Identification and classification of factors affecting the non-use of safety harness at height among construction workers in Tehran.

INTRODUCTION: The accident of falling from a height is high among construction workers. Construction workers do not use harnesses. Thus, the present study was conducted to identify the factors affecting the non-use of harnesses among construction workers in Tehran, Iran. MATERIALS AND METHODS: In this study was conducted by interviewing professors and construction workers in order to identify factors affecting the non-use of harness. Factors influencing the non-use of safety harnesses were identified from the workers' point of view. The obtained data were classified and coded using MAXQDA 10 software. After that, the most essential, effective and powerful factors were identified using the degree and intersectionality of social network analysis. RESULTS: According to the interview results, 27 factors were determined as factors affecting the non-use of harnesses by construction workers and divided into four main groups. The four groups were harness design, management factors, harness comfort, and attitudinal factors. Based on the results of the degree centrality, the non-ergonomic design and attitude of the harness inefficiency were identified as the most influential and powerful factors. The betweenness indicator also showed that the non-ergonomic design could mediate other factors in the non-use of the harness. CONCLUSION: The findings showed that by considering various factors such as considering more comfort in the design of the ergonomic harness, it produced a better product. Also, the use of safety harnesses by workers increases.

Design and psychometric analysis of the safety harness usability and comfort assessment tool (SH UCAT).

Purpose: The present study aimed to design a quantitative tool to evaluate the comfort and usability of working at height safety harnesses. Methods: This cross-sectional study was conducted in both qualitative and quantitative sections in 2022. The research steps included field interviews, an expert panel, and compiling the questionnaires for assessing the comfort and usability of the harness. The items of tools were designed based on the qualitative part of the research and review of the literature. The face and content validity of the instrument were assessed. Its reliability was also evaluated using the test-retest method. Results: Two tools were developed including a comfort questionnaire with 13 questions and a usability questionnaire with 10 questions. The Cronbach's alpha coefficients of these instruments were 0.83 and 0.79, respectively. Additionally, the content and face validity indices were 0.97 and 3.89 for the comfort questionnaire and 0.991 and 4 for the usability questionnaire, respectively. Conclusions: The designed tools showed appropriate validity and reliability and could be used to evaluate the comfort and usability of safety harnesses. On the other hand, the criteria used in the designed tools could be employed in user-centered harness designs.

Comparison of physical workload and physical work capacity among municipality cleaners in Shiraz to determine number of workers needed to counterbalance physical workload.

BACKGROUND: Assessing physical workload is the most important step in deciding whether a workload is high and adopting appropriate control strategies to reduce physical workload. This study aimed to compare physical workload and Physical Work Capacity (PWC) among municipality cleaners in Shiraz to determine the number of workers needed to counterbalance physical workload. METHODS: The present cross-sectional study was performed on 97 municipality cleaners in Shiraz. In the first step, the participants' maximum aerobic capacity (VO2-max) was estimated in the laboratory using an ergometer bicycle and the Young Men's Christian Association (YMCA) protocol, based on which the PWC was estimated. Secondly, energy expenditure and heart rate during work were measured using a POLAR400 device in an eight-hour shift. At the end of the work shift, the workers' perceived physical exertion was assessed using a Rating of Perceived Exertion 6-20 (RPE 6-20) Borg scale. In the final stage, the physical workload was assessed based on the results of the two steps. RESULTS: The mean VO2-max of the cleaners and PWC were estimated to be 2.6 ± 0.66 l min-1 and 4.3 ± 1.088 kcal min-1, respectively. The average energy consumed during work was 4.122 ± 1.016 kcal min-1. The overall results of this study showed that physical workload was greater than PWC in 46% of the municipality cleaners. In addition, it was found that 12.45% workforce was required to be added to the street cleaners of Shiraz municipality to reduce the physiological workload on the employed workforce. CONCLUSIONS: With respect to the high level of physical activity in a significant proportion of the cleaners, measures such as increasing the workforce are suggested.

Improving working conditions in an Iranian hospital: a participatory ergonomics approach.

