Underground Worker Research Articles

ON THE ISSUE OF RADON EXPOSURE IN THE EXISTING RADIATION SITUATION AT WORKPLACES.

assessment of probable exposure levels from radon and NORM in workplaces within the context of justi fying radiation protection plans in an existing exposure situation. Materials regarding the assessment of naturally occurring radioactive material (NORM) con tent in tailing from mining and processing industries in Ukraine and assessments of contamination levels of industri al sites of oil and gas enterprises were used for estimating the probable range of effective doses (ED) of workers fromNORM at industrial enterprises. These materials were obtained as a result of research conducted by specialists from theRadiation Protection Laboratory of the State Institution «O.M. Marzіeiev Institute for Public Health of the NationalAcademy of Medical Sciences of Ukraine» (RP SI «IPH NAMSU»). The results of studies conducted by the StateInstitution «Ukrainian Scientific Research Institute of Industrial Medicine» (SI «UKRMEDPROM») were used for calcu lating the EDs of iron ore miners. Calculations of probable EDs of industrial enterprise workers were carried out usingmethodologies and recommendations from publications of the IAEA related to occupational exposure. Assessments ofexposure levels for office workers were based on measurements of indoor radon concentrations of first-floor premisesin multi-story buildings of industrial urban development from the laboratory's own databases. Radon measurements inindoor air were conducted using passive track etch radon detectors with an exposure time of at least 30 days.Calculations of EDs for office workers were carried out using dose coefficients and mathematical models from the ICRP. When workers are exposed to radon as a result of the technological process, radiation exposure is limitedby dose criteria. Using non-uranium miners as an example, it was shown that effective doses (ED) due to gammaradiation varied within a narrow range, ranging from 0.2 to 0.4 mSv/year, and were on average an order of magnitudelower than the radon component of the total ED for the two groups of mines, which amounted to 2.0-14.0 mSv/yearfor the Northern group and 0.3-0.8 mSv/year for the Southern group. For three underground worker specialties, radi ation EDs could potentially exceed the reference level of 6 mSv/year and fall under regulatory control. Potentialradiation EDs for workers at one of the Ukrainian oil fields were generally not significant (<0.1-1 mSv/year), exceptfor areas where used pipe storage and sludge settlers were located (70.0 mSv/year; 28.0 mSv/year at a distance of10 meters), near which dose limits for Category A personnel (6 mSv/year), falling under regulatory control, wereexceeded. Radon exposure in workplaces also includes the presence of workers in regular office premises on the firstfloors of multi-story buildings, where the main source of radon entry into the air is the underlying soil. For the mostresearched regions of Ukraine (~1200 measurements of radon activity concentrations in first-floor premises), it wasfound that the reference level of 300 Bq/m3 is exceeded in 0.2-0.5% of cases in certain regions, indicating thatpotentially the reference level may be exceeded in tens of thousands of premises. A differentiated approach is justified for assessing the hazards of workplaces, allowing for optimizingradiation protection for workers at a reasonable cost and saving significant resources for enterprises. Effective doses(ED) of radiation for workers at enterprises where radon is an integral part of the technological process vary widelyand can differ by an order of magnitude even within the same enterprise. Reference levels of 300 Bq/m3 may beexceeded in tens of thousands of office premises, and only through direct measurements of radon activity concen trations in building air can such premises be identified.

Administrative Burden of the Compensation Claim System - Physicians and Union Compensation Representatives’ Views

