Archives Of Occupational Health
Volume:3 Issue: 2, Apr 2019

Low-frequency noise as a detrimental occupational and environmental factor which can cause noise annoyance. In addition to noise, factors such as sensitivity and awareness of adverse health effects of noise seem to play an important role in causing annoyance. Therefore, this study aimed to investigate the association of noise annoyance and loudness perception caused by exposure to low-frequency noise with noise sensitivity. To achieve this goal, 80 students were exposed to low-frequency noise exposure at 65 dBA in an acoustic room. After one hour of exposure, the subjects completed the Weinstein's Noise Sensitivity Scale, Loudness Perception Scale, and Noise Annoyance Scale. Data were analyzed using Mann-Whitney, Kruskal-Wallis test and the Multivariate Analysis of variance (MANOVA). The results showed that the mean score of noise annoyance and loudness perception was significantly higher in the group with high noise sensitivity. Also, increasing the awareness of the harmful effects of noise significantly increased the level of annoyance and loudness perception of individuals. The results of MANOVA showed that noise sensitivity has a significant effect on both the response variables. Also, awareness of the harmful effects of noise only affects loudness perception. The interaction effect of two independent variables was not significant on any of the response variables . In general, it can be concluded that noise sensitivity and awareness of the harmful effects of noise are two important factors that exacerbate the annoyance caused by exposure to low-frequency noise.

One of the effective factors on controlling fire stations' system is situational awareness potentially varying in different scenarios. This study will investigate the relationship between situational awareness, as a set of the cognitive attributes, and ergonomics. It has been proved that situational awareness improves the performance of an organization's staff. This is semi-experimental research in which 30 firefighters from Isfahan urban fire stations participated. Materials used in this research are brachial pressure, a pulse oximeter (fingertip), and Situation Awareness Assessment Approaches. In each step, five firefighters from one fire station were tested twice. Average score of situational awareness did not change significantly after the fire station alarm compared to before it. After the alarm, physiological variables such as blood pressure and heart rate decreased and increased, respectively. The results showed work experience played a significant role in the score of situational awareness and increase in heartbeat. Given the lack of effect of alarm but the effect of work experience on situational awareness, experienced firefighters’ experiences and training can be used for improving situational awareness in young and inexperienced firefighters.

Exposure to noise is an important safety and health problem in many industries. The rail transport industry is one of the industries involved with this problem due to the variety of equipment and its scope.  The present study aimed to evaluate noise pollution and determine the sources of noise at Mashhad railway station. In this descriptive-analytic study in 2014, the departments with noise pollution were identified and studied based on an initial assessment of all parts of the railway station. Noise was measured in ten departments and units. The environmental and local noise was measured by calibrated sound level meter Model CEL485 in A and C networks according to ISO9612 and ISO 11200 standards. Then the collected data entered and analyzed in Surfer V.10 and Excel software. The results of noise measurement showed that the average sound pressure level in units of Diesel GM, repair shop, refueling station, Diesel Siemens, and platform 3 was in hazard range. The results of measurement of the average sound pressure level in departments and units and the isosonic mappings drawn by Surfer V.10 software as well as the results of the average noise level in GM diesel showed that GM diesel (with LP=87.60 dB (A)) is the main source of noise at Mashhad railway station. The results of this study showed that diesel engines, gearboxes, moving trains, and beeps are the main noise generator components in GM diesel. The highest mean sound pressure level among these components was related to the diesel engine with an average sound pressure level of 87.60 dB (A). In general, the average sound pressure level of this diesel was 95.45 dB in the dominant frequency of 63 Hz. Based on the result of this study, GM diesel plays a major role in transporting at Mashhad railway station, accordingly the design and implementation of technical control measures such as chamber and enclosure of noise generator components are essential to reduce the average sound pressure level.

Musculoskeletal disorders (MSDs) are among the most common occupational disorders. WMSDs are known as an influential factor in work productivity. Also, the safety climate plays an important role in the occupational health of individuals. The purpose of this study was to investigate the relationships between WMSDs, work productivity and safety climate. This quantitative, theoretical and descriptive study was performed on 344 employees. The samples were randomly selected. Data were gathered by means of the Body Map, Safety Climate, and Work Productivity questionnaires. This study was conducted on different types of jobs from three types of industries. STATISTICA software was used for all data analyses (SPSS Version 23) with a significant level of P <0.01. One-way analysis of variance was used to examine the significant differences between industries and jobs, which indicated that there is a statistically significant difference. Correlations between the WMSDs, work productivity, and safety climate was tested using the parametric Pearson correlation coefficient that showed a significant negative correlation between WMSDs with work productivity and safety climate. Positive correlations were found between safety climate and work productivity. In general, safety climate and work productivity are important for the health and safety of employees, and this study showed that it might be also important for employees in construction industries.