Objectives. The future workshop (FW), as a participatory ergonomics approach, is used to change the actual situation of a system into a preferable one. This study was conducted at a major hospital to identify ergonomic problems and provide appropriate solutions for improving working conditions using the FW technique. Methods. Twenty-five mid-level managers of the hospital participated in a 2-day FW. In the critique phase, the ergonomic problems were thoroughly discussed. After brainstorming followed by structuring and grouping of ideas, 75 ergonomic problems were identified and classified into four groups. Solutions and action plans were proposed to improve working conditions. Results. There were nine problems in the personnel-managerial group. Eighteen action plans were proposed to fix them. Stressful occupational factors were the worst problem in this group. Five problems were characterized in the physical space group and 10 action plans were presented. Seven problems were detected in the equipment group, for which 13 action plans were presented. In the welfare group, six problems and 12 action plans were presented. Conclusion. The results revealed that the FW was an appropriate method to find ergonomic bottlenecks in the hospital and a good basis for devising ergonomic interventions.

Urinary level of un-metabolized parabens in women working in beauty salons.

Parabens are a group of chemical additive extensively utilized in various health care products and ubiquitously observed in the different environmental matrixes. Nevertheless, the exposure of women working in beauty salons to these pollutants is not well-documented. For this purpose, 50.00 women working in beauty salons were chosen as the exposed group (EG) and 35.00 housewives were chosen as the control group (GC). The concentration of methyl paraben (MeP), ethyl paraben (EtP), butyl paraben (BuP), propyl paraben (PrP), benzyl paraben (BzP), heptyl paraben (HepP), and para-hydroxybenzoic acid (4-HB) metabolite were quantified in the collected urine samples. It was seen that paraben sexist with a high detection frequency (DF) in the urine of women working in beauty salons. The results also revealed that the significant difference between the urinary parabens level in the EG and CG (P value < 0.05). The median concentration of Σparaben and HB-4 metabolite in the before exposure (BE) samples was 124.00 and 219.00 µg/L, while in the after exposure (AE) samples, it was 156.00 and 249.00 µg/L, respectively. Moreover, the parabens levels in the AE samples were considerably higher than in BE samples in women working in beauty salons (P value < 0.05). This research also documented that "personal care products (PCPs) usage" can be known as a leading factor for the urinary paraben level in the studied individuals. The median total estimated daily intakes (TEsDI) for MeP, EtP, and PrP for the studied women were obtained as 8.02, 4.57, and 7.88 µg/L respectively. Also, a significant and positive association was observed between EtP, PrP as well as BuP and 8-OhdG (as a DNA oxidative stress biomarker) (P value < 0.01). Further, a significant and positive association was found between EtP as well as BuP and some biomarkers of kidney damage (like uTIMP-1 and uKim-1). Accordingly, it can be stated that women working in beauty salons are at a high risk in terms of DNA oxidative stress and kidney damage.

Evaluation of a passive low-back support exoskeleton (Ergo-Vest) for manual waste collection.

The purpose of study was to determine the biomechanical, physiological, and subjective effect of a Passive Exoskeleton device (called Ergo-Vest) among 20 waste collectors in the working environment. Compression force and moment on L4/L5 related to 400 critical postures of the participants were estimated using the 3DSSPP software. The heart rate and energy expenditure are measured as the physiological strain using the Polar RS400 Heart Rate Monitor. Borg scale perceived exertion, system usability scale, and ergonomic design indicators of the device were collected as the subjective parameters. Compression force and moment on L4/L5 disc were decreased when the Ergo-Vest was utilised. There was no significant difference in energy expenditure and heart rate with and without the device. The workers' perceived physical exertion was decreased while using the Ergo-Vest. From the perspective of end users, the usability and ergonomic design features of the Ergo-Vest was acceptable. Practitioner summary: The prevalence of musculoskeletal disorders is high among the Iranian waste collectors. To mitigate this occupational problem, the effect of a passive exoskeleton for lower-back support (Ergo-Vest) was investigated on the workers' spine loading, physiological parameters, and perceived physical exertion. The result shows spine force reduction and lower subjective responses.

Psychological and physical job demands, decision latitude, and work-related social support among Iranian waste collectors.

