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Principles Of Mine RescueThe information presented on this page was taken from the Bureau of Mines Instruction Guide 16, "Principles of Mine Rescue" by the Division of Education and Training Services, U.S. Department of the Interior, Bureau of Mines, Health and Safety Activity, Office of Education and Training, November, 1972.
Plan of Surface Organization and Procedure In Case of a Mine Fire or ExplosionPrearranged Plan of Surface OrganizationEvery mine should perfect a firefighting and rescue organization. Practice drills should be held at least twice a year. All underground mining personnel should be familiar with their duties in the case of disaster. Underground officials should plan in advance the detailed course of action in the event that they and their men are trapped following a fire or other disaster. In addition, workers should be instructed in the use and construction of barricades. They should be familiar with the course of the ventilation of the mine section where they work. Thus, rescue equipment, accessories, and trained personnel should be maintained and available for emergency use. Paragraph (a) of 30 CFR Section 75.1101-23 provides that the operator shall adopt a program for the instruction of miners in the location and use of fire fighting equipment; the location of escapeways, exits, and routes of travel to the surface; and the proper evacuation procedures to be followed in the event of an emergency. Such program shall be submitted for approval to the District Manager of the Coal Mine Health and Safety District in which the mine is located. 30 CFR Section 57.4-30, concerning underground metal and nonmetallic mines, states "employees should be trained in the use of firefighting equipment." 30 CFR Section 57.4-31 states "a firefighting organization should be established, equipped, and trained in firefighting and that drills should be held at least twice a year." Procedure in Case of Coal Mine Fire or ExplosionEvacuate underground workers immediately. Notify at once and in the order given the following supervisory, administrative, and governmental authorities:
Changes in the order of notification may be made when necessary, depending upon up-to-date regulations governing the mine. As soon as they are notified, company officials should contact other officials who are responsible to them and should carry out a firefighting and rescue operation according to the prearranged plan. All personnel assigned to the rescue organization should practice their respective duties by frequent drills and should be capable of performing them efficiently in an emergency.
The Superintendent or other official in charge should-
Guards should-
The Outside Foreman should-
The Mine Clerk should-
The Supply Clerk should-
The Electrician should-
The Mechanical Foreman should-
The Lamp Man should-
The Mine Foreman should-
The Checkman should-
The Chief Engineer should-
Other Superintendents and Foremen should-
The Director of Safety and Inspection should- An information center should be established to issue information to friends and relatives of the trapped men and to the press and public.
NOTE - It is suggested that someone be placed in charge of friends, relatives, and the press to keep them in a safe location away from the rescue operations and to prevent their receiving information based on speculation that could result in unnecessary grief and erroneous information being released. Procedure Following Mine FiresMethods of Controlling and Extinguishing Mine FiresFighting Mine Fires by Direct Attack1. Water may be applied by hoses in large streams or fine spray.
2. Chemicals in approved-type extinguishers may be used to control fires.
3. Fine limestone or shale dust for rock-dusting bituminous coal mines can be used successfully in fighting fires in the early stages and also for larger fires under some conditions. Rock dust serves to exclude oxygen from the heated area and may also serve to reduce the heat of the burning material. Covering burning material with rock dust does not produce fumes as does the use of chemicals, nor does it produce steam and hydrogen as does the use of water.
4. Fine sand can be used in making a direct attack in essentially the same manner as rock dust. However, sand is heavier than dust and, therefore, more difficult to handle. Because of its use in mine safety operation, rock dust is usually available in sacks of a convenient size for handling, whereas sand would have to be hauled in especially for firefighting. 5. The foam generator is effective in fighting stubborn localized fires that are not accessible to direct attack. Several models of foam generators are available. They are ideal because they can be driven down the entries to mine fires which are otherwise inaccessible.
Sealing Mine FiresTemporary Stoppings or SealsTemporary stoppings or seals generally are constructed of a wooden frame and brattice cloth or canvas because they can be erected quickly and can be made fairly tight. Wood stoppings are not tight unless plastered, which takes considerable time. Temporary stoppings should be set an adequate distance inby the opening. This sealing will allow enough room to erect permanent stoppings outby the temporary stoppings, if feasible. Construction of a temporary stopping should provide sufficient strength and a tight seal. 1. Brattice cloth.