Particulate matter air pollution is one of the most important risk factors for cardiovascular and respiratory diseases. By increasing the number of mineral industries in the two past decades, workers in these industries are exposed to pathogenic respirable particulate matter pollutants. Cluster analysis is a multivariate statistical analysis method. Clustering creates groups or classes that the difference between the sub-groups samples is less than the difference between the groups. Therefore, this study assigns the cluster analysis to air sampling data collected from the various units of a tile factory. In this observational study, sampling from the respiratory zone of 93 workers in a tile and ceramic factory for both respirable and inhalable particles were performed. Sampling of inhalable particle based on NIOSH_0500 protocol and respirable particles based on NIOSH_0600 was conducted. Data were analyzed by both R 3.2.2 software and hierarchical cluster analysis with Ward link. 92.47% of Workers were exposed to respirable particles less than TLV and 39.8% of them were exposed to inhalable particles more than TLV. The maximum average exposure for respirable particles 13.04 mg/m3 and inhalable particles 84.88 mg/m3 is respectively reported for crusher unit. The lowest average exposures to respirable (0.41 mg/m3) and inhalable (min=1.74 mg/m3) particles were observed in the glaze line division. Since the workers are exposed to concentrations more than the threshold limit value of respirable particles, and especially inhalable particles in some units, appropriate control measures must be considered to prevent possible consequences.

Musculoskeletal disorders are one of the most common factors that lead to occupational injuries among hospital staff. Considering the key role of hospital staffs in providing health services to patients, this study was conducted to assess risk factors that are effective on low back pain and the use of adaptive neuro-fuzzy inference system (ANFIS) model to predict it. This cross-sectional study was conducted in 90 nurses of the Isfahan hospitals in 2018. First, the risk factors that affect pain in the lumbar region was assessed, then a model with the precision of 0.91% to predict low back pain was developed using the ANFIS by the MATLAB2016a software. First,  linear regression model showed four risk factors repetitive movements, long-standing, bending of the back, and carrying heavy objects were the most significant ones compared to other risk factors associated with musculoskeletal disorders. After a study of these risk factors in the ANFIS, various tests were conducted and the best model with a confidence level of 91% was selected as the model. The ANFIS can be used as an appropriate tool to predict lower back pain.

The aim of this study is to investigate the relationship between the principles of ergonomics in both material and immaterial dimensions and employee productivity in (IOOC). Immaterial dimension of ergonomics was measured by variables such as freedom of activity at work and job feedback, and the material dimension of ergonomics was measured by factors such as workplace design and body position. The variables of the productivity construct based on the ACHIEVE model include ability, transparency, assistance, incentive, evaluation, credit, and environment. Each of the constructs was measured by an appropriate questionnaire filled out by 170 operational employees of the Company. Descriptive variables were analyzed using Structural Equation Modeling based on the PLS method to investigate the research hypotheses. The level of employee productivity and ergonomics of the workplace in the IOOC are not desirable due to difficult working conditions and lack of managers' paying attention. The hypothesis of the effectiveness of ergonomics on productivity was confirmed and the material dimension was more effective on employee productivity than the immaterial dimension of human factors. Due to the difficult conditions of the operational units of oil companies, attention should be directed to the physical conditions of the work environment. To improve employee productivity, certain plans for human resource development and management, revision of the designing of the work environment, and work measurement are proposed.

Human beings are always exposed to natural and artificial sources of ionizing and non-ionizing radiation. Welding is one of the jobs whose professionals may expose ultraviolet and infrared radiation and suffer from the resulting complications. Therefore, the purpose of this study is to determine the exposure to ultraviolet and infrared radiation in welders. This study was conducted on 70 welders in Bojnord city. The UV meter and the IR meter (Hanger) were used to conduct measurements. The measurements were conducted at 10, 50 and 100-cm distances from the welding site, and at two heights, the wrists and eyes. Eye symptoms caused by radiation were collected and recorded by checklist and observation. Data were analyzed by descriptive statistics, t-test, and ANOVA. The average age of the workers was 37(10) years, the average work experience was 18(11) years, and the average radiation exposure duration was 3.5(2) hours. The average ultraviolet radiation measured was 4.13(4.88) W/m2 and the average infrared radiation was 17.13(12.54) W/m2 at the welding stations. In 84% ​​of the stations, the measured ultraviolet radiation and in 100% of them, the measured infrared radiation was standard. There were 58 (83%) welders with at least one eye problem. There was a significant relationship between the amount of radiation, and the type of welding, exposure duration, and work history, but no significant relationship between the amount of radiation and height and distance of measurement. In order to prevent eye symptoms in welders, it is recommended to reduce the duration of exposure of the welders or welders should do welding during the day intermittently and use suitable personal protective equipment, especially a suitable welding mask, during welding.