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Mining industry has one of the highest injury rates among the major industry divisions. Occupational
injuries result in socio-economical consequences for miners, industry as well as for society. Occupational
injuries include accidental injuries and health hazards. In Indian mining industry accidental injuries
is a major concern so far. With increasing mechanization of coal mines, a new dimension needs to be
established in the field of occupational health and safety issues of the miners. In this paper authors
emphasized consequences of dust related diseases, especially Coal Miners Pneumoconiosis and also the
occupational health surveillance of the disease in coal mines for effective elimination of the hazard
with a case study of Singareni Collieries Company Limited (SCCL).
Keywords: Coal miners’ pneumoconiosis, Occupational health, Mechanization, Miner,
Surveillance, SCCL

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  1. 1. Pneumoconiosis and Occupational HealthSurveillance in Coal MinesU. Siva Sankar, V.N.S. Prasad M.* and B. Ramesh KumarSingareni Collieries Company Limited, Kothagudem, Khammam*Corresponding author: E-mail: ABSTRACT Mining industry has one of the highest injury rates among the major industry divisions. Occupational injuries result in socio-economical consequences for miners, industry as well as for society. Occupational injuries include accidental injuries and health hazards. In Indian mining industry accidental injuries is a major concern so far. With increasing mechanization of coal mines, a new dimension needs to be established in the field of occupational health and safety issues of the miners. In this paper authors emphasized consequences of dust related diseases, especially Coal Miners Pneumoconiosis and also the occupational health surveillance of the disease in coal mines for effective elimination of the hazard with a case study of Singareni Collieries Company Limited (SCCL). Keywords: Coal miners’ pneumoconiosis, Occupational health, Mechanization, Miner, Surveillance, SCCLINTRODUCTIONExtraction of minerals from below the surface of the earth is fraught with innumerable dangers. Mininghas been and continues to be a hazardous profession and has a rightly been deemed to be a war with theunpredictable forces of the nature. Coal is one of the world’s most plentiful energy resources, and its use islikely to quadruple by 2020[1]. Coal is dominant source of energy in India and accounts for 55% of thecountry’s energy need. Average daily employment of miners in nearly 570 coalmines lying in differentcoalfields of India is approximately 3.70 lakhs [2]. A focus on the Occupational hazards and overall conditionprevailing in Indian coalmines are felt to be important. Coal is made up of variety of elements. It is mixed with other dusts notably crystalline silica generatedfrom fractured rock in the mine roof or floor of the coal seam which can also become airborne. Coal minedusts can be a significant health risk. When inhaled by miners, dust can result in disease of pulmonarysystem including Coal Miners Pneumoconiosis (CMP), Progressive Massive Fibrosis (PMF), Silicosis, andChronic Obstructive Pulmonary Disease (COPD). The above lung diseases are progressive, disabling, non-reversible and sometimes fatal but preventableoccupational lung disease. Chronic lung diseases, such as CMP were once common in miners, leading toreduced life expectancy. The scientists of Central Mining Research Station (CMRS), Dhanbad (1972) in a survey of 850 coalminers found 19 (2.23%) explicit cases of pneumoconiosis and 54 (6.35%) suspected cases ofpneumoconiosis [3]. In India, official statistics revealed an average of 72 new cases of the disease a year
  2. 2. 814 34th ICSMRI 2011between 1980 and 1994 and sample surveys in India produced estimates as high as 40 per cent of thenumber of miners with CMP [4]. From 1994 to 2010, 141 CMP cases have been notified [5] and thedistribution of cases in SCCL and other coal mines in India is shown graphically in the Figure.1. 