2. If brattice cloth is not available, wood may be used.
Permanent Stoppings or Seals1. Stoppings or seals constructed of brick usually are satisfactory inasmuch as brick withstands crushing about as well as most material. The size of a brick is well adapted to constructing a wall conforming to the shape of an opening. It should be well hitched in the floor, ribs, and roof.
2. Cement blocks laid with strong cement mortar may be used to erect permanent seals or stoppings .
3. Concrete stoppings are durable, unaffected by water, have a high bearing strength, and assist in supporting the roof.
4. A stopping or seal can be constructed more quickly of tile than of smaller brick.
5. Wood and plaster stoppings have been used successfully.
6. Several types of pack-wall stoppings have been used successfully.
7. Water may be flooded into mines to stop fires.
8. A combination of dust and water control is sometimes used to flush mine fires.
9. Incombustible barriers have been used successfully in several abandoned coal mines to prevent the spread of fire.
10. Inert gas such as carbon dioxide occasionally may be used to advantage in cooling or extinguishing a mine fire, although the process is expensive.
Unsealing Mine FiresExperience and scientific study have shown that no attempts should be made to unseal a mine fire (1) until the oxygen content of the sealed atmosphere is low enough to make explosions impossible, and (2) until the carbon monoxide, the indicator of combustion, has disappeared or nearly so. These conditions are difficult to achieve in many cases. 1. The extent and intensity of the fire at the time of sealing will have a decided bearing upon the reduction of oxygen in the area. 2. The characteristics of burning material and the overlying and underlying strata are factors to be considered.
3. Tight seals are essential for control of oxygen. Barometric pressure affects sealed areas. 1. Excess outside pressure causes air to enter. 2. Lower pressure outside assists in the escape of the sealed atmosphere (CH4, CO, Cot, etc.). 3. It may be of considerable importance to know the barometric pressure of the sealed area at the time of sealing. If the temperature outside of the mine is considerably lower than the mine temperature, inward pressure on the fire seals is likely to occur; if higher, outward pressure will occur. 1. As the fire cools, inward pressure results. 2. If the stoppings are hot or warm, the temperature within the sealed region is high. In a sealed area where the air current passes on two sides, namely the intake and return, a difference in pressure exists that may induce leakage through the stoppings and strata. These leakages could prolong extinguishment of the fire. When the pressure is outward only, samples of the atmosphere behind stoppings should be taken at least once every 24 hours for the first few days of the fire. 1. Using an aspirator bulb or pump, samples may be collected by vacuum tube, water displacement, and air displacement. 2. After the samples are collected, they must be kept pure and analyzed accurately. The gases usually found in sealed regions mainly contain methane, hydrogen, carbon monoxide, carbon dioxide, nitrogen, and oxygen. 1. The extent to which oxygen should be reduced under sealed conditions depends upon the relative quantities of combustible gases present. 2. It is desirable that the amount of oxygen be reduced to at least 3 percent and preferably below 1 percent before an attempt is made to unseal. In addition, the time for unsealing may be determined by local factors such as the proximity of gas wells, the position of boreholes, the extent of the region under seal, and the temperature within the sealed area. The successful opening of a fire area necessitates certain preparations. 1. Adjustments in ventilation should be made to direct fire gases from the sealed region into the main return. 2. An attendant should be at the mine fan to see that it is correctly operating. If the fan slows down, or other change is noted, the men engaged in the unsealing work must be warned immediately. 3. Electrical power must be cut off from the section of a coal mine in which a fire is sealed before the work of unsealing is undertaken. 4. In bituminous coal mines, all entries and crosscuts leading to and from the fire region should be coated heavily with rock dust for a considerable distance outby the seals that are to be opened. Methods of Unsealing Mine FiresWhen the sealed area is large, the fire extensive, or bodies must be removed, the region is recovered in sections by using air locks and advancing to a point where the bodies can be reached. 1. Air locks consist of two stoppings 10 or 15 feet apart equipped with doors through which crews equipped with oxygen breathing apparatus can enter and take material into the sealed area.