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, causing 3.23 million deaths in 2019. Cigarettes are the leading cause of this disease. However, workplace exposures, including those in the mining industry, may also lead to COPD. These exposures include dust and fumes that can be higher for mineral industry workers who work in confined areas. As a result, workers in the minerals industry may submit compensation claims. Sadly, work-related COPD is not well compensated or recognized by the Ontario Workplace Safety and Insurance Board (WSIB). Physicians and union representatives struggle to complete forms and have claims approved, and because of this, workers can struggle with money, family, and mental health problems. This qualitative narrative study used in-depth telephone interviews (eight) to collect information. The information collected from physicians (four) and union representatives (four) was analyzed to understand their perspectives and experiences when assisting workers with compensation claims. This is the first study to examine how COPD could affect underground mineral workers in Northeastern Ontario. Themes identified in this study include 1) additional administrative and human support resources are required, 2) smoking cessation is essential, 3) COPD is a crippling disease, 4) education is required to support documenting an occupational illness, 5) the compensation claim process is challenging; 6) occupational diseases are challenging to prove, 7) occupational COPD is costly. This study may help with compensation services and provide support for physicians and union representatives involved with an underground mineral worker diagnosed with occupational COPD.

A case of pulmonary aspergillus infection in underground coal mine workers

The underground environment is dark and humid, and it is easy to breed pathogenic microorganisms. A lump in the right lung of a coal mine underground transport worker was found druing occupational health examination. CT examination showed that the lump was located in the posterior segment of the upper lobe of the right lung, with point strip calcification, liquefaction necrosis, and proximal bronchial stenosis and occlusion. MRI examination FS-T(2)WI and DWI showed "target sign", annular low signal around the central high signal, and low mixed signal around the periphery, and annular high signal in the isosignal lesions on T(1)WI. Then the pulmonary aspergillus infection was confirmed by pathology.

РОЗРОБКА ТА МОДЕЛЮВАННЯ АЛГОРИТМУ ПРИЙНЯТТЯ РІШЕНЬ ЩОДО КРИТИЧНОГО СТАНУ ЗДОРОВ’Я ПІДЗЕМНИХ ПРАЦІВНИКІВ ВУГІЛЬНИХ ШАХТ

Purpose. Improving the effectiveness of management decisions regarding the safety of underground coal mine workers by developing an algorithm for making decisions about the critical health condition of a miner. Results. The work solves the complex task of developing and modeling a decision-making algorithm about the state of health and individual vital indicators of miners in real time: the list of indicators for monitoring is substantiated and their levels have been ranked; technical means of monitoring have been selected; fuzzy logic rules and an algorithm for making a decision about the criticality of an underground worker's health have been developed; simulation of the algorithm has been performed. The proposed algorithm allows real-time tracking of the location of miners and provides individual information on indicators of their physical condition, such as body temperature, pulse and blood pressure. This provides an opportunity to quickly respond to potentially dangerous situations and act appropriately. Scientific novelty. The novelty of the work consists in the development of an algorithm that combines the monitoring of the location and individual vital signs of miners and decision-making about their physical condition. Practical importance. The approaches proposed in the work can be implemented in the existing operational and dispatching control systems of coal enterprises and allow monitoring the emergence of critical health conditions of workers.

IoT Based Underground Worker Safety System

Abstract: Industrial safety is one of the main aspects of industry specially coal mine industry. Underground mining hazards include suffocation, gas poisoning and gas explosion. Air quality and hazardous event detection is very important factor in mining industry. This system provides a wireless sensor network for monitoring real time situation of underground mines from base station. It provides real time monitoring of harmful gases like CO, CH4 and also temperature and Humidity. The main reason for death of miners is that, due to any reason miners falls down and loses consciousness also proper treatment is not provided them at that time. To overcome this problem the system provides emergency alert to the supervisor if person fall down by any reason. The system uses IoT technology for transmission of data from underground mine to base station. There is alert switch at mines and base station for emergency purpose.

