To cite this article: Bibhuti B. Mandal & Neil J. Mansfield (2016) Contribution of individual com... more To cite this article: Bibhuti B. Mandal & Neil J. Mansfield (2016) Contribution of individual components of a job cycle on overall severity of whole-body vibration exposure: a study in Drivers of earth-moving machines are exposed to whole-body vibration (WBV). In mining operations there can be a combination of relatively high magnitudes of vibration and long exposure times. Effective risk mitigation requires understanding of the main aspects of a task that pose a hazard to health. There are very few published studies of WBV exposure from India. This paper reports on a study that considered the contribution of the component phases of dumper operations, on the overall vibration exposure of the drivers. It shows that vibration magnitudes are relatively high, and that haulage tasks are the main contributor to the exposure. It is recommended that driver speed, haul road surfaces and vehicle maintenance/selection are optimized to ensure minimization of vibration. If this is not sufficient, operation times might need to be reduced in order to ensure that the health guidance caution zone from Standard No. ISO 2631-1:1997 is not exceeded.
Background: Noise mapping being an established practice in Europe is hardly practiced for noise m... more Background: Noise mapping being an established practice in Europe is hardly practiced for noise management in India although it is mandatory in Indian mines as per guidelines of the Directorate General of Mines Safety (DGMS). As a pilot study, noise mapping was conducted in an opencast mine with three different models; one based on the baseline operating conditions in two shifts (Situation A), and two other virtual situations where either production targets were enhanced by extending working hours to three shifts (Situation B) or only by increased mechanization and not changing the duration of work (Situation C). Methods: Noise sources were categorized as point, line, area, and moving sources. Considering measured power of the sources, specific meteorological and geographical parameters, noise maps were generated using Predictor LimA software. Results: In all three situations, L den values were 95 dB(A) and 70–80 dB(A) near drill machine and haul roads, respectively. Noise contours were wider in Situation C due to increase in frequency of dumpers. L den values near Shovel 1 and Shovel 2 under Situation B increased by 5 dB and 3 dB, respectively due to expansion of working hours. In Situation C, noise levels were >82 dB(A) around shovels. Noise levels on both sides of conveyor belts were in the range of 80–85 dB(A) in Situations A and C whereas it was 85–90 dB(A) in Situation B. Near crusher plants, it ranged from 80 to 90 dB(A) in Situations A and C and between 85 and 95 dB(A) in Situation B. In all situations, noise levels near residential areas exceeded the Central Pollution Control Board (CPCB) limits, i.e., 55 dB(A). Conclusions: For all situations, predicted noise levels exceeded CPCB limits within the mine and nearby residential area. Residential areas near the crusher plants are vulnerable to increased noise propagation. It is recommended to put an acoustic barrier near the crusher plant to attenuate the noise propagation.
Mandal, B. B. and Srivastava, A. K. (2006) ‘Mechanisation, vibration and the Indian workforce’, Asian Pacific Newsletter on occupational safety and health, 13(2), pp. 38-40., 2006
Mandal, B. B. and Srivastava, A. K. (2010) ‘Musculoskeletal disorders among the dumper operators exposed to whole body vibration in Indian mines’, International Journal of Mining Reclamation and Environment, 24(3), pp. 233-243., 2010
Dumper operators are exposed to whole body vibration (WBV) in the course of their work. The expos... more Dumper operators are exposed to whole body vibration (WBV) in the course of their work. The exposure to WBV in a coal mine in Central India was investigated through measurement of the magnitude of vibration and exposure time. The vibration magnitude along the dominant Z-axis ranged from 0.644 to 1.82 m/s2 in terms of root mean square acceleration. When evaluated in conjunction with their average daily exposure time of 5 h, all dumpers caused elevated health risk for their operators according to guidelines in ISO 2631-1:1997 WBV standard. Health risks were re-affirmed when vibration dose value (VDV) was applied as an additional tool for risk assessment. Forty dumper operators and 20 controls from the same mine were selected for detailed studies. The control population was not exposed to WBV. An epidemiological study was carried out to determine the prevalence of musculoskeletal disorders (MSD) related to WBV exposure. It was observed that the problem of low back pain was significantly higher (85%) in the exposed population as compared to controls (20%). Similarly, pain in the ankle (37.83%), shoulder (30%) and neck (37.5%) was higher among exposed personnel as compared to the control population (5, 0 and 15%, respectively). A significant degradation in quality of life among the exposed subjects was also observed.