2. Air-locking operations should never be undertaken until the oxygen content of the air in the area behind the seals has been reduced to at least 2 percent. Once a suitable air lock has been erected, proper organization and adequate equipment and materials should have been provided and all other necessary arrangements should have been completed. 3. Recovery teams using oxygen breathing apparatus (one in reserve) should enter the air lock and remove the seal. 4. The first crew should return to the air lock and allow a second crew to inspect the area beyond the seal to select a place for the next air lock. They should return with an atmosphere sample. 5. A crew should then proceed with the construction of a second air lock according to the plan and information provided by the reconnaissance crew. 6. As each crew advances into the area beyond an air lock, designated members should sample the atmosphere for oxygen content, combustible gases, and temperature. When a sealed region is to be recovered by direct ventilation, an air lock should be constructed, preferably near the intake seal. 1. A rescue crew with a communication system and other necessary equipment should break the seal, enter, observe conditions, take temperature readings and air samples, and return to the fresh air base. 2. If inspection of the affected region shows that conditions are favorable, the return seal should be broken by an apparatus crew. 3. The air lock should then be opened to admit air. 4. The area should be ventilated and, if possible, the combustible gases in the main return should be kept below the lowest explosive limit. Recovery Procedure Following a Mine ExplosionExamination of Mine OpeningsBefore exploring is begun, a preliminary examination should be made of all openings and escapeways because men overcome by afterdamp may be found near openings. Tests for methane, carbon monoxide, and smoke can aid in determining the order in which the openings should be explored. Establishing VentilationIf the ventilation fan has not been destroyed or damaged, it should be kept running. Entering Mine and Establishing Fresh Air BaseWhen the necessary organization has been formed, equipment and materials assembled, and ventilation established, exploration of the mine should be started. Continual checking of return air for mine gases and smoke is necessary. Establishing Telephone CommunicationAs recovery work progresses, the telephone system should be extended to stay abreast of rescue efforts. Additional telephones should be installed so that a telephone will always be available to the advance crews. Ordinary telephones should not be installed or left where they are likely to come in contact with explosive gas. In such areas, only permissible telephones should be used. Duties of Rescue and Recovery CrewsRescue crews should consist of men with gas masks or oxygen breathing apparatus trained and equipped to make explorations, to work in irrespirable air, and to rescue mining personnel.
Recovery crews are composed of brattice men, men for handling and transporting material, telephone attendants, timbermen, trackmen, and other related personnel. They should not be permitted to go ahead of fresh air, since they may be overcome, or their efficiency may be reduced, by breathing harmful gases. Explorations Ahead of Fresh AirAfter a fresh air base has been established, exploring should be done ahead of fresh air by rescue crews wearing oxygen breathing apparatus. 1. The crews should look for live men, spot fires, locate bodies, and observe conditions. 2. The length of trips from the fresh air base should be determined by local conditions. 3. When oxygen breathing apparatus crews are working ahead of fresh air, another oxygen breathing apparatus crew, equipped with adequately charged apparatus in good condition,should always be held in reserve at the air base. Before leaving the fresh air base, the exploration crew should be instructed by the man in charge to examine and test the equipment, to go only a certain distance, to examine for specified conditions, to observe specified places, and to return in a specified length of time. During exploration trips ahead of fresh air, rescue crews should follow previous instructions and consider personal safety at all times. 1. After proceeding about 50 to 100 feet into the area away from the fresh air base, the apparatus of each crewman should again be examined by the team captain to assure satisfactory performance and the ability of each member to continue and perform the required mission. 2. Then, carrying a lifeline for giving signals or a batteryless or permissible battery-type portable telephone and wire, they should proceed slowly in single file about 6 feet apart. 3. They should examine the roof and roadway and make a running record of progress on the surfaces of the mine.
Restoring VentilationIf an explosion has affected a large area, many temporary stoppings will be required to restore ventilation. 1. Temporary stoppings should be constructed in the manner described. 2. Near mine openings or other places where they will be subjected to considerable pressure, temporary stoppings should be constructed with two to four plies of brattice cloth or plastic material, depending on the size of the stopping and the distance the air must be carried. 3. Temporary stoppings should be set at least 4 to 6 feet inby crosscuts or other openings to leave space for later construction of stronger and tighter stoppings. 4. As soon as possible, semipermanent stoppings of boards or stronger material, or permanent stoppings of brick, cement blocks, tile, or concrete should be erected to replace temporary stoppings. 5. A man should be assigned on each shift to patrol all temporary stoppings and to keep them as airtight as possible. In ventilating any portion of a mine after an explosion, the afterdamp should be conducted to the outside by the most direct route. 1. For maximum safety currents of air are conducted so that ventilation will always be under the control of the man in charge of the shift and the path the air is traveling will always be definitely known. 2. If possible, all sections, entries, rooms, and other open accessible workings should be cleared of afterdamp as work advances. 3. Line brattice will be required for ventilating faces of entries and rooms or to split the air current in entries when it is necessary.