СТРУКТУРА ТА ФУНКЦІОНАЛ АВТОМАТИЗОВАНОЇ ПІДСИСТЕМИ МОНІТОРИНГУ ТА КОНТРОЛЮ ТЕХНОЛОГІЧНИХ ПОКАЗНИКІВ ВИДОБУВНИХ ЗАБОЇВ ВУГІЛЬНИХ ШАХТ

underground works by providing operator control of technological processes, systems for collecting, processing and archiving information about the object. Ability to monitor vital signs and determine the location of a particular miner in real time. Methods. The communication systems used today in the coal industry have come a long way since their development. Most mines use outdated communication systems between a dispatcher and miners. Working safely in the coal industry is extremely important. The requirements for the control of data collection for observation, monitoring and exchange of information in real time should grow with the improvement of the technical capabilities of positioning systems and move to a higher level of control of individual health parameters. Results. The article analyzes the used systems and methods of positioning miners. The advantages and disadvantages of the existing systems for monitoring the technological indicators of coal mines, the optimal technology of data transmission and determining the location of an underground worker have been established. The directions of further research on improving the control of vital activity indicators, the possibility of prompt transmission of a signal to the dispatcher in the event of an emergency, and individual personalization of the miner based on RFID technologies have been determined. The practical value of the obtained results lies in the functional addition of the used systems, which allows timely and highly accurate rescue blocked miners with the possibility of tracking their condition indicators. Scientific novelty. The article offers a new functionality and structure of an automated subsystem for monitoring and controlling the technological indicators of mining pits of coal mines, which differ from the existing personal monitoring of vital indicators of workers in real time due to the use of active RFID tags embedded in separate devices. Practical importance. Improving the safety of underground works.

Underground Gold Miner Exposure to Noise, Diesel Particulate Matter and Crystalline Silica Dust.

Background.Respirable dust, diesel particulate matter, crystalline silica and noise pollution are the most common causes of health issues experienced by underground mine workers. Assessment of exposure levels in relation to standard regulatory body permissible levels is essential for the safety of mine workers.Objectives.The present study compared exposure levels of diesel particulate matter, crystalline silica dust and noise experienced across different underground mine worker job titles.Methods.Subjective sampling was employed using gravimetric air samplers over an 8-hour time weighted average for two periods designated as period 1 (first half of the year) and period 2 (second half of the year). A comparative analysis of exposure levels between job titles and in relation to the National Institute for Occupational Safety and Health (NIOSH) permissible exposure levels (PELs) was performed.Results.In the present study, 90% of the selected job titles were over-exposed to noise and 80% were over-exposed to diesel particulate matter. The highest exposures for crystalline silica dust and diesel particulate matter were found in the 40–49-year-old age group.Conclusions.The present study of exposure levels of diesel particulate matter, respirable dust, crystalline silica, and noise during underground gold mining demonstrates that better control mechanisms are needed to protect workers.Participant Consent.ObtainedEthics Approval.This study was approved by the Ethics Committee of the Kwame Nkrumah University of Science and Technology, Ghana.Competing Interests.The authors declare no competing financial interests.

ОЦІНКА ТЕХНІЧНО ДОСЯЖНОГО РІВНЯ ЗАПИЛЕНОСТІ ПОВІТРЯ ПРИ ВИЇМКОВИХ РОБОТАХ У ВУГІЛЬНИХ ШАХТАХ

Purpose. Development of a criterion for compliance with the normative indicator – technically achievable level of dust (TAL) – a safe dose of dust particles that have entered the lungs of the employee for the entire period of retirement. Method. The research was conducted on the basis of standard algebraic analysis of the requirements of regulatory documents. Results. A criterion was obtained for the assessment by the coordinating organizations of the correctness of the mine’s determination of the technically achievable level of dustiness of the TAL. It is not related to the assessment of the perfection of dust control technology, but to the medical requirements for the prevention of employee pneumoconiosis during the entire retirement age of his work in a dusty atmosphere (20 years). The criterion is based on the amount of dust load on the respiratory organs of the underground worker during the shift, month, year and the entire period of his work, regulated by current regulations. Scientific novelty. It consists in the mathematical formalization of an intuitive connection between TAL – the maximum level of dustiness of underground workings during excavation machines, medium-variable dust, which takes into account interruptions in the work of excavation machines, and dust load on the respiratory organs of the worker. Practical meaning. The developed criterion allows to carry out the coordinated policy of the management and trade unions of the coal enterprises, supervisory and coordinating instances in questions of reasonable sufficiency of the planned antidust measures, both at a stage of drawing up of the design documentation, and at coordination of acts of TAL. Key words: dustiness, dust load, respiratory organs, dust excretion, dust suppression.

