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Analyses of air samples given in table 1 show that ventilation was inadequate in the 4 west section as the air contained less than 20 percent oxygen and more than 0.5 percent carbon dioxide.
*1. The fan should be installed on the surface in a fireproof housing and be offset at least 25 feet from the nearest side of the mine opening.
2. Ample pressure relief or explosion doors should be provided.
*3. The quantity of air reaching the last open crosscut in any pair of working. entries should be at least 6,000 cubic feet a minute.
*4. Entry stoppings should be constructed of incombustible material.
*5. Main doors should be erected in pairs to form air locks; they should not be provided with latches.
*6. A split ventilation system utilizing air crossings should be used instead of doors for conducting ventilation in all main passageways.
*7. Intervals between crosscuts should not exceed 60 feet.
*9. Places should not be worked on an air current that has passed through abandoned workings that are not or cannot be regularly inspected.
*10. Haulage and hoisting openings and main and intermediate haulageways should be on intake air. It is recognized, particularly in view of war conditions, that changes in ventilation to comply with this standard are of such magnitude that it would be impracticable to carry them out at present. However, such changes should be made as soon as feasible.
*11. All entries, rooms, or sections that cannot be well ventilated and inspected, or are not used for coursing the air or transportation, should be sealed by strong fireproof stoppings.
12. Mine examiners should not use locomotives for transportation when making inspections.
*13. Air in which men are required to work or travel should contain at least 20 percent oxygen and not more than 0.5 percent carbon dioxide.
MINE DUSTS AND ROCK DUSTING Accumulations of coal dust were noted along haulage roads and in rooms. Dusty atmospheres were prevalent during cutting and loading operations. No means are used to allay this dust.
Dust samples collected during the previous inspection indicated that additional rock dusting was required. No samples were collected during this inspection; additional rock dusting has not been done, so the condition is unchanged.
*1. Water or a wetting solution should be applied to the cutter bars of mining machines and the loading heads of conveyors to allay the dust.
*2. All open, unsealed places in the mine should be thoroughly rock-dusted to within at least 40 feet of the faces so that the incombustible content of the resultant dust will be 65 percent plus an additional 1 percent for every 0.1 percent of methane in the mine air.
*3. Dust accumulations should be loaded into cars and removed from the mine.
HAULAGE The surface haulage tracks are well maintained. However, frogs, switches, and guardrails are not blocked; some of the switches are not equipped with switch throws. This also applies to conditions underground. Car droppers do not wear safety belts when handling railroad cars at the tipple, as previously reported.
Haulage roads throughout the mine are generally dirty. Clearance is inadequate and shelter holes are not provided. A clearance of 12 inches is being maintained on the trolley wire side as recommended.
Cars are still being pushed and trip riders ride on the front end of trips. Trip riders also jump on and off moving trips. As previously reported, no trip lights are used, and tocomotives are not equipped with gongs and do not carry jacks or other suitable rerailers.
Men continue to ride on the trolley wire side of man-trips, and some employees were noted leaving the trip before it came to a full stop.
1. Track switches on the surface and underground should be complete with switch throws; the rod extending from the bridle bar to the throw should be covered so as to eliminate stumbling hazards.
2. Frogs, switches, and guardrails should be blocked; this applies to surface and underground.
3. Car droppers handling railroad cars at the tipple should wear safety belts. 4. Haulage roads should be kept free of coal spillage and debris.
5. On all haulage roads, there should be a continuous clearance on the side opposite the power wires of at least 30 inches between the nearest obstruction to the farthest projection of any moving equipment.
* 6. Shelter holes should be provided along áll haulageways on the clearance side at 60-foot intervals. Crosscuts properly cleaned out are suitable.
* 7. Pushing cars or trips should be eliminated insofar as possible; no trips should be pushed on main haulageways, except at partings or in an emergency.
* 8. Trip riders should be prohibited from riding on the front bumpers of pushed trips, and from jumping on and off trips while they are in motion.
* 9. A permissible trip light should be used on the rear of all trips and on the front end of cars being pushed.
* 10. Locomotives should be equipped with warning gongs and should carry jacks or other suitable rerailers.