Waste collection is known as a stressful and physically demanding job in low/middle income countries. This study aimed to assess the psychological and physical job demands, decision latitude, and work-related social support among Iranian waste collectors. In this cross-sectional study, field observation, video capture, and unstructured interviews were performed to understand the process of waste collection. Data were collected from 200 waste collectors of Shiraz city using a demographic/work characteristics questionnaire and a job content questionnaire (JCQ). Logistic regression analysis was used for the prediction of independent variables affecting job content dimensions. A p < 0.05 was considered to be statistically significant. Results show that the rate of municipal solid waste (MSW) generation in Shiraz city was 0.576 kg/capita/day, which translates into about 1076 tons of waste per day per the current population of 1,869,001. The total amount of MSW produced in Shiraz over a four-year period from 2014 to 2017 were 346,093, 363,505, 392,869, and 400,863 tons, respectively. About half of the waste collectors reported high levels of psychological and physical job demands. More than half were concerned with the low level of decision latitude and social support in the workplace. Night-workers (OR = 3.29) and smokers (OR = 2.75) reported higher psychological job demands than day-workers and non-smokers, respectively. Decision latitude and social support were inversely associated with the level of education (OR = 1.90), and daily working time (OR = 2.46), respectively. Based on the Demand-Control-Support Model, waste collectors were exposed to relatively high levels of job stress associated with occupational risk factors.

Public exposure to radiofrequency electromagnetic fields in everyday microenvironments: An updated systematic review for Europe.

Communication technologies are rapidly changing and this may affect public exposure to radiofrequency electromagnetic fields (RF-EMF). This systematic review of literature aims to update a previous review on public everyday RF-EMF exposure in Europe, which covered publications until 2015. From 144 eligible records identified by means of a systematic search in PubMed, Embase and Web of Knowledge databases, published between May 2015 and 1 July 2018, 26 records met the inclusion criteria. We extracted quantitative data on public exposure in different indoors, outdoors and transport environments. The data was descriptively analyzed with respect to the exposure patterns between different types of environments. Mean RF-EMF exposure in homes, schools and offices were between 0.04 and 0.76 V/m. Mean outdoor exposure values ranged from 0.07 to 1.27 V/m with downlink signals from mobile phone base stations being the most relevant contributor. RF-EMF levels tended to increase with increasing urbanity. Levels in public transport (bus, train and tram) and cars were between 0.14 and 0.69 V/m. The highest levels, up to 1.97 V/m, were measured in public transport stations with downlink as the most relevant contributor. In line with previous studies, RF-EMF exposure levels were highest in the transportation systems followed by outdoor and private indoor environments. This review does not indicate a noticeable increase in everyday RF-EMF exposure since 2012 despite increasing use of wireless communication devices.

Cancer incidence and mortality among firefighters.

Firefighters are exposed to both known and suspected carcinogens. This study aims to systematically review the literature on the association of firefighting occupation and cancer incidence and mortality, overall and for specific cancer sites. A systematic review using PubMed, Embase, and Web of Science was performed up to January 1, 2018. We extracted risk estimates of cancers and calculated summary incidence risk estimates (SIRE), summary mortality risk estimates (SMRE), and their 95% confidence intervals (CI). Publication bias and risk of bias in individual studies were assessed using Begg's and Egger's tests and the Newcastle-Ottawa scale (NOS), respectively. We included 50 papers in the review and 48 in the meta-analysis. We found significantly elevated SIREs for cancer of the colon (1.14; CI 1.06 to 1.21), rectum (1.09; CI 1.00 to 1.20), prostate (1.15; CI 1.05 to 1.27), testis (1.34; CI 1.08 to 1.68), bladder (1.12; CI 1.04 to 1.21), thyroid (1.22; CI 1.01 to 1.48), pleura (1.60; CI 1.09 to 2.34), and for malignant melanoma (1.21; CI 1.02 to 1.45). We found significant SMREs of 1.36 (1.18 to 1.57) and 1.42 (1.05 to 1.90) for rectal cancer and Non-Hodgkin's lymphoma, respectively. Considering the significantly elevated risk of some cancers in this occupational group, we suggest improving preventive measures and securing adequate and relevant medical attention for this group. Further studies with more accurate and in-depth exposure assessments are indicated.

Coefficient of friction, walking speed and cadence on slippery and dry surfaces: shoes with different groove depths.

Objective. The present study aimed to determine the coefficient of friction (COF), walking speed (WS) and cadence while walking on slippery and dry surfaces using shoes with different sole groove depths to predict likelihood of fall. Background. Design of shoe sole groove is crucial to prevent slipping during walking. Methods. 22 healthy young men (mean age 24.5, body mass index 22.5) volunteered for this semi-experimental study. Six different conditions of the test (combination of three shoes and two surfaces) were defined and the condition was repeated three times. In total, 396 trials (22 subjects × 3 groove depths × 2 surfaces × 3 times) were obtained for data analysis. COF was recorded by force platform at 1000 Hz and walking parameters recorded using 3D motion analysis with six infrared cameras at 200 Hz. Results. The highest COF was obtained from the deepest groove depth (5.0 mm) on both dry and slippery surfaces. The COF on slippery surfaces was significantly lower in comparison with dry surfaces. WS and cadence were not significantly different on dry and slippery surfaces. Conclusion. The deeper groove is better to prevent slipping because the COF increases by increasing the shoe sole groove depth. WS did not change on dry and slippery surfaces.