45 40 35 SCCL Number of Victims 30 All coal mines-India 25 20 15 10 5 0 94 96 98 00 02 04 06 08 10 19 19 19 20 20 20 20 20 20 Figure 1: Pneumoconiosis cases in India since 1994 In some mining countries black lung is still common, with 4000 new cases of black lung every year inthe USA (4% of miners annually) and 10000 new cases every year in China (0.2% of miners) [6]. The USNational Institute for Occupational Safety and Health (NIOSH) reported that close to 9 percent of minerswith 25 years or more experience tested positive for black lung in 2005 to 2006, compared with 4 percentin the late 1990s [7]. Chest X rays are the only way to confirm CMP, and there is no cure other than a lung transplant [8, 9].Treatments are aimed at the symptoms and complications. The only steps are to remove the patient fromexposure to dust in the early stages to prevent more severe damage. Dealing with the complex health problems arising out of environmental pollution and occupationalhazards requires more aggressive involvement of the medical community[10]. There are very few professionalagencies like National Institute of Occupational health (NIOH) and its arm the Regional OccupationalHealth Centre (ROHC), the National Occupational Health Centre (NOHC), the Industrial ToxicologyResearch Centre (ITRC), Central Labor Institute, National Institute of Miners Health (NIMH), CentralMines Safety and Health Academy functioning at Director General of Mines Safety (DGMS) that are theinstitutes working for the betterment of work-related hazards since independence in India[11,12]. Government of India aimed to significantly reduce the prevalence of Pneumoconiosis/Silicosis by2015 and to totally eliminate Pneumoconiosis/Silicosis at workplaces by 2030 in line with the InternationalLabour Organisation (ILO) and the World Health Organisation’s Global Programme [13].NEWER DIMENSION OF SAFETY AND HEALTH ISSUESThe coal production in India has been increased 16 times from 34.98 Mt in 1951 to 566.13 Mt in 2009-10. ‘Vision Coal 2025’ projected coal production to 1086 Mt by 2024-25 [14]. The reserves amenable toopen cast mining are depleting at a faster rate and environmental concerns are also limiting productionfrom the opencast mines. In order to cope up with future needs, production from open cast and undergroundmines has to be substantially increased using modern and mass production technologies. The present mixof manual, semi mechanized and mechanized mines will have to change in favour of mechanized mines.Technological advancements have made coal mining today more productive than it has ever been.
  3. 3. Pneumoconiosis and Occupational Health Surveillance in Coal Mines 815 In India mining industry has been under going change in terms of technology, size and pattern ofemployment, etc, and the nature of occupational safety and health issues are also expected to change withincrease in mechanization, large scale participation of private entrepreneurs, and outsourcing of differentmining activities. To keep up with technology and to extract coal as efficiently as possible, highly skilledand well trained mining personnel required in the use of complex, state-of-the-art instruments andequipment. Modern mining or mechanisation results in some of the following occupational health andsafety issues; • Modern machines produce lot of heat, noise, dust – making the working environment vulnerable. • Longer hours of work, arduous travel, and musculoskeletal disorders make miners’ life detrimental. • Physiological and mental stress levels in operating modern machines are high, and • Mine safety and health issues largely affected by the socio-economic and socio-political atmosphere prevailing in the mining field. Growth in coal mining is has been phenomenal and complexity in mining has been increased. Butthere has been steady decrease in the trend of mine accidents. Ten yearly average death rate per 1000persons employed has come down from 0.82 in 1951-60 to 0.40 in 2000-10 and number of seriousaccidents has come down from 523 in 1998 to 334 in 2010[12]. The reduction in fatality rate is mainly dueto shift of technology from conventional underground to mechanized opencast mining and also reductionin underground manpower due to introduction of semi mechanization and mechanization.DUST HAZARDS – CMPDust pollution is a predominant problem associated in opencast as well as underground mining operations.The production, transportation and processing of coal generates tiny respirable dust particles that becomeairborne and invisible to the naked eye. Coal or rock dust can range in size from over 100 ìm to < 2 ìm.The miners engaged in mining of minerals are affected with common health hazards due to dust such asCMP, Silicosis, Asbestosis, Siderosis, Berilliyosis. The term “Pneumoconiosis” first coined by pathologist