11. Men should not ride on the trolley wire side on man-trips.
ELECTRICAL EQUIPMENT, ACCESSORIES, AND HAZARDS No major changes have been made in the electrical system and equipment since the previous inspection. A dead-front switchboard has been provided for the 2,300-volt generator on the surface; so, guarding the front of the board is unnecessary.
As previously reported, the underground motor-generator substation was not equipped with fireproof doors.
Telephone lines are installed in many places on the same side of the entry as power wires, and in some instances, they are in contact with bare feeder lines. This is a hazardous condition, since the telephones are not equipped with fuses and the casings are not grounded. Nips on cutting machines, loading machines, drill and locomotive cables are not equipped with fuses. Trollet wires are not guarded at all places where men are required to pass under them. The trolley lines are not sectionalized or guarded at man-trip stations.
The frames of mining machines, loading machines, and electric drills, are not grounded, and no fuse protection is provided for the mining and loading machines.
Temporary cable splices are made with splicirig rings, and covered with friction tape. These splices appeared mechanically and electrically strong, but they are considered permanent.
The thread bars of electric drills have been fully guarded, an improvement since the previous inspection.
Permanent pump installations are not housed in fireproof rooms, and the wiring is poorly installed. No fire protection is provided. The frames of the pump motors, however, have been grounded.
All electrical equipment underground is of the nonpermissible type.
1. The underground substation should be equipped with fire doors arranged to close automatically in case of fire.
* 2. Telephone lines should be installed on the side opposite the power wires, and the telephones should be equipped with fuses and ground connections.
* 3. Nips of mining machines, loading machines, drill and locomotive cables should be equipped with fuses.
* 4. Trolley wires should be sectionalized at man-trips stations, and the power should be cut from the line when men load and unload. In addition, the trolley wire should be guarded, at these stations.
* 5. Trolley wires less than 612 feet above the rail should be guarded at all places where men are required to pass under them.
* 6. The frames of mining machines, loading machines, and electric drills should be grounded.
7. Proper fuse protection should be provided for mining and loading machines.
8. Permanent cable splices should be made by competent persons in underground or surface repair shops ; splices should preferably be vulcanized.
9. Permanent pump installations should be in fireproof rooms.
10. Wiring for pump installations should be properly installed on insulators, and proper fuse protection should be provided.
11. If possible, permissible junction boxes should be used in making connections at the working faces.
*12. The use of nonpermissible electrical equipment in the face regions requires that each working place be carefully examined for gas immediately before the equipment is taken into or operated in the place, and at least every 30 minutes while the equipment is in the face. The general air of the place should not contain more than one-half of 1 percent methane, and if more than 1 percent methane can be found in cavities in the roof, the equipment should not be taken into or operated in the place until the pocket of gas has been removed by additional ventilation.
13. Any replacement of equipment, so far as feasible, should be of permissible type.
SAFEGUARDING MECHANICAL EQUIPMENT The cutter chains of mining machines were not equipped with locking devices or guarded when machines were being moved. Also, the belt and gear drives on pumps were not guarded.
The V-belt drive on the shaker-screen motor was still not guarded. Also, the various gear and belt drives in the shop have not been equipped with guards.
All hand tools observed were in good condition.
1. Mining machines should not be loaded on their trucks or moved unless they are equipped with adequate locking devices for the cutter chains, and the exposed bits at the cutter bar should be guarded or removed.
*2. All belt and gear drives in the tipple and shop should be guarded.
UNDERGROUND FIRE PREVENTION Fire extinguishers and dry sand in containers are provided at the underground substation. No other improvements have been made in fire-fighting facilities.
Oil is stored in 50-gallon drums in open crosscuts and room necks.
1. Adequate fire-fighting facilities should be provided at strategic locations underground.
*2. Underground storage places for oil and grease should be of fireproof construction.
*3. Oil and grease kept in face regions or other working locations should be in portabil, closed metal containers.
The emergency escapeway in the air shaft is a well-maintained and properly railed stairway. Signs indicating the way of escape are posted.
The system of checking men into and out of the mine does not provide a positive means of identifying the personnel underground.