Individual, physical, and organizational risk factors for musculoskeletal disorders among municipality solid waste collectors in Shiraz, Iran.

In Iran-Shiraz, municipal solid waste is collected manually requiring strenuous physical activities. This study was conducted to determine the prevalence rate of musculoskeletal disorders (MSDs) and its associated risk factors. Two hundred male waste collectors participated in this cross-sectional study, in which task analysis followed by motion and timeline analysis were performed. The data were collected using demographic, occupation-specific physical and organizational demands, and Nordic musculoskeletal questionnaires. Logistic regression analysis was used for identifying independent risk factors for MSDs. Ten motions observed during waste collection, and the most physical and organizational demands were related to the running along with bag carriage, and the time pressure, respectively. About 39% and 36.5% of the workers reported very high physical and psychological workloads, respectively. Totally, 92.5% of waste collectors reported MSDs symptom at least in one body region during the last 12 months. Lower back and knee injuries were more prevalent and more severe. Some individual factors (age, body weight, and waste collecting duration), physical demands (lifting bag/bucket, pulling/pushing waste container, walking along with bag/bucket carriage, and jumping up/down on the garbage truck), and organizational demands (low vacation and high decision authority) were the most important risk factors for developing MSDs.

Assessment and virtual redesign of a manual handling workstation by computer-aided three-dimensional interactive application.

BACKGROUND: Manual handling of bags which imposes frequent forces and stresses on body parts is a common task that many workers have to perform every day. The present study aimed to assess the postural risk and imposed forces due to manual handling and loading of sugar bags. METHODS: This study was conducted on male warehouse workers of a sugar manufacturing plant. Rapid upper limb assessment (RULA) was used to assess the risks of awkward postures and computer-aided three-dimensional interactive application to estimate the forces and moments. RESULTS: RULA final scores were estimated to be 7 and 3 before and after the virtual redesign, respectively. Postures B and E obtained the highest compression forces and moments. The compression forces were higher than the action limit (AL) in all postures before the redesign and exceeded the maximum permissible limit (MPL) in posture E. After the redesign, these forces were reduced below the AL and MPL. Moreover, the shearing forces were lower than the AL and MPL in all postures. CONCLUSIONS: The main risk factors were heavy weight and poor control of sugar bags. Virtual redesign can diminish bending and twisting postures, and, therefore, some resulting forces and moments.

Use of the Finnish method to quantify the ergonomic properties in an office environment among the workplaces in an Electricity Distribution Company in West Tehran Province.

BACKGROUND: The workplace plays an important role in workers' performances, but most workplaces have not been designed and equipped in keeping with primary ergonomic principles. Ignoring these principles can cause ergonomic risk factors, difficulties for workers, and damage to workers' health. The aim of this study was to identify acceptable ergonomic properties in workplaces in order to determine and investigate the aspects of workstations that cause occupational discomfort. To accomplish this aim, we used the Finish method to evaluate workstations in an electricity distribution company in Tehran. METHODS: This cross sectional study was conducted for all of the workstations in an electrical power distribution company using the census method. The desired information was collected through objective observation using the Finish checklist of ergonomic issues in the workplace. Then, we used SPSS version 16 to analyze the information. RESULTS: In 11.2% of the workstations, none of the ergonomic principles was considered, so workers' bodied were not situated appropriately while they were working. In 31% of the cases, lighting ranged between 10% and 50% of the recommended amount, and some of the workers appeared to be in a slight daze. In 42.3% of the cases, the temperature in the workplace was in the range of 25 to 27°C. In 42.3 and 52.3% of the cases, ratings of noise were 2 and 3, respectively, indicating that the noise levels were 60-70 dB and 70-80 dB, respectively. CONCLUSION: The findings of this study can be used to determine ergonomic deficiencies in workstations so they can be resolved. Based on our investigation, it was found that the workstations, first and foremost, had significant defects in terms of work components. Furthermore, there were some irritating problems concerning noise and concerning comfort levels related to the high temperature.