Mandal, B. B., Sarkar, K. and Manwar, V. (2012) ‘A study of vibration exposure and work practices of Loader and Dozer operators in opencast mines’, International Journal of Occupational Safety and Health, 2 (2), pp. 3-7., 2012
Background: Exposure to whole body vibration (WBV) at work and development of musculoskeletal dis... more Background: Exposure to whole body vibration (WBV) at work and development of musculoskeletal disorders are well linked. Vehicle vibrations are usually perceived to occur in vertical direction and are likely to cause lumbar disorders in operators. Vibration characteristics of the machines need to be studied and compared with work practices which may indicate nature of health risk to operators. This may help in developing specific action plans to control vibration related health risk.
Objective: The objectives of the study were, to measure and analyze vibration magnitudes, observe work practices of Loaders and Dozers, evaluate health risk to their operators and to formulate recommendations for control measures.
Methods and Material: Frequency weighted Root Mean Square values of acceleration data was collected as per guidelines in ISO 2631-1:1997 using human vibration analyzers. WBV exposure of 40 (Forty) Loader and Dozer operators in eight opencast mines were evaluated to assess health risk using vibration magnitude and corresponding daily exposure durations.
Results and Conclusion: The dominant axis of vibration in dozers was found to be X (front to back) in 80% of the equipments. This is different from transporting equipment like Dumpers which have Z axis as dominant axis of vibration. A continuous change of movement in forward and reverse direction and rash driving were found to be contributory factors for increased vibration intensity along X- axis. It was observed that 27(68%) of them showed moderate whereas 12(30%) equipment showed high health risk. It is suggested that vibration control measures should be designed and adopted based not only on the intensity but also on the dominant axis typical to the equipment and work practices.
Keywords: whole body vibration; mine hazards; environmental health; occupational health; work practice; mining machinery
Mandal, B. B., Pal, A. K. and Sishodiya, P. K. (2013) ‘Vibration characteristics of mining equipment used in Indian mines and their vibration hazard potential’, International Journal of Environmental Health Engineering, 2(4), pp. 14-22., 2013
Mandal, B. B., Bhattacharya, S., A, Anupam. and Jain, P. K. (2014) ‘Vibration exposure of workmen of coal preparation plants - an exploratory study’, Noise and Vibration Worldwide. July 2017:45(7), 21-31, 2014
To cite this article: Bibhuti B. Mandal & Neil J. Mansfield (2016) Contribution of individual com... more To cite this article: Bibhuti B. Mandal & Neil J. Mansfield (2016) Contribution of individual components of a job cycle on overall severity of whole-body vibration exposure: a study in Drivers of earth-moving machines are exposed to whole-body vibration (WBV). In mining operations there can be a combination of relatively high magnitudes of vibration and long exposure times. Effective risk mitigation requires understanding of the main aspects of a task that pose a hazard to health. There are very few published studies of WBV exposure from India. This paper reports on a study that considered the contribution of the component phases of dumper operations, on the overall vibration exposure of the drivers. It shows that vibration magnitudes are relatively high, and that haulage tasks are the main contributor to the exposure. It is recommended that driver speed, haul road surfaces and vehicle maintenance/selection are optimized to ensure minimization of vibration. If this is not sufficient, operation times might need to be reduced in order to ensure that the health guidance caution zone from Standard No. ISO 2631-1:1997 is not exceeded.