Zenker in 1867, originally meant non-neoplasticfibrotic disease of lung parenchyma, due to inhalation of inorganic/mineral dust. The term has beenbroadened to include diseases due to inhalation of organic dusts [15]. Coal Miners Pneumoconiosis colloquially referred to as ‘Black lung disease’ is the result of infiltrationof coal dust in the lungs of miners work at the coal-face hacking out the coal or elsewhere shifting thelumps of coal or mining waste. Airborne coal dust is composed of inhalable as well as respirable dust.Inhalable dust is the fraction of airborne dust that enters the nose and mouth during breathing, and istherefore available for deposition in the respiratory tract. Respirable dust is the fraction of inhalable dustthat penetrates into the gas exchange region of the lung. It is mostly in the size fraction of 0.1 to 10 µm. As the CMP progresses with continued exposure creates an incurable condition that begins with theinhalation of small coal dust particles. This causes localized reactions, usually in the upper part of thelungs, followed by the formation of fibrous scars. Although asymptomatic in the early stages, as CMPadvances, scarred areas in the lungs increase and coalesce. With massive fibrosis or scarring, pulmonaryfunction decreases, sometimes leads even to death. Prolonged exposure to large amounts of coal dust can result in more serious forms of the disease fromsimple coal workers pneumoconiosis to progressive massive fibrosis (PMF). More commonly, miners exposed todust develop industrial bronchitis, clinically defined as chronic bronchitis (i.e. productive cough for 3months per year for at least 2 years) associated with workplace dust exposure. The incidence of industrialbronchitis varies with age, job, exposure, and habits like smoking etc. In simple CMP, small roundedopacities first appear in the upper lung zones. The opacities may coalesce and form large opacities (>1 cm),characterizing PMF.
  4. 4. 816 34th ICSMRI 2011 Observations on industry workers in Lucknow (India), experiments on rats found that jaggery(a traditional sugar) had a preventive action against the harmful effects of coal dust [16]. In India, Maximum Exposure Limit (MEL) is prescribed as 3 mg/m3 for eight hours time weightedaverage (TWA) provided the concentration of silica content in the respirable dust remains < 5%. In caseSilica % in the respirable dust exceeds 5%, the MEL is calculated to be 15 divided by silica %. It is,therefore essential to determine the % of silica content in the respirable dust in order to define the thresholdlimit (MEL) of the concentration of respirable dust at any work place. There are mainly two standardanalytical methods for determination of crystalline silica content in the dust that are infra redspectrophotometry and X-ray diffraction methods[9,13]. In many countries, the MEL has been prescribed to be 0.3mg/m3 for eight hours TWA. However, inmost of the cases, it is reasonably practicable to control exposure to 0.1 mg/m3 (8 hour TWA) or less byengineering or process control [13].SymptomsThere are several stages of pneumoconiosis. Early stages may go completely unnoticed. Both simple CMPand PMF are often asymptomatic or only affect lung function slightly. When symptoms do occur, shortnessof breath and chronic cough are the most common. Progression to PMF is marked by lung dysfunction,pulmonary hypertension, and cor-pulmoale. Unlike silicosis, patients with CMP do not appear to have asubstantial increased risk for tuberculosis, but coal miners may experience significant silica dust exposure,and therefore the accompanying risks.OCCUPATIONAL HEALTH SURVEILLANCE (OHS)OHS includes Environmental as well as Medical and Biological surveillance.Environmental SurveillanceThis includes monitoring of work environment factors responsible for the diseases.Engineering controlmeasures should be adopted at the work place environment for measurement and reduction of dustgeneration, suppression of dust, proper maintenance of equipment and adopting environmental hygienemeasures.Medical and Biological SurveillanceThis includes monitoring of occurrence of diseases. CMP can be diagnosed with the examination of ChestX-rays only. Symptoms and pulmonary function testing relate to the degree of respiratory impairment, butare not part of the diagnostic criteria. Chest X-rays can detect the early signs of and changes in CMP, oftenbefore the miner is aware of any lung problems. The