REASSESSMENT OF RADIATION EXPOSURES OF UNDERGROUND NON-URANIUM MINE WORKERS IN WESTERN AUSTRALIA

In the 1990, radon and radon progeny was reported to contribute approximately 70% of the average 1.4+1.0-mSv annual dose across 26 Western Australian underground non-uranium mines. The Western Australian underground mining workforce has expanded significantly, and parameters used to calculate doses have changed significantly, warranting a review of the 1990's data. The review concludes that doses received by the contemporary mining workforce has increased on average, by 5.4%, with annual dose estimates ranging from 0.53 to 3.56mSv, with a mean of 1.33mSv. Doses in 12 of the 23 underground mines exceed 1mSv and are required to comply with radiation safety legislation. It is estimated that 5400 underground workers will fall into the greater than 1-mSv category. The collective dose to the underground worker population has increased by 4.5 times from 3060 man mSv (2173 workers) to 13 669 man mSv (8597 workers).

Analysis of the motivational nature of remuneration in the light of production and efficiency in hard coal mining in Poland

In the course of management, three basic resources are used: material, financial and human resources. However, the last of the above resources - employees, is a demographic and unpredictable resource that rarely performs what is required by the employer or supervisor, loyally and with appropriate commitment. Therefore, effective methods of motivating employees are needed, and in mining enterprises with a small range of other incentives, the most common incentive should be a financial factor. For this to happen a remuneration structure should include, among others, a variable bonus based on the work results obtained by an employee or related to the effects of the entire enterprise. With rational rules for its allocation, it can be one of the key elements of improving production efficiency in mining enterprises. Well-designed remuneration should stimulate employees to work and develop. Analysing the structure of an average wage of a physical underground worker in a randomly selected mining company in Silesia, such pro-effective structures have not been found, which is a very unfavourable situation. In addition, in the search for the incentive nature of these wages, the changes in their amount have been analysed in the light of changes in the volume of hard coal production and labour productivity in hard coal mining in Poland.

Love and Danger on the Underground Railroad: George and Edy Duncan’s Journey to Freedom, 1820