Background: Noise mapping being an established practice in Europe is hardly practiced for noise m... more Background: Noise mapping being an established practice in Europe is hardly practiced for noise management in India although it is mandatory in Indian mines as per guidelines of the Directorate General of Mines Safety (DGMS). As a pilot study, noise mapping was conducted in an opencast mine with three different models; one based on the baseline operating conditions in two shifts (Situation A), and two other virtual situations where either production targets were enhanced by extending working hours to three shifts (Situation B) or only by increased mechanization and not changing the duration of work (Situation C). Methods: Noise sources were categorized as point, line, area, and moving sources. Considering measured power of the sources, specific meteorological and geographical parameters, noise maps were generated using Predictor LimA software. Results: In all three situations, L den values were 95 dB(A) and 70–80 dB(A) near drill machine and haul roads, respectively. Noise contours were wider in Situation C due to increase in frequency of dumpers. L den values near Shovel 1 and Shovel 2 under Situation B increased by 5 dB and 3 dB, respectively due to expansion of working hours. In Situation C, noise levels were >82 dB(A) around shovels. Noise levels on both sides of conveyor belts were in the range of 80–85 dB(A) in Situations A and C whereas it was 85–90 dB(A) in Situation B. Near crusher plants, it ranged from 80 to 90 dB(A) in Situations A and C and between 85 and 95 dB(A) in Situation B. In all situations, noise levels near residential areas exceeded the Central Pollution Control Board (CPCB) limits, i.e., 55 dB(A). Conclusions: For all situations, predicted noise levels exceeded CPCB limits within the mine and nearby residential area. Residential areas near the crusher plants are vulnerable to increased noise propagation. It is recommended to put an acoustic barrier near the crusher plant to attenuate the noise propagation.
Mandal, B. B. and Srivastava, A. K. (2006) ‘Mechanisation, vibration and the Indian workforce’, Asian Pacific Newsletter on occupational safety and health, 13(2), pp. 38-40., 2006
Mandal, B. B. and Srivastava, A. K. (2010) ‘Musculoskeletal disorders among the dumper operators exposed to whole body vibration in Indian mines’, International Journal of Mining Reclamation and Environment, 24(3), pp. 233-243., 2010
Dumper operators are exposed to whole body vibration (WBV) in the course of their work. The expos... more Dumper operators are exposed to whole body vibration (WBV) in the course of their work. The exposure to WBV in a coal mine in Central India was investigated through measurement of the magnitude of vibration and exposure time. The vibration magnitude along the dominant Z-axis ranged from 0.644 to 1.82 m/s2 in terms of root mean square acceleration. When evaluated in conjunction with their average daily exposure time of 5 h, all dumpers caused elevated health risk for their operators according to guidelines in ISO 2631-1:1997 WBV standard. Health risks were re-affirmed when vibration dose value (VDV) was applied as an additional tool for risk assessment. Forty dumper operators and 20 controls from the same mine were selected for detailed studies. The control population was not exposed to WBV. An epidemiological study was carried out to determine the prevalence of musculoskeletal disorders (MSD) related to WBV exposure. It was observed that the problem of low back pain was significantly higher (85%) in the exposed population as compared to controls (20%). Similarly, pain in the ankle (37.83%), shoulder (30%) and neck (37.5%) was higher among exposed personnel as compared to the control population (5, 0 and 15%, respectively). A significant degradation in quality of life among the exposed subjects was also observed.
Mandal, B. B., Sarkar, K. and Manwar, V. (2012) ‘A study of vibration exposure and work practices of Loader and Dozer operators in opencast mines’, International Journal of Occupational Safety and Health, 2 (2), pp. 3-7., 2012
Background: Exposure to whole body vibration (WBV) at work and development of musculoskeletal dis... more Background: Exposure to whole body vibration (WBV) at work and development of musculoskeletal disorders are well linked. Vehicle vibrations are usually perceived to occur in vertical direction and are likely to cause lumbar disorders in operators. Vibration characteristics of the machines need to be studied and compared with work practices which may indicate nature of health risk to operators. This may help in developing specific action plans to control vibration related health risk.