screening program is only available to current miners[17] . The pre-employment medical examination provides the baseline data for each individual. The periodicalmedical examinations (PME) are conducted for the early detection of CMP. The medical board uses thestandard ILO X-ray plates of pneumoconiosis which is followed all over the world. ILO (2000) classifiedpneumoconiosis for the sake of standardization of the disease fore national and international comparabilityusing 12 point scale of profusion with major categories 0, 1, 2 & 3, which recognize the existence of acontinuity of change from no small opacities to the most advanced category. In India, if the profusion ofany type of pneumoconiotic opacities in chest radiograph is 1/0 or above, the case shall be certified andnotified as pneumoconiosis [18].Patients of category 1 are declared fit for normal duty. Patients of category2 are declared fit for duty away from dust and category 3 and above including PMF are declared unfit forservice in mines. Under Workmen Compensation Act, 1923, compensation ranging from 10% to 100%
  5. 5. Pneumoconiosis and Occupational Health Surveillance in Coal Mines 817depending on the severity of CMP is paid to victims as disease is deemed to be an injury by accident.InIndia, in addition to the statutory provisions on occupational health and hygiene prescribed under MinesAct, coal mines and metal mine regulations, mines rules, and DGMS circulars, National Safety Conferences(NSC) emphasized the creation of occupational health services, occupational health hazards and occupationalhealth surveillance in the mining industry since 7th NSC. Central government notified diseases connectedwith mining operations in the official gazette under section 25(1) of Mines Act, 1952. Silicosis,pneumoconiosis, and asbestosis are dust related diseases notified in coal and non-coal mines. 10th NSC,2007 recommended inclusion of siderosis, and berilliyosis dust related diseases under notified diseases.Prevention of CMPPreventative strategy of CMP can be divided into four levels i.e., Primordial, primary, secondary andtertiary prevention [12].Primordial preventionPrimary prevention entails removal of exposure.Primary preventionThis approach is a critical element of the preventative strategy. It involves prevention of the disease beforeits initiation. It includes introducing dust control measures, the use of appropriate technologies i.e., localexhaust ventilation, process enclosure, wet techniques and substitution to limit exposure to coal dust.Secondary preventionThis is the early detection of the asymptomatic disease and prompt intervention when the disease ispreventable after screening chest X-rays and possibly lung function test. Secondary prevention is importantin determining the efficacy of the dust control measures that are in place and to determine the health risks.Tertiary preventionThis approach is used once the disease has occurred and it aims to lessen the long term impairments anddisability effects stemming from the disease and it entails diagnosis, treatment, appropriate placement,compensation and rehabilitation.A CASE STUDY OF CMP - SCCLIn India, Singareni Collieries Company Limited is pioneered in coal mining technology introduction formeeting the requirements of Southern India. The coal production has been increased ten fold from 5.31Mt in 1973-74 to 51.30 Mt in 2010-11. As on date, the company consists of 67,480 employees engagedin 36 underground mines, 14 opencast mines and in other supporting departments.The trend of certifiedcases of CMP in SCCL from 1965 is presented in graphical form in Figure 2. It is obvious from the Figure2 that during 1965 to 1972 more CMP cases were identified. This was because of engaging miners inmanual mining operations such as drilling, blasting and loading which are the major dusty operations;devoid of dust control measures as well as safety and health precautions. During 1990 there was furtherincrease in CMP cases, which was as a result of commencement of opencast mining operations in 1975and introduction of semi mechanization and mechanization in underground mines after 1978, with lessfocus on occupational health problems. During 2002 to 2010, totally 1,46,393 X-rays were examined as apart of periodical medical examination and in which six persons were found victims of pneumoconiosisand cases fall under the category 1 or less indicating the prevalence is less than 0.009%.
