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Background: Work-related musculoskeletal disorders (WMSDs) are one of the most important factors for occupational injuries and disabilities, with the back injuries being the most common work-related injuries in different industries in many developing countries. Objectives: The objectives of the present study were determination of the prevalence of WMSDs symptoms, identification of major risk factors associated with WMSDs symptoms and ergonomics interventions to reduce these disorders. Patients and Methods:This follow-up and interventional study was carried out in a lead mine. Forty persons participated in this study. The Nordic musculoskeletal questionnaire was used to study the prevalence of WMSDs and the quick exposure check (QEC) method was used to assess the physical exposure to risks. Ultimately, data was analyzed using McNamar's and Cochran's tests by SPSS version 11 software. Results:The results revealed that the highest prevalence of musculoskeletal disorders was reported in lower back (57.5%) and knees (50%) during the 12 months prior to the study. After ergonomics interventions, significant reductions in WMSDs were observed at the time of follow-up. According to Cochran's test, significant differences between the pre, four and nine months after the intervention in lower back and knee were observed (P < 0.005). Conclusions: Consistent reductions were observed for all WMSDs disorders at the ninth month of the follow-up. It can be inferred that the use of practical and low-cost methods of engineering and administrative interventions together and monitoring the proper implementation of these interventions during a long time may achieve desired results in reducing musculoskeletal disorders in small scale and poor industries in developing countries.

This article pays attention to the application of an ergonomic risk factors assessment technique so-called "Rapid Upper Limbs Assessment (RULA)" for evaluation of the upper limb musculoskeletal loads due to posture, repetition and force in textile factory. It introduces a practical topic in ergonomics field that can be useful for ergonomists, occupational hygienists, occupational therapists, industrial designers, physiotherapists, rehabilitation specialists, and anthropologists.

Background: In many industries, noise is attributed as the most prevalent harmful agent threatening workers' health. Geographic Information System (GIS) is an applicable surveying tool in civil engineering. But, the use of GIS for noise and hearing loss screening seems to be partly a new approach. Objectives: This study aimed to apply GIS in noise and hearing loss screening in the production hall of a publishing industry. Patients and Methods:A cross-sectional study was conducted on 46 employees working in the production hall of a publishing industry in Iran. First, workers' hearing threshold was examined by Pure-Tone Audiometry (PTA) at 250-8000 Hz frequencies. Then, the production hall area was divided into squares (6 × 6 m 2 ), taking sound pressure levels (SPL) in each square center by a sound level meter (SLM) according to ISO-9612; 2009. Noise and hearing loss maps were drawn, by Arc GIS-9.2, for different areas of the production hall. Results: Noise measurements revealed that total sound pressure levels (SPL) in the production hall ranged from 72.3to 94.5 dBA. From the total area of production hall, 20% of it was found to be exceeding the threshold limit value (SPL ≥ 85 dBA) on the GIS-prepared noise map. Fisher exact test showed a significant difference between hearing losses (HL ≥ 25 dB) in the danger zone (SPL ≥ 85 dB) and the warning zone (85 > SPL ≥ 65 dB) (P = 0.005). Among the workers, 50% of them were in the danger zone and 8.8% of those who were in warning zone had varying degrees of hearing losses. Conclusions: GIS can play an important role in better noise and hearing loss screening through providing a set of facilities such as: converting point data to area ones, possibility of classification in different domains of prepared area data, generation of reports on map, graphic, and table, etc.

Background: Many industrial devices have an excessive vibration which can affect human body systems. The effect of vibration on cochlear histology has been as a debatable problem in occupational health and medicine. Objectives: Due to limitation present in human studies, the research was conducted to survey the influence of vibration on cochlear histology in an animal model. Materials and Methods: Twelve albino rabbits were experimented as: Vibration group (n = 6; exposed to 1.0 m.s -2 r.m.s vertical wholebody vibration at 4 -8 Hz for 8 hours per day during 5 consecutive days) versus Control group (n = 6; the same rabbits without vibration exposure). After finishing the exposure scenario, all rabbits were killed by CO2 inhalation; their cochleae were extracted and fixed in 10% formaldehyde for 48 hours, decalcified by 10% nitric acid for 24 hours. Specimens were dehydrated, embedded, sectioned 5 µm thick and stained with Hematoxylin and Eosin for light microscopy observations. Results: Severely hydropic degenerated and vacuolated inner hair cells (IHCs) were observed in vibration group compared to the control group. Inter and intracellular edema was appeared in supporting cells (SC). Nuclei of outer hair cells (OHCs) seemed to be pyknotic. Slightly thickened basilar membrane (BM) was probably implied to inter cellular edematous. Tectorial Membrane (TM) was not affected pathologically. Conclusions: Whole-body vibration could cause cochlear damages in male rabbits, though vibration-induced auditory functional effects might be resulted as subsequent outcome of prolonged high level vibration exposures.