Interior Thermal Environment of a 6-Person Metal-Type Refuge Alternative (RA)

Author(s):  
Lincan Yan ◽  
David Yantek ◽  
Mark Klein ◽  
Peter Bissert

In 2008, the Mine Safety and Health Administration (MSHA) published a final rule on Refuge Alternatives (RAs) for Underground Coal Mines [1]. The rule states that RAs should be “capable of sustaining trapped miners for 96 hours” and that RAs “can also be used to facilitate escape by sustaining trapped miners until they receive communications regarding escape options.” One of the main concerns with the use of RAs is heat and humidity buildup inside of them. The accumulation of heat and humidity could result in miners suffering heat stress or even death. MSHA regulations require that the apparent temperature in an occupied RA must not exceed 95°F. To investigate the thermal issues for occupied RAs, the National Institute for Occupational Safety and Health (NIOSH) conducted several tests on mobile RAs. In this paper, the test setup on a 6-person metal-type RA is described and the test results are presented. The test results show that the average measured air temperature within the RA increased by 9.0°C (16°F) and the relative humidity (RH) approached 91 %RH at the end of the 96-hour test. The test results were also compared to predictions from a thermal simulation model of the tested RA. The model predicted the average air temperature inside the RA at the end of 96 hours to within 0.4°C (0.8°F) of the average measured air temperature. Furthermore, two sets of test data with different heat inputs were used to cross-check the model validity.

Author(s):  
Lincan Yan ◽  
David Yantek ◽  
Pete Bissert ◽  
Mark Klein

Mine Safety and Health Administration (MSHA) regulations require underground coal mines to use refuge alternatives (RAs) to provide a breathable air environment for 96 hrs. One of the main concerns with the use of mobile RAs is the heat and humidity buildup inside the RA. The accumulation of heat and humidity can result in miners suffering heat stress or even death. To investigate this issue, the National Institute for Occupational Safety and Health (NIOSH) conducted testing on a training ten-person, tent-type, RA in its Safety Research Coal Mine (SRCM) in a test area that was isolated from the mine ventilation system. The test results using sensible and latent heat showed that the average measured air temperature within the RA increased by 20.6°F (11.4°C) and the relative humidity approached 90 %RH. The test results were used to benchmark a thermal simulation model of the tested RA. The validated thermal simulation model predicted the average air temperature inside the RA, at the end of 96 hours, to within 1°F (0.6°C) of the measured average air temperature.


Author(s):  
Lincan Yan ◽  
David Yantek ◽  
Timothy Lutz ◽  
Jeffrey Yonkey ◽  
Justin Srednicki

Abstract In case of an emergency in an underground coal mine, miners who fail to escape from the mine can enter a refuge alternative (RA) for protection from adverse conditions, such as high carbon monoxide levels. One of the main concerns with the use of both portable and built-in-place (BIP) RAs, especially for hot or deep mines, is the interior temperature rise due to the occupants' metabolic heat and the heat released by devices such as the carbon dioxide (CO2) scrubbing system. The humidity within the RA will also increase through occupants' respiration and perspiration and from the chemical reaction within the CO2 scrubbing system. Heat and humidity buildup can subject the occupants to hazardous thermal conditions. To protect RA occupants, Mine Safety and Health Administration regulations mandate a maximum apparent temperature of 95 °F within an occupied RA. The National Institute for Occupational Safety and Health (NIOSH) tested both an air-conditioned borehole air supply (BAS) and a cryogenic air supply for RAs in the NIOSH Experimental Mine in Bruceton, PA. The BAS was tested on a 60-person BIP RA, while the cryogenic air supply was tested on a 30-person BIP RA and a portable 23-person tent-type RA. Multiple tests were conducted with both air supplies to assess their ability to cool RAs. The test results show that the BAS and the cryogenic air supply were able to maintain the apparent temperature within the tested RAs under the 95 °F limit. The BAS and the cryogenic air supply are potential RA heat mitigation strategies that mines could use to prevent heat/humidity buildup within RAs.