  6. 6. 818 34th ICSMRI 2011 30 25 CMP Cases 20 CWP Cases_SCCL 15 10 5 0 65 67 69 72 74 77 79 81 86 90 92 97 07 09 19 19 19 19 19 19 19 19 19 19 19 19 20 20 Year Figure 2: Trend of Pneumoconiosis cases in SCCL From 1965 to 2010, 131 cases were identified as victims of CMP out of which 126 miners were paidcompensation ranging from 10% to 100%. As per the medical records, none of the PMF cases wereobserved so far. From the observation of the past data, it is found that miner is prone to pneumoconiosisafter 12 years of exposure to respirable dust at workplace environment. There is 100% reduction in the cases from the year 1965 to 2010. In the last 30 years, there was onlyone year which recorded more than 5 CMP cases. This was achieved with stringent application ofengineering, medical and statutory controls and organization’s commitment towards occupational healthand safety of miners.Measures Taken by SCCLVarious measures have been taken in opencast and underground mines of SCCL, to prevent liberationaccumulation and propagation of airborne dust with a view to completely eliminate pneumoconiosis incoal mines. These include management, engineering, medical and statutory control measures. For instancesome of the observed measures are as given below; • Except few mines manual loading operations are completely eliminated in underground mines with the introduction of side discharge loaders; load haul dumpers; roadheaders; and continuous miner and longwall technologies. • Improved ventilation in terms of both quantity and velocity to reduce airborne dust concentration at working places of underground mines. • Wet drilling for roof bolting, water sprinkling at transfer points of belts, stage loader, crusher, feeder breaker and enclosing with belts wherever possible in underground mines. • Remote control operation of load haul dumpers, continuous miners and using uni-directional cutting sequence in longwall to prevent operator’s exposure to air borne respirable dust. • Inbuilt dust scrubbers with continuous miners, exhaust ventilation with dust filters in roadheader faces is provided besides drum mounted water spraying system on roadheaders, continuous miners and shearers. • Proper maintenance and cleaning of belts, cutting machinery and replacement of cutting tools in due course. • Mist sprays provided at coal transfer and unloading points; solenoid activated water spraying on belts; fully enclosed crushing plants; pre weigh bins and silos in coal handling plants and mast mounted high capacity water sprinklers at coal yards. • Wet drilling and dry drilling equipped with dust collectors for drilling blast holes; cleaning of pavements; water sprinkling on haul roads, and plantation in and around open cast mines.
  7. 7. Pneumoconiosis and Occupational Health Surveillance in Coal Mines 819 • Conducting ambient air quality measurements with the help of high volume samplers at 241 strategic locations on every fortnight to detect Suspended Particulate Matter (SPM), Respirable Particulate Matter (RPM), SO2, NOx etc., in all mining areas. • When profusion of pneumoconiosis in chest X-ray is more than 0/1, miner is kept under medical surveillance and shifted to less dust area to prevent further development of CMP. • Evaluation of dust control measures in mines where CMP case(s) is/are identified. • As per NSC recommendations, modern diagnostic equipments have been provided in PME centers of all mining areas in order to detect the occupational health diseases at the earliest during medical examinations. • Occupational disease board was constituted in 2006 after 9th NSC recommendation as a part of occupational health surveillance of miners. • Education of the miners on sanitation, cleanliness, hygiene, and health care and conducting mobile health programs at regular intervals. • Safety committee members and workmen inspectors examine dust measurements; engineering dust controls and dust records at regular intervals with active participation.CONCLUSIONSCoal mining in India is at a very critical juncture; increasing mechanization and privatization pose a greatchallenge on occupational health and safety issues of mining industry. The accident figures which appearin government statistics do not reveal the actual situation and the figures say almost nothing about theoccupational diseases in the mines due to less attentiveness on occupational health so far. SCCL has been striving for meeting coal demand in southern India, and aimed at continuousintroduction of modern mining with a spotlight on occupation health and safety of its miners. SCCL isalways vanguard in taking measures to completely eliminate dust related diseases as well as in the concernof occupational health and safety of miners when compared to other counterparts in India. • Last but not least let us remember the famous quotation of Albert Einstein “Concern for man and his fate must always form the chief interest of all technical endeavors. Never forget this in the midst of your diagrams and equations”. Steps necessary for improving conditions of occupational health and safety status in coal mines include; • Strengthened organization and appropriate leadership in trade unions, conscious miners, who are able to control the work process, and the generation of unbiased information about occupational hazards are essential. • Every organisation should have occupational health policy and formulate a comprehensive surveillance programme suitable to its specific occupational health problems for prevention of occupational diseases. • Inculcating better system and work culture by adopting ISO certification schemes for Quality, Environment, Occupational Health and Safety and Risk Management; (Viz; ISO 9000, ISO 14000, OHSAS 18000 & ISO 27000 ) for the total system from extraction to utilization. • The periodical medical examination of miners and dust measurements need to be integrated and pursued together so that the benefits of the dust control measures can be appraised in terms of change in morbidity. • Work should be allotted depending upon the two principles, which are, ‘Miner fit for job’ and ‘fit the job for Miner’. • DGMS should start ‘Mobile Health Screening Program’ to carry out health evaluations of the miners independently at regular intervals.
