for SARS-CoV-2, workplace risk assessments should focus on eliminating or minimizing such exposures by applying the hierarchy of controls. We adapt a control banding model for aerosol-transmissible infectious disease pandemic planning to encourage the use of source and pathway controls before receptor controls (personal protective equipment). Built on the recognition that aerosol-transmissible organisms are likely to exhibit a dose–response function, such that higher exposures result from longer contact times or higher air concentrations, this control banding model offers a systematic method for identifying a set of source and pathway controls that could eliminate or reduce the need for receptor controls. We describe several examples for workers at high risk of exposure in essential or return to work categories. The goal of using control banding for such workers is to develop effective infection and disease prevention programs and conserve personal protective equipment.

Non-destructive collection survey of the historical Classense Library. Part I: Paper characterisation

An innovative survey was conducted of the collections of the historical Biblioteca Classense, located in the urban area of Ravenna (Northern Italy). The survey aimed to evaluate the current conservation state of the book collections, where 297 paper-based items, including incunabulae, manuscripts and books, dating from the 14th to the 20th century, were selected for analysis. This innovative survey was carried out non-destructively by assessing degradation visually and by measuring NIR spectral data followed by multivariate data analysis. Chemical and physical paper properties, important for paper characterisation and implementation of conservation strategies were determined, including paper type, pH, degree of polymerisation (DP), tensile strength, lignin, protein, and rosin content. This survey provided a significant quantitative dataset for rag paper covering a 600-year period. The analysis of DP changes over time allowed the first experimental estimation of the rate constant for historical rag paper, i.e., (4.2±0.6)·10-7 year-1, which was validated with predictions based on the Collections Demography dose response function for historic paper taking into account the past climate in Ravenna. Statistical methods were employed to describe the correlations between the measured variables and different features of the books, suggesting that the degree of polymerisation can be used as a general proxy for rag paper mechanical strength.