The influence of confounding factors on the relationship between muscle contraction level and MF and MPF values of EMG signal: a review.

The purpose of this article is to gather results of studies on the relationship between median frequency (MF) and mean power frequency (MPF) and the level of muscle contraction, and to use those results to discuss the differences in the trends according to factors related to measurement technique and subject. Twenty-one studies with 63 cases for upper limb muscles and nine studies with 31 cases for lower limb muscles were analysed. Most results showed an increase in parameters with an increased level of muscle contraction, only some studies showed a decrease.

The concept of resilience in OSH management: a review of approaches.

The concept of resilience has become very popular, especially in the 21st century. This concept is applicable to many fields, from mechanics to a broad range of social sciences. Resilience has even become part of the national and global policies of the USA, the United Nations and the European Commission.

Analysis of occupational accidents: prevention through the use of additional technical safety measures for machinery.

This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005-2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures.

Analysis of noise pollution in an andesite quarry with the use of simulation studies and evaluation indices.

This paper presents the verification of two partial indices proposed for the evaluation of continuous and impulse noise pollution in quarries. These indices, together with the sound power of machines index and the noise hazard index at the workstation, are components of the global index of assessment of noise hazard in the working environment of a quarry. This paper shows the results of acoustic tests carried out in an andesite quarry.

Polish adaptation of three self-report measures of job stressors: the Interpersonal Conflict at Work Scale, the Quantitative Workload Inventory and the Organizational Constraints Scale.

Aim: The objective of the present study was to test the psychometric properties, reliability and validity of three job stressor measures, namely, the Interpersonal Conflict at Work Scale, the Organizational Constraints Scale and the Quantitative Workload Inventory.

Method: The study was conducted on two samples (N = 382 and 3368) representing a wide range of occupations. The estimation of internal consistency with Cronbach's α and the test-retest method as well as both exploratory and confirmatory factor analyses were the main statistical methods.

Multibody model of the human upper extremity for fracture simulation.

About 3.8 million people are injured in accidents at work in Europe every year. The resulting high costs are incurred by the victims themselves, their families, employers and society.

Workstations for people with disabilities: an example of a virtual reality approach.

This article describes a method of adapting workstations for workers with motion disability using computer simulation and virtual reality (VR) techniques. A workstation for grinding spring faces was used as an example. It was adjusted for two people with a disabled right upper extremity.

Corrosion of connectors used in equipment protecting against falls from a height.

Connectors are commonly found in personal equipment protecting against falls from a height. They are typically used outdoors and exposed to atmospheric factors, which can result in corrosion. This article presents the results of a study involving exposure of connectors to experimental corrosive media - neutral salt spray (NSS), acid salt spray (ASS), and seawater mist (for elements made of carbon steel and non-ferrous metals) - and to experimental conditions simulating the processes of pitting, stress, and intercrystalline corrosion (for equipment made of s`tainless steel).

Using lagging and leading indicators for the evaluation of occupational safety and health performance in industry.

Improvement of occupational safety and health (OSH) management is closely related to the development of OSH performance measurement, which should include OSH outcomes (e.g., occupational accidents), OSH inputs (including working conditions) and OSH-related activities.

Selected aspects of absence at work and work-related health problems in Polish enterprises.

Workers' working conditions, work-related health problems and sickness absence are interdependent factors. Both workers' health problems and their absence are adverse events which generate significant costs for both Poland's Social Insurance Institution (ZUS) and employers. Despite the related burdens, it is difficult to assess the number of workers who experience work-related health problems, to indicate the share of those workers who have been unfit for work owing to such disorders and to indicate the types of workers' disorders which are caused by factors the workers are exposed to in the working environment.

Radiofrequency electromagnetic radiation exposure inside the metro tube infrastructure in Warszawa.

Antennas from various wireless communications systems [e.g. mobile phones base transceiver stations (BTS) and handsets used by passengers, public Internet access, staff radiophone transmitters used between engine-drivers and traffic operators] emitting radiofrequency electromagnetic radiation (RF-EMR) are used inside underground metro public transportation.

Exposure to flour dust in the occupational environment.

Exposure to flour dust can be found in the food industry and animal feed production. It may result in various adverse health outcomes from conjunctivitis to baker's asthma. In this paper, flour dust exposure in the above-mentioned occupational environments is characterized and its health effects are discussed.

Heart rate variability (HRV) during virtual reality immersion.

The goal of the study was assessment of the hour-long training involving handling virtual environment (sVR) and watching a stereoscopic 3D movie on the mechanisms of autonomic heart rate (HR) regulation among the subjects who were not predisposed to motion sickness. In order to exclude predispositions to motion sickness, all the participants (n=19) underwent a Coriolis test. During an exposure to 3D and sVR the ECG signal was continuously recorded using the Holter method.