Author(s):  
Nicholas W. Damiano ◽  
Chenming Zhou ◽  
Bruce Whisner

In 2008, the Mine Safety and Health Administration (MSHA) published a final rule on Refuge Alternatives (RAs) for Underground Coal Mines. The rule states that RAs shall be capable of sustaining trapped miners for 96 hours and that RAs can also be used to facilitate escape by sustaining trapped miners until they receive communications regarding escape options. As of 2014, there were three types of coal mine RAs manufactured by 10 different companies and at least 13 different communications systems approved for use underground. However, there is no specific guidance on how to determine if such a wide variety of systems will facilitate successful communication in an emergency. Examples in this study detail one representative example of each of the three types of RAs. Each example RA was tested underground in an experimental coal mine by researchers from the National Institute for Occupational Safety and Health (NIOSH). The purpose of the testing was to determine a representative signal attenuation caused by a specific RA’s wall material and entrance door. For each RA type, the signal loss was investigated using comparative measurements. Test results showed an average difference of 3 decibel milliwatts (dBm) for a tent type RA, 15 dBm for a metal RA and 14 dBm for a Built-in-Place RA for a frequency range of 150 to 3000 MHz. These results can be used in calculating the available link budget for a communication system to determine if a signal will reach the inside of the RA.


Author(s):  
Lincan Yan ◽  
David Yantek ◽  
Timothy Lutz ◽  
Jeffrey Yonkey ◽  
Justin Srednicki

In case of an emergency in an underground coal mine, miners who fail to escape from the mine can enter a refuge alternative (RA) for protection from adverse conditions, such as high carbon monoxide levels. One of the main concerns with the use of both portable and built-in-place (BIP) RAs, especially for hot or deep mines, is the interior temperature rise due to the occupants’ metabolic heat and the heat released by devices such as the carbon dioxide (CO2) scrubbing system. The humidity within the RA will also increase through occupants’ respiration and perspiration, and from the chemical reaction within the CO2 scrubbing system. Heat and humidity buildup can subject the occupants to hazardous thermal conditions. To protect RA occupants, Mine Safety and Health Administration regulations mandate a maximum apparent temperature of 95°F within an occupied RA. The National Institute for Occupational Safety and Health (NIOSH) tested both an air conditioned borehole air supply (BAS) and a cryogenic air supply for RAs in the NIOSH Experimental Mine in Bruceton, PA. The BAS was tested on a 60-person BIP RA, while the cryogenic air supply was tested on a 30-person BIP RA and a portable 23-person tent-type RA. Multiple tests were conducted with both air supplies to assess their ability to cool RAs. The test results show that the BAS and the cryogenic air supply were able to maintain the apparent temperature within the tested RAs under the 95°F limit. The BAS and the cryogenic air supply are potential RA heat mitigation strategies that mines could use to prevent heat/humidity buildup within RAs.


Author(s):  
Lincan Yan ◽  
David Yantek ◽  
Mark Klein ◽  
Peter Bissert ◽  
Rudy Matetic

Mine Safety and Health Administration (MSHA) regulations require underground coal mines to install refuge alternatives (RAs). In the event of a disaster, RAs must be able to provide a breathable air environment for 96 h. The interior environment of an occupied RA, however, may become hot and humid during the 96 h due to miners' metabolic heat and carbon dioxide scrubbing system heat. The internal heat and humidity may result in miners suffering heat stress or even death. To investigate heat and humidity buildup with an occupied RA, the National Institute for Occupational Safety and Health (NIOSH) conducted testing on a training ten-person, tent-type RA in its Safety Research Coal Mine (SRCM) in a test area that was isolated from the mine ventilation system. The test results showed that the average measured air temperature within the RA increased by 11.4 °C (20.5 °F) and the relative humidity approached 90% RH. The test results were used to benchmark a thermal simulation model of the tested RA. The validated thermal simulation model predicted the average air temperature inside the RA at the end of 96 h to within 0.6 °C (1.1 °F) of the measured average air temperature.


Author(s):  
Gregory R. Wagner ◽  
Emily A. Spieler

This chapter discusses the roles of government in promoting occupational and environmental health, with a focus on the U.S. federal government. Governmental interventions, as described here, can range from non-regulatory interventions, such as dissemination of information or generation and communication of information, to establishing regulatory requirements through the promulgation and enforcement of standards and regulations. The chapter describes the U.S. laws and roles of the administrative agencies responsible for occupational and environmental health, including the Occupational Safety and Health Administration, the Mine Safety and Health Administration, and the Environmental Protection Agency. Noting the budgetary and political constraints on these federal agencies, the chapter goes on to discuss briefly the role of the public and the states. The government also plays a role when preventive efforts fail, and the chapter provides a brief summary of programs designed to provide compensation to injured workers.