Love and Danger on the Underground RailroadGeorge and Edy Duncan’s Journey to Freedom, 1820 Roy E. Finkenbine (bio) In 1820 fugitives from slavery in the American South began showing up for the first time at harbors such as Sandusky, Cleveland, Fairport, and Ashtabula on the southern shore of Lake Erie. Scores of antiquarian sources from these lake ports provide evidence. Cleveland witnessed its first court case involving runaway slaves in May after the citizens of Hudson forcibly freed two Virginia slaves who had nearly reached the lake and were being returned to bondage. Local people later assisted the runaways in gaining passage to Upper Canada (contemporary Ontario). Trailblazing Underground Railroad historian Wilbur Siebert scoured through local records and memories from these lake ports and found that “runaway slaves were arriving at Painesville in 1820 and embarking from Fairport” and “pioneer settlers of Ashtabula and Ashtabula Harbor were promoting the escape of slaves to Canada by 1820.” Attorney Rush Sloane, who aided many in reaching freedom, noted that “the first runaway slave known as such at Sandusky was there in the fall of the year 1820.” The Kentucky fugitive crossed Ohio on foot, with his master in hot pursuit. Unable to locate his bondsman in Sandusky, the master boarded the steamboat Walk-in-the Water bound for Detroit. Capt. P. Shepard then secretly sailed the slave in another vessel to Fort Malden and liberty on the Canadian side. Ohio’s Lake Erie ports soon [End Page 7] joined the Detroit River and Niagara River frontiers as major crossing points for freedom seekers going to Canada.1 A number of factors made this pioneering exodus possible. Among these, two deserve mention here. First, the advent of steamboats on the lake, beginning with the launch of the Walk-in-the-Water in 1818, made passenger travel between Ohio lake ports and Detroit, Erie, and Black Rock, New York, relatively routine. By the 1820s, sympathetic steamboat captains and crews were helping runaway slaves across Lake Erie. After reaching either Detroit or Black Rock (now part of Buffalo), fugitives crossed easily into Upper Canada. Second, slaves in the Ohio River valley were increasingly aware that they could find freedom in Canada. The 1793 Antislavery Act in Upper Canada placed the province on the road to emancipation. After the War of 1812, veterans returning to their homes in western Virginia and Kentucky brought news about the land of freedom to the north. This circulated quickly through slave communities in the Upper South. John P. Parker, an Underground Railroad worker in Ripley, claimed that “after the War of 1812 every slave knew the north star led to freedom and Canada.” Abolitionist politician Henry Wilson observed that “many of the slaves, catching at these vague items of information, made them the basis of plans of escape …, in entire ignorance of the distance and dangers of the way.” This generalized awareness of Canadian freedom assumed more concrete form after 1819, when John Beverly Robinson, Upper Canada’s attorney general, made it clear to American officials that colonial authorities in the province would oppose any efforts to extradite runaway slaves. “Whatever may have been the condition of the Negroes in the [United States],” he announced, “here they are free—For the enjoyment of all civil rights … and among them the right to personal freedom.” The volume of runaway slaves headed toward Canada expanded exponentially in 1820.2 [End Page 8] Among the first runaway slaves to make the Lake Erie crossing in 1820 were George and Edy Duncan, the property of Samuel Sprigg, common-wealth attorney for western Virginia and a prominent resident of Wheeling. Only seventeen and fourteen years of age, respectively, at the time of their flight, this obscure slave couple displayed the curious mixture of naïveté, courage, and desire that is found most often in the young. Absconding separately from bondage, and reuniting near the end of their journey, they fled Wheeling, crossed the Ohio River, moved through a series of Quaker settlements in east-central Ohio, then two Yankee farmsteads in the Western Reserve, ultimately crossing Lake Erie from Fairport. Most of what can be known about George and Edy’s journey to...

Determinants of plasma homocysteine in coal miners.

Several studies suggest that coal miners are under risk of severe health problems such as cardiovascular, pulmonary, neurological, renal, hematological and musculoskeletal disorders. However, there are limited data on biochemical changes in underground workers. In our study we aimed to evaluate the association between serum homocysteine (Hcy), vitamin B12, cystatin C and folate levels in the blood of underground coal miners. Eighty one coal miners who work as underground or surface workers were recruited into our study. The study population was divided into two groups: the surface worker group (control group, n=33) and the underground worker group (n=48). The folate, vitamin B12, Hcy, cystatin C levels and body mass indexes (BMI) of both groups were measured and compared. Serum folate, Hcy and vitamin B12 levels were measured with a competitive chemiluminescence immunassay. Serum levels of cystatin C were determined by the latex particle-enhanced turbidimetric method using a cystatin C kit. Urea values were measured with a kinetic method on an automated analyzer. There were no statistically significant differences between the underground workers and surface workers in the urea, cystatin C and vitamin B12 levels. High serum Hcy levels and low folate levels were found in underground workers compared with those in surface workers. The correlation between Hcy and folate levels was also statistically significant. Similarly, there was also a significant correlation between Hcy and vitamin B12, and between Hcy and cystatin C levels. Elevated Hcy levels may be associated with underground working but further research is necessary to understand the relation between elevated Hcy and increased prevalence of health problems in coal miners.