Dealing With Fires Encountered During ExplorationIf fires are found while rescue crews are exploring ahead of fresh air, they should be extinguished with water, rock dust, or fire extinguishers before the fresh air advances to the fire. If a fire is of such proportions that it cannot be extinguished, it should be sealed promptly and effectively. If smoke and an explosive mixture of gas are encountered and the location of the fire in unknown, it may be advisable to seal the region containing the fire, or the entire mine. In some situations it will be necessary to use air locks to work around the sealed areas in order to continue recovery operations. The individual circumstances will determine the action to be taken. Rescue and Removal of Live MenSometimes live men are found in the open passageways inby the fresh air lock. 1. Usually they are suffering from poisonous or asphyxiating gases, burns, or injuries. 2. Men found to be affected or overcome in an atmosphere containing afterdamp should have oxygen breathing apparatus placed on them and should be carried to fresh air as soon as possible. As soon as possible after live men are brought to safe air, they should be given additional oxygen to breathe. 1. The oxygen should be administered for at least 30 minutes to remove carbon monoxide from the blood. 2. If rescued men are breathing slowly, or not at all, but show signs of life, artificial respiration should be administered in conjunction with the oxygen. Occasionally, live men are found behind barricades erected to protect themselves from afterdamp. 1. If fresh air can be advanced to the barricades within a short time, this should be done before the barricade is opened. 2. If fresh air cannot be conducted to the barricade in a reasonbly short time, air not able to sustain life should be excluded from the barricade. This can be accomplished by erecting a tight canvas stopping with a small opening covered with canvas a short distance (about 10 to 15 feet) outby the barricade to allow sufficient room to set a stretcher lengthwise between the stopping and the barricade. 3. After the stopping has been erected, an opening large enough to admit an open stretcher should be made in the barricade and covered immediately with canvas. After arrangements have been made to exclude the contaminated air from the area in which the men are located, the live men should be rescued. 1. If men found behind a barricade can walk, they should be provided with the necessary apparatus and assisted to fresh air. 2. If they are unable to walk, they should be carried out on a stretcher.
Handling BodiesAll bodies found in the mine should be wrapped in brattice cloth or canvas by the recovery crews and transported to the morgue. The company should have provisions for such needs. 1. When the bodies are not recovered for several days, they should be sprayed well with a disinfectant, such as Creolin or Lysol, before being touched, handled, or wrapped. It is suggested that rubber gloves be used. 2. A tag bearing an identifying number and the location where the body was found should be attached to each body. 3. If the location has not been marked previously on the roof or rib, this should be done by the recovery crew. 4. The location, position of the body, and check number or name also should be marked on the mine map. 5. Nothing should be removed from the body while it is in the mine, except in the presence of witnesses when a written record is made of the material removed. 6. Items removed from a body should be given to a designated person to be turned over to the morgue official or relatives of the victim. The official in charge of the morgue should assign a morgue number to each body received at the morgue. 1. If possible, body identification should be made with the primary source related to the mine check-in and check-out system required by law (75.1715). 2. A record should be made of tags attached to the recovery crew, the check number, clothing, shoes or boots, money, watch or other jewelry found on the body. 3. A description should be recorded including features, color of hair and eyes, height, weight, teeth, old scars or fractures, and probable age of the victim. 4. All articles removed from a victim should be properly wrapped, tagged, and delivered to the coroner or the victim's relatives. Setting TimbersTimber crews should remove dangerous roof and set necessary timbers as soon as possible, as protection for rescue and recovery crews and others who are required to travel roadways, manways, and entries. Clearing RoadwaysRoadways should be cleared of falls and debris. Necessary repairs should be made to the haulage tracks as soon as possible after an explosion. However, if tests indicate explosive gas accumulations, trolley-pole or cable-reel locomotives may not be used because of the hazards of igniting explosive gases. Battery-powered transportation equipment should be used. Preparation for Resuming OperationsAfter the inspectors and mine officials have completed their investigations, crews should make any repairs necessary to prepare the mine for safe operation. When all the necessary repairs and changes have been made, the State and Federal mine inspectors will inspect the mine--in order to terminate or modify orders that have, of necessity, been issued--before regular work is resumed.
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