Journal of Health and Safety at Work

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Introduction: Risk assessment of Toxic or hazardous chemicals enables the Industrial Hygienists to make the appropriate decision in providing healthy work place. This project was conducted in an assembling plant,(4workshop) of an Automobile Industry in IRAN with 2 types of welding operations, including GMAW (CO2 welding) and Spot resistance welding operations.

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Method and Materials: Welders` exposures were assessed via collecting 143 breathing zone air samples based on NIOSH 0500 method. Risk assessment was carried out using Singapore recommended method.

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Results: Finding showed that the mean of welders exposure in GMAW and Spot resistance welding operations 5.61 ± 5.78and 2.38± 2.15 mg/m3, respectively(p<0.05). The results showed that in GMAW welders had the highe exposure in comparison with Spot resistance welders (p<0.05). The findings also demonstrated that the risk rate of GMAW welders were high, while this rate for Spot resistance was low.

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Conclusion: more hygienic attention is needed for GTAW welders. Control approaches are required including effective engineering control, conduct air monitoring, biological monitoring training, adopt respiratory protection program, develop and implement safe and correct work procedures and finally reassess the risk after all the controls have been done.

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Introduction: Occupational exposure to manganese can cause neurobehavioral symptoms. The aim of present study was to survey neurobehavioral symptoms of welders exposed to manganese- containing welding fumes and compare the frequency of these symptoms with unexposed group.

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Material and Method: Twenty seven of welders as exposed group, and 30 administrative workers as unexposed controls, were participated in this study. Neurobehavioral symptoms data were gathered using Q16 questionnaire. Manganese concentrations were determined according to the NIOSH 7300 method. After preparing of blood samples using microwave assisted acid digestion method, all samples were analyzed to determine manganese by graphite furnace- atomic absorption spectroscopy (GF-AAS).

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Result: The mean exposure to air manganese was 0.023± 0.012 mg/m3. Manganese concentrations in blood samples of welders (15.88± 7.11 µg/l) were significantly higher than unexposed workers (9.37± 8.70 µg/l), (P-V<0.05). The frequency of neurobehavioral symptoms of welders was significantly higher compared to unexposed workers (P-V<0.05). The correlation between neurobehavioral symptoms and blood manganese was significant for welders (P-V<0.05).

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Conclusion: Welders’ exposure to manganese and its potential health effects should be evaluated periodically and effective control measures should be applied in order to to prevent neurobehavioral symptoms.

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Introduction: Risk identification and investigation is an appropriate and practical approach for the occupational health professionals. This paper aims to determine exposure to the gases and metal fumes and to perform risk analysis in three common types of welding activities in a shipbuilding industry.
Material and method: This analytical cross-sectional study was conducted in a shipbuilding industry and three types of welding were considered including SMAW, MIG and MAG welding. Sampling of Mn and Cr fumes was carried out using NIOSH 7300 standard method, and NIOSH 6014 method NO2 sampling, and also direct reading devices for CO and O3 gases. Moreover, SQCRA risk assessment method was adopted to specify the level of exposure risk.
Results: The results of risk analysis showed that among gas pollutants, O3 and NO2 in all welding processes had a very high-risk level, while among the metal pollutants; Mn metal showed a high and very high risk level in MIG and SMAW welding.
Conclusion: According to the both sampling results and risk analysis, MIG process welders are more dangerous position than other types of welding.