Research and Realization for the System of Coal Mine Ventilation System

Coal mining is an integrated trade which involves the geology, well ventilated, transportation, electricity and environmental protection and so on. The mining industry has labor intensity, bad work condition, many harm factors. Each kind of virulent noxious gas, coal dust, fire, electromechanical device are all immediate danger to operate personnel's safety and healthy. Well-balanced and suitable ventilation is the postulate to keep the health of underground worker and the safety of the production. We take air quantity of laneway as the research emphasis, considering the release of state regulations on coal min. We figure out the optimum area of air quantity via building the optimization programming model, and realize an actual case study to interpret the process of the probabilistic risk analysis (PRA) with statistic theory. We take the theory to the actual production. We establish a MIS base on the theory. In the process of establishing the system, we use the object-oriented analysis method and the B/S structure, take JAVA as the development kit, and realize the risk analysis system. Then the risk manager can take the corresponding monitoring measure.

Mortality of a cohort of tin miners 1941-86.

The mortality patterns of United Kingdom tin miners were examined in relation to calendar period and duration of underground work with particular attention to lung cancer and exposure to radon. Subjects were all men who had worked for at least one year between 1941 and 1984 at one of two United Kingdom tin mines and for whom a complete work history could be constructed from mine records. Standardised mortality ratios (SMRs) were calculated using national (England and Wales) rates. The pattern of SMRs in relation to potential explanatory variables was analysed using Poisson regression methods. Mortalities from lung cancer and silicosis (including silicotuberculosis) were significantly raised and showed a significant relation with duration of underground work (mortality from stomach cancer was raised in both underground and surface workers, but not significantly). Excess mortality from silica related disease declined steeply from 35% among workers first exposed before 1920 to 1% among those first exposed after 1950. Thirteen surface workers with known exposure to arsenic had high rates of lung and stomach cancer. The SMR for lung cancer showed a consistent pattern in relation to duration of underground exposure, rising from 83 (observed/expected = 8/9.6) for surface workers (without exposure to arsenic) to 447 (15/3.4) for workers with more than 30 years underground exposure. Examination of the SMR for lung cancer by total underground exposure, age, and time since last exposure gave rise to a model for the expression of risk which depends only on total exposure and time since exposure. The fitted model implies that the effect of exposure to radon in a given year has no effect on risk for 10 years, then rapidly rises to a maximum from which the excess risk then declines, halving every 4.3 years. There were no direct measurements of historic radon levels. A conservative estimate based on measurements taken since 1969 by the National Radiological Protection Board and the Mines and Quarries Inspectorate is that the annual dose to an underground worker was about 10 working level months (WLM). Given this assumption, the risk/exposure slope implied by the present data, and the model fitted to it, was somewhat lower than that given in the fourth Committee on the Biological Effects of Ionisation Radiation (BEIR IV) report (about 40% lower for lifetime exposures). The present data also imply different risks depending on the age at exposure, with relatively higher lifetime risks for exposure at older ages, and relatively lower risks for exposures at younger ages. In conclusion, there was a clear relation between exposure to radon and death from lung cancer. The relative risk of lung cancer due to exposure to radon was not constant in cessation of exposure. The lifetime excess risk of lung cancer implied by these data for 40 years exposure at the current statutory limit of four WLM a year starting at age 20, was about 8% (79 excess deaths per 1000 exposed), assuming average smoking habits among the exposed workers. Control of dust concentrations in the mines has substantially reduced--and may have eliminated--direct mortality from silica related disease.

Salto de Miranda. Trabajos de excavación de la galería

The first article of this series was published in issue N.° 162 of «Informes de la Construccion», under the title «Salto de Miranda». The present article deals with the work of excavating the gallery. Modern practice requires that to do this type of work successfully the auxiliary material should be most carefully studied beforehand. N.° 164 of the this magazine has included a paper entitled «Recent progress in the auxiliary material for underground gallery excavation», summarising the most recent type of machinery now available in the market. Since the Grand Coulee Dam was built by the Bureau of Reclamation, where essentially new techniques were introduced, including minimum times for maximum progress, these new procedures and equipment have been generally adopted throughout the world. To this must be added the urgent and increasing demands for electric power, and the vast amounts of money involved in these hydroelectric projects, which explain the rapid adoption of automatic procedures in this kind of work. In this paper the author explains how, using the means available to him, he sought to coordinate the various constructional tasks, to get as near as possible to the most economic working cycle. Underground ventilation is an acute problem, and involves the safety of those working inside the tunnel. The author explains, in simple terms, how the theory of fluids and air circulation can affect the rational and practical solution of providing adequate air supply for the health and comfort of the underground worker. To attain this end, however, a considerable mechanical and economic investment is necessary.

