Effectiveness of a Light-Weight Ice-Vest for Body Cooling While Wearing Fire Fighter’s Protective Clothing in the Heat

The aim of the study was to examine the effects of wearing an ice-vest (ca 1 kg) on physiological and subjective responses in fire fighters. The experiments were carried out on a treadmill in a hot-dry environment. The physical cooling effect of the ice-vest was measured with a thermal manikin. The ice-vest effectively reduced skin temperatures under the vest. On average, heart rate was 10 beats/min lower, the amount of sweating was reduced by 13%, and subjective sensations of effort and warmth were lower during work with the ice-vest compared to work without it. Thermal manikin tests indicated that the useful energy available from the vest for body cooling was rather high (58%). In conclusion, the ice-vest reduces physiological and subjective strain responses during heavy work in the heat, and may promote efficient work time by 10%.     

Long-Term Prediction of Traffic Accident Record From Bus Driver Celeration Behavior

Driver celeration (speed change) behavior of bus drivers measured a number of times was used to predict their culpable accidents over increasing time periods. It was found that predictive power was considerable (>.30 correlation) over 5 years of time with aggregated celeration (mean of repeated measurements) as independent variables, and there were also indications that power reached even further, although too low Ns made these results unreliable. Similarly, there were indications of even stronger correlations with increased aggregation of celeration values. The results were discussed in terms of the methodology needed to bring out such results, and the stability of accident-causing behavior over time.     

Performance of Firefighters’ Protective Clothing After Heat Exposure

Heat and mechanical protection properties of 6 fabric combinations commonly used in firefighters’ protective clothing were assessed before and after different heat treatment. It was shown that after heat exposure, the values obtained were generally lower than in the original state. The mechanical properties of the materials were more affected by heat than by heat protective properties. In 2 cases, degradation started before a visible change in the material could be observed, which might be potentially dangerous for the end user who will not realize the alteration of the material.     

Child Abuse Investigation: Police Officers and Secondary Traumatic Stress

Child protection is an area of police work which has expanded in the last decade, leading to an increase in the number of police officers working in departments which specialise in investigating cases of child abuse. Police officers in this field may be at greater risk of experiencing secondary traumatic stress but there remains a paucity of research in this area of policing. Analogies can be drawn to existing research in policing and with social service workers involved in child protection. The paper finishes off with implications for police forces to ensure safe working environments and appropriate counselling for employees.     

A Fuzzy Model for Assessing Risk of Occupational Safety in the Processing Industry

Abstract

Managing occupational safety in any kind of industry, especially in processing, is very important and complex. This paper develops a new method for occupational risk assessment in the presence of uncertainties. Uncertain values of hazardous factors and consequence frequencies are described with linguistic expressions defined by a safety management team. They are modeled with fuzzy sets. Consequence severities depend on current hazardous factors, and their values are calculated with the proposed procedure. The proposed model is tested with real-life data from fruit processing firms in Central Serbia.     

Occupational Exposure to Natural UV Radiation and Premature Skin Ageing

The skin is the part of the human body most vulnerable to ultraviolet (UV) radiation. The spectrum of the negative effects of UV radiation on the skin ranges from acute erythema to carcinogenesis. Between these extreme conditions, there are other common skin lesions, e.g.,photoageing. The aim of this study was to assess the skin for signs of photoageing in a group of 52 men occupationally exposed to natural UV radiation. There were 2 types of examinations: an examination of skin condition (moisture, elasticity, sebum, porosity, smoothness, discolourations and wrinkles) with a device for diagnosing the skin, and a dermatological examination. The results of both examinations revealed a higher percentage of skin characteristics typical for photoageing in outdoor workers compared to the general population.     

The determinants of employee participation in occupational health and safety management

This article focuses on employee direct participation in occupational health and safety (OHS) management. The article explains what determines employee opportunities to participate in OHS management. The explanatory framework focuses on safety culture and safety management at workplaces. The framework is empirically tested using Estonian cross-sectional, multilevel data of organizations and their employees. The analysis indicates that differences in employee participation in OHS management in the Estonian case could be explained by differences in OHS management practices rather than differences in safety culture. This indicates that throughout the institutional change and shift to the European model of employment relations system, change in management practices has preceded changes in safety culture which according to theoretical argument is supposed to follow culture change.     

Ergonomic analysis of working postures using OWAS in semi-trailer assembly,applying an individual sampling strategy

In semi-trailer assembly, workers are exposed to several physical risk factors. Awkward working postures have not yet been investigated in semi-trailer assembly, although they are known to be a major risk factor for musculoskeletal disorders. We therefore conducted a comprehensive ergonomic analysis of working postures using the Ovako working posture analysing system (OWAS), with an individual sampling strategy. The postural load in semi-trailer assembly was assessed on the basis of 20,601 observations of 63 workers executing a representative set of nine work tasks. According to the OWAS, the postural load of various working postures and body part positions may have a harmful effect on the musculoskeletal system. We therefore give examples of corrective measures that could improve awkward working postures. Applying an individual sampling strategy was revealed to have advantages over a collective strategy, so this is recommended for future ergonomic analyses.     

Experimental investigation of spark ignition energy in kerosene,hexane, and hydrogen

Quantifying the risk of accidental ignition of flammable mixtures is extremely important in industry and aviation safety. The concept of a minimum ignition energy (MIE), obtained using a capacitive spark discharge ignition source, has traditionally formed the basis for determining the hazard posed by fuels. While extensive tabulations of historical MIE data exist, there has been little work done on ignition of realistic industrial and aviation fuels, such as gasoline or kerosene. In the current work, spark ignition tests are performed in a gaseous kerosene–air mixture with a liquid fuel temperature of 60 °C and a fixed spark gap of 3.3 mm. The required ignition energy was examined, and a range of spark energies over which there is a probability of ignition is identified and compared with previous test results in Jet A (aviation kerosene). The kerosene results are also compared with ignition test results obtained in previous work for traditional hydrogen-based surrogate mixtures used in safety testing as well as two hexane–air mixtures. Additionally, the statistical nature of spark ignition is discussed.     

Experimental investigation of hydrogen–air deflagrations and detonations in semi-confined flat layers

This paper presents results of an experimental investigation on the deflagration and deflagration-to-detonation transition (DDT) in an obstructed (blockage ratio BR = 50%), semi-confined flat layer filled with uniform hydrogen–air mixtures. The effect of mixture reactivity depending on flat layer thickness and its width is studied to evaluate the critical conditions for sonic flame propagation and the possibility for detonation onset. The experiments were performed in a transparent, rectangular channel with a length of 2.5 m. The flat layer thickness was varied from 0.06 to 0.24 m and the experiments were performed for different channel widths of 0.3, 0.6 and 0.9 m. The experimental results show flame velocity vs. hydrogen concentration for different thicknesses and widths of the semi-confined flat layer. Three different flame propagation regimes were observed: slow subsonic flame (M << 1), sonic deflagration (M ～ 1) and detonation (M >> 1). It is shown that flame acceleration (FA) to sonic speed is independent of the width of the flat layer. The critical expansion ratio for effective flame acceleration to sonic speed was found to be linearly dependent on the reciprocal layer thickness.