Light transmission through intraocular lenses with or without yellow chromophore (blue light filter) and its potential influence on functional vision in everyday environmental conditions.

In this research the factors used to evaluate the light transmission through two types of acrylic hydrophobic intraocular lenses, one that contained yellow chromophore that blocks blue light transmission and the other which did not contain that filter, were defined according to various light condition, e.g., daylight and at night.

Analysis of the selected optical parameters of filters protecting against hazardous infrared radiation.

The paper analyses the selected optical parameters of protective optic filters used for protection of the eyes against hazardous radiation within the visible (VIS) and near infrared (NIR) spectrum range. The indexes characterizing transmission and reflection of optic radiation incident on the filter are compared. As it follows from the completed analysis, the newly developed interference filters provide more effective blocking of infrared radiation in comparison with the currently used protective filters.

Difficulties in applying numerical simulations to an evaluation of occupational hazards caused by electromagnetic fields.

Due to the various physical mechanisms of interaction between a worker's body and the electromagnetic field at various frequencies, the principles of numerical simulations have been discussed for three areas of worker exposure: to low frequency magnetic field, to low and intermediate frequency electric field and to radiofrequency electromagnetic field. This paper presents the identified difficulties in applying numerical simulations to evaluate physical estimators of direct and indirect effects of exposure to electromagnetic fields at various frequencies. Exposure of workers operating a plastic sealer have been taken as an example scenario of electromagnetic field exposure at the workplace for discussion of those difficulties in applying numerical simulations.

Authentic leadership, social support and their role in workplace bullying and its mental health consequences.

The aim of this study was to show how authentic leadership is related to social support and exposure to workplace bullying and how these variables are related to mental health. For our sample of 820 office workers employed in different Polish organizations and sectors, social support from supervisors moderated the relationship between authentic leadership and workplace bullying. Social support from co-workers moderated the relationship between workplace bullying and mental health and authentic leadership moderated the relationship between workplace bullying and mental health.

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.

The use of a global index of acoustic assessment for predicting noise in industrial rooms and optimizing the location of machinery and workstations.

This paper describes the results of a study aimed at developing a tool for optimizing the location of machinery and workstations. A global index of acoustic assessment of machines was developed for this purpose. This index and a genetic algorithm were used in a computer tool for predicting noise emission of machines as well as optimizing the location of machines and workstations in industrial rooms.

Chronic musculoskeletal disorders as risk factors for reduced work ability in younger and ageing workers.

Aims: The aim of the study was to assess the occurrence and intensity of musculoskeletal pain as a risk factor for reduced work ability.

Methods: In total, 1449 workers participated in the study, 64% were younger workers (<45 years old, M 31.4); 36% were ageing workers (≥45 years old, M 50.

Psychometric properties of the Polish version of Karasek's Job Content Questionnaire.

Aim: The objective of this study was to test the psychometric properties of selected scales, namely, Decision Latitude, Psychological Job Demand, Social Support and Job Insecurity, from the Polish version of Karasek's 29-item Job Content Questionnaire (JCQ).

Method: The study covered 2626 workers from a wide range of occupations. Estimation of internal consistency with Cronbach's α, and both exploratory factor analysis (with principal axis method) and confirmatory factor analysis were the main statistical methods.

Evaluation of the toxic potency of selected cadmium compounds on A549 and CHO-9 cells.

Cytotoxicity of cadmium sulphide, oxide and chloride was tested using A549 and CHO-9 cells. Metabolic activity of cells (MTT test) and cell membrane permeability (NRU test) were used as cytotoxicity endpoints. The results revealed unexpectedly low toxicity of cadmium sulphide as compared to chloride and oxide.

Occupational exposure to noise from authorized emergency vehicle sirens.

Warning signals generated by sirens of authorized emergency vehicles should be audible and recognizable to all road users. Currently, there is no legislation in Poland defining sound pressure levels (SPLs) of audible warning signals generated by sirens of authorized emergency vehicles. Measured A-weighted SPLs of those signals range between 104 and 108 dB.

Comparative study of upper limb load assessment and occurrence of musculoskeletal disorders at repetitive task workstations.

This study explored the relationship between subjectively assessed complaints of pain in the arm, forearm and hand, and musculoskeletal load caused by repetitive tasks. Workers (n=942) were divided into 22 subgroups, according to the type of their workstations. They answered questions on perceived musculoskeletal pain of upper limbs.

Evaluation of discomfort glare in the 50+ elderly: experimental study.

Objectives: The aim of the study was to analyze discomfort glare sensation in subjects aged 50 years and more in comparison with younger subjects (i.e. younger than 35 years of age).