A review of 102 cases of beat conditions of the knee.

In mining, as in other occupations, entry into the groups qualifying for the higher wage rates is determined by qualification as a skilled man. For the underground worker this means production at, or close to, the coal face, and in coalfields in which the seams are comparatively thin, much of the miner's working time is spent in the performance of hard work while kneeling. With seams about 3 ft. in thickness, anything from 25% to 100% of the working shift of seven hours or so may be spent on the knees. The common disorders of the knee which occur in men working in thin seams of coal are very well known to miners under the collective term of beat knee . Beat knee is a prescribed disease under the National Insurance (Industrial Injuries) Act 1946, and is defined officially as subcutaneous cellulitis or acute bursitis arising at or about the knee . Although the definition excludes synovial effusions into the knee joint, internal derangements of the joint, osteo-arthritis, and other morbid con ditions well represented in miners, the incidence of beat knee is high. The number of cases receiving injury benefit for this condition averaged 10,305 per annum in Great Britain for the three years 1952-54. The present paper is based on 102 cases of beat knee seen consecutively in a period of two and a half years in one area of the North Eastern (York

The Health of the underground Worker

The Health of the underground Worker

Safeguarding the use of electricity in mines

The sources of danger attending the use of electricity in mines are shocks, fires and explosions. Shocks are the electrical accidents that happen most frequently underground, the conditions there being especially favorable to the occurrence of such mishaps. Fires may be caused by leaks to ground, short circuits and blowing fuses. Injuries to electrical equipment, due to falls of roof often add to the fire hazard. Explosions may be result of the ignition of explosives, mine gas or coal dust. The paper discusses the underground conditions that are unfavorable to the proper installation and maintenance of electrical equipment and suggests, in general terms, some methods of making safer the use of electrical equipment in mines. These suggesions are finally summarized briefly under five heads. The closing paragraphs of the paper discuss electrical equipment as a means of promoting safety and mentions the telephone, the portable electric lamp, electric shot firing devices and storage battery locomotives as equipment that may be regarded as lessening the risks surrounding the underground worker.

Safeguarding the Use of Electricity in Mines

The sources of danger attending the use of electricity in mines are shocks, fires and explosions. Shocks are the electrical accidents that happen most frequently underground, the conditions there being especially favorable to the occurrence of such mishaps. Fires may be caused by leaks to ground, short circuits and blowing fuses. Injuries to electrical equipment, due to falls of roof often add to the fire hazard. Explosions may be result of the ignition of explosives, mine gas or coal dust. The paper discusses the underground conditions that are unfavorable to the proper installation and maintenance of electrical equipment and suggests, in general terms, some methods of making safer the use of electrical equipment in mines. These suggesions are finally summarized briefly under five heads. The closing paragraphs of the paper discuss electrical equipment as a means of promoting safety and mentions the telephone, the portable electric lamp, electric shot firing devices and storage battery locomotives as equipment that may be regarded as lessening the risks surrounding the underground worker.

The Slate Mines of Merionethshire1

AN official Blue Book drawn up by a Departmental Committee appointed by Mr. Asquith, and referring to the dangers of slate quarrying in Merionethshire, has recently appeared. After a brief account of the mode of occurrence, the method of getting the slate by true mining operations is described, and the principal causes of accidents are enumerated and explained. Judging by the statistics of the last nineteen years, the underground worker in Merionethshire is exposed to greater risks than the average collier; some 40 per cent, of the deaths are caused by falls of rock, a fact which causes no surprise when one considers the conditions under which the slate-getters carry on their daily work in huge chambers, the roofs and sides of which cannot be examined without rigging up lofty ladders.