2021 ◽  
Vol 13 (13) ◽  
pp. 7047
Author(s):  
Nu Yu ◽  
Yao Zhang ◽  
Mengya Zhang ◽  
Haifeng Li

Cabin air quality and thermal conditions have a direct impact on passenger and flight crew’s health and comfort. In this study, in-cabin thermal environment and particulate matter (PM) exposures were investigated in four China domestic flights. The mean and standard deviation of the in-cabin carbon dioxide (CO2) concentrations in two tested flights are 1440 ± 111 ppm. The measured maximum in-cabin carbon monoxide (CO) concentration is 1.2 ppm, which is under the US Occupational Safety and Health Administration (OSHA) permissible exposure limit of 10 ppm. The tested relative humidity ranges from 13.8% to 67.0% with an average of 31.7%. The cabin pressure change rates at the end of the climbing stages and the beginning of the descending stages are close to 10 hPa·min−1, which might induce the uncomfortable feeling of passengers and crew members. PM mass concentrations were measured on four flights. The results show that PM concentrations decreased after the aircraft cabin door closed and were affected by severe turbulences. The highest in-cabin PM concentrations were observed in the oldest aircraft with an age of 13.2 years, and the waiting phase in this aircraft generated the highest exposures.


2017 ◽  
Vol 9 (2) ◽  
pp. 81-82
Author(s):  
George R. Cook

Occupational audiologists have a crisis in their profession and need advocates. These audiologists are primarily responsible for industrial hearing conservation programs and their compliance with multiple regulations, such as Occupational Safety and Health Administration (OSHA), Mine Safety and Health Administration (MSHA) and the Federal Railroad Administration.  Occupational hearing programs, for the most part, are multi-state programs as companies and corporations are national organizations. Also, companies may contract services across state lines as local services may not be desired or available. Individual state telepractice regulations require audiologists who are professionally supervising these programs via the internet and phone, to secure licensure in each state. For this licensure redundancy, the cost in time and tracking are enormous.  It is imperative that the American Speech-Language-Hearing Association (ASHA), secure multistate licensure for speech-language pathologists and audiologists. For the profession of occupational audiology, it is essential.Keywords: Licensure, Occupational audiologists, Telehealth, Telepractice


2020 ◽  
Vol 110 (5) ◽  
pp. 622-628
Author(s):  
David Rosner ◽  
Gerald Markowitz

As this short history of occupational safety and health before and after establishment of the Occupational Safety and Health Administration (OSHA) clearly demonstrates, labor has always recognized perils in the workplace, and as a result, workers’ safety and health have played an essential part of the battles for shorter hours, higher wages, and better working conditions. OSHA’s history is an intimate part of a long struggle over the rights of working people to a safe and healthy workplace. In the early decades, strikes over working conditions multiplied. The New Deal profoundly increased the role of the federal government in the field of occupational safety and health. In the 1960s, unions helped mobilize hundreds of thousands of workers and their unions to push for federal legislation that ultimately resulted in the passage of the Mine Safety and Health Act of 1969 and the Occupational Safety and Health Act of 1970. From the 1970s onward, industry developed a variety of tactics to undercut OSHA. Industry argued over what constituted good science, shifted the debate from health to economic costs, and challenged all statements considered damaging.


2020 ◽  
Vol 77 (6) ◽  
pp. 402-406
Author(s):  
Noemi B Hall ◽  
David J Blackley ◽  
Cara N Halldin ◽  
A Scott Laney

ObjectivesPneumoconiosis prevalence and severity among US coal miners has been increasing for the past 20 years. An examination of the current approaches to primary and secondary prevention efforts is warranted. One method of secondary prevention is the Mine Safety and Health Administration-administered part 90 option programme where US coal miners with radiographic evidence of pneumoconiosis can exercise their right to be placed in a less dusty area of the mine. This study focuses on characterising the progression of disease among US coal miners who participated in the National Institute for Occupational Safety and Health-administered Coal Workers’ Health Surveillance Programme (CWHSP) and exercised their part 90 job transfer option.MethodsChest radiograph classifications of working underground coal miners who exercised their part 90 job transfer option during 1 January 1986 to 21 November 2016 and participated in the CWHSP during 1 January 1981 to 19 March 2019 were analysed.Results513 miners exercised their part 90 option and participated in the CWHSP at least once during this time period. Of the 149 miners with ≥2 radiographs available, 48 (32%) showed progression after exercising part 90 and had more severe disease prior to exercising, compared with miners who did not progress (severity score of 2.8 vs 1.7, p=0.0002).ConclusionThe part 90 job transfer option programme is not routinely used as intended to prevent progression of pneumoconiosis among US coal miners. The one-third of miners who participated in part 90 and continued to progress, exercised their part 90 option at a later stage of disease compared with non-progressors.


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