Objective: The objectives of the study were, to measure and analyze vibration magnitudes, observe work practices of Loaders and Dozers, evaluate health risk to their operators and to formulate recommendations for control measures.
Methods and Material: Frequency weighted Root Mean Square values of acceleration data was collected as per guidelines in ISO 2631-1:1997 using human vibration analyzers. WBV exposure of 40 (Forty) Loader and Dozer operators in eight opencast mines were evaluated to assess health risk using vibration magnitude and corresponding daily exposure durations.
Results and Conclusion: The dominant axis of vibration in dozers was found to be X (front to back) in 80% of the equipments. This is different from transporting equipment like Dumpers which have Z axis as dominant axis of vibration. A continuous change of movement in forward and reverse direction and rash driving were found to be contributory factors for increased vibration intensity along X- axis. It was observed that 27(68%) of them showed moderate whereas 12(30%) equipment showed high health risk. It is suggested that vibration control measures should be designed and adopted based not only on the intensity but also on the dominant axis typical to the equipment and work practices.
Keywords: whole body vibration; mine hazards; environmental health; occupational health; work practice; mining machinery
Mandal, B. B., Pal, A. K. and Sishodiya, P. K. (2013) ‘Vibration characteristics of mining equipment used in Indian mines and their vibration hazard potential’, International Journal of Environmental Health Engineering, 2(4), pp. 14-22., 2013
Mandal, B. B., Bhattacharya, S., A, Anupam. and Jain, P. K. (2014) ‘Vibration exposure of workmen of coal preparation plants - an exploratory study’, Noise and Vibration Worldwide. July 2017:45(7), 21-31, 2014
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Papers by Dr. B B Mandal
Objective: The objectives of the study were, to measure and analyze vibration magnitudes, observe work practices of Loaders and Dozers, evaluate health risk to their operators and to formulate recommendations for control measures.
Methods and Material: Frequency weighted Root Mean Square values of acceleration data was collected as per guidelines in ISO 2631-1:1997 using human vibration analyzers. WBV exposure of 40 (Forty) Loader and Dozer operators in eight opencast mines were evaluated to assess health risk using vibration magnitude and corresponding daily exposure durations.
Results and Conclusion: The dominant axis of vibration in dozers was found to be X (front to back) in 80% of the equipments. This is different from transporting equipment like Dumpers which have Z axis as dominant axis of vibration. A continuous change of movement in forward and reverse direction and rash driving were found to be contributory factors for increased vibration intensity along X- axis. It was observed that 27(68%) of them showed moderate whereas 12(30%) equipment showed high health risk. It is suggested that vibration control measures should be designed and adopted based not only on the intensity but also on the dominant axis typical to the equipment and work practices.
Keywords: whole body vibration; mine hazards; environmental health; occupational health; work practice; mining machinery
Objective: The objectives of the study were, to measure and analyze vibration magnitudes, observe work practices of Loaders and Dozers, evaluate health risk to their operators and to formulate recommendations for control measures.
Methods and Material: Frequency weighted Root Mean Square values of acceleration data was collected as per guidelines in ISO 2631-1:1997 using human vibration analyzers. WBV exposure of 40 (Forty) Loader and Dozer operators in eight opencast mines were evaluated to assess health risk using vibration magnitude and corresponding daily exposure durations.
Results and Conclusion: The dominant axis of vibration in dozers was found to be X (front to back) in 80% of the equipments. This is different from transporting equipment like Dumpers which have Z axis as dominant axis of vibration. A continuous change of movement in forward and reverse direction and rash driving were found to be contributory factors for increased vibration intensity along X- axis. It was observed that 27(68%) of them showed moderate whereas 12(30%) equipment showed high health risk. It is suggested that vibration control measures should be designed and adopted based not only on the intensity but also on the dominant axis typical to the equipment and work practices.
Keywords: whole body vibration; mine hazards; environmental health; occupational health; work practice; mining machinery