  8. 8. 820 34th ICSMRI 2011 • Active participation of professional agencies of medical community is required for dealing with occupational health hazards of miners.ACKNOWLEDGEMENTSThe Authors expressed their profound gratitude to the Dr. K. Prasanna Simha, CMO, Dr. M.N. RamaKrishna, Dy. CMO and Dr. B.S.S.V. Prasada Rao, Medical Supdt., SCCL for providing the necessary dataand guidance. The views expressed by the authors are of their own and not the organization which theybelong.REFERENCES“Black lung on the rise among US coal miners”. World Socialist Web Site. January 11, 2010. 2010/jan2010/blac-j11.shtml.Central Mining Research Station, Dhanbad, 1971-1972, Annual Report-Study of Dust Problem in a Coal Mine, pp.119-120.Chatterjee, S.K.,1976. “Pneumoconiosis” Ind. J. Tub., Vol. XXV, No. 1. (From National Institute of Occupational Health, Ahmedabad).DGMS, “DGMS (Tech) (S&T) Circular No.01, 2010”, GOI, Ministry of Labour & Employment, Directorate General of Mines Safety, 10th March, 2011.DGMS, “Standard note 2010”, Ministry of Labour & Employment, Directorate General of Mines Safety. , 10th March, 2011.DGMS,—ed.../wcms_150296.pdf., 21st March, 2011. briefings/fossil_fuel_disasters.php, 23rd March, 2011.DGMS,”DGMS Strategic Plan 2011-15", Ministry of Labour & Employment, Directorate General of Mines Safety.: Pg 10-11, 49,, 10th March, 2011.Jay F. Colinet et al, 2010, “Best Practices for Dust Control in Coal Mining” IC 9517 Information Circular/2010, pp. 8, 12.Joshi,T.K.,2011. “Practising Occupational Health In India “Ch_ 16 - Practising Occupational Health in India.mht,, 2nd March, 2011.L.C.Kaku, “DGMS Circulars-2004”, National safety Conference Recommendations, pp. 662, Lovely Prakashan, India.Labour issues: “Mining: blood on coal” Vol. 18 - Issue 13, 23rd Jun – 06th Jul. 06, 2001, India’s National Magazine from the publishers of THE HINDU.,, 10th March, 2011.Mandal, K.A., 2009. “Strategies and policies deteriorate occupational health situation in India: A review based on social determinant framework”; Indian J Occup Environ Med. 13th December;2009 13(3), pp.113–120.NIOSH,”Enhanced Coal Workers’ Health Surveillance Program”. National Institute for Occupational Safety and Health. 12th November , 2008., Anand P, Saxena, Ashok K., 1994. “Enhanced Translocation of Particles from Lungs by Jaggery”. Environmental Health Perspectives (Brogan &#38) 102 (S5), pp.211–214. doi:10.2307/3432088. PMID 7882934. 1567304. 5/sahu-full.html.Singh, A. K., 2010. “Growth perspective of coal sector in India”, Vol.1, Pg 75, 3rd Asian Mining Congress, 22 - 25 January 2010, Kolkata, India, The Mining, Geological and Metallurgical Institute of India (MGMI).Stephanie Joyce Major Issues in Miner Health Environmental Health Perspectives Volume 106, Number 11, November 1998.World Bank, Coal mining and Production, pollution prevention and abatement hand book, World Bank Group, 1998., 18th March, 2011.