All of the employees use carbide lamps, and smoking underground is permitted; both are fire and gas ignition hazards.
About 90 percent of the men wear hard hats, and about 80 percent wear safety. toe shoes. No goggles were observed.
*1. A check-in-and-out system should be adopted that will provide positive identification, upon the person of every individual underground. An accurate record of the men in the mine should be kept in a place that will not be affected in the event of an explosion.
*2. All employees should use permissible electric cap lamps, and smoking in the mine should be prohibited.
*3. All employees should wear safety-toe shoes; safety hats should be worn by all underground employees and also surface employees doing work where there is danger from falling objects.
*4. Goggles should be worn by all employees doing work where particles are likely to fly.
GENERAL SAFETY CONDITIONS No safety organization is maintained, and no safety inspector is employed. Following is the company's accident experience for 1942 and 1943 :
TABLE 2.- Fatal- and nonfatal-injury data
Per million man-hours.
Per million tons of coal. Days lost (including fatalities).
35.0 303, 212.0 321, 860.0
400 433, 37. 430, 0480
115. 43 108. 74 1, 190. O
97.65 12. 471.0
The majority of accidents including the two fatalities in 1943 are the results of roof falls. This indicates the necessity of closer supervision on roof control and emphasizes the need for systematic timbering and strict enforcement of the rules.
No mine-rescue or first-aid training has been given since the previous inspection.
There are no gas masks or other rescue apparatus available at the mine; a fully equipped State-owned station is 40 miles from this operation.
1. A safety organization of men and officials should be established; and joint safety meetings should be held at least monthly.
2. A safety inspector should be employed.
3. At least 12 men should be trained in mine-rescue work, and, if possible, additional training should be given monthly.
4. All employees should be given first-aid training annually. 5. At least six gas masks and accessories should be available at the mine.
SUMMARY OF SAFETY IMPROVEMENTS The following important safety improvements were due to various influences such as recommendations of Federal coal-mine inspectors, orders and suggestions of State mine inspectors, initiative of mining company officials, cooperation of miners individually and collectively, or the safety efforts of other groups.
1. Records are being kept of the daily inspection of hoisting equipment, including ropes and shea ves.
2. Positive stopblocks have been provided at the surface landing.
5. “Danger” signs have been properly posted at the explosives-storage magazine, and two five-tumbler padlocks are used to secure the door.
6. Falls in air courses have been cleaned.
8. Fire bosses and face bosses are provided with permissible flame safety lamps.
9. A clearance of 12 inches is being maintained on the trolley wire side of entries.
10. A dead-front switchboard is provided for the 2,300-volt generator on the surface.
11. The thread bars of drills are fully guarded. 12. Pump motor frames are grounded.
F. J. GALLAGHER, Coal-Mine Inspector.
(U. S. Department of the Interior, Bureau of Mines)
REINSPECTION No. 2 Company: ('entralia ('oal Co. Mine : No. 5. Location: Centralia, Marion County, Ill. Date of inspection : June 5-6, 1944. Inspectors: F. J. Gallagher and C. F. Kahre. Number men employed : 226. Daily production : 1,900 tons.
The facts disclosed by the inspection of this mine, including both commendable conditions and practices and those that should be corrected, will be embodied in a detailed report to be made available to the public in accordance with the Federal Coal Mine Inspection and Investigation Act of 1941, H. R. 2082.
The purpose of this preliminary report is to point out good features as well as certain unsafe practices and conditions that should be corrected promptly.
The volume of air at the intake was 61,000 cubic feet a minute, which is sufficient for present needs. The air was measured in all working entries and was found to be sufficient, except in 21 and 22 south off 4 west entry, where it was found to be inadequate due to leaky wooden stoppings and doors erected singly.
Entry stoppings should be constructed of incombustible material and kept as nearly leakproof as possible.
Doors should be erected in pairs to form air locks, but in no event should they be provided with latches.
A minimum of 6,000 cubic feet of air a minute should pass through the last open crosscut in 21 and 22 south off 4 west.
The mine is recognized as gassy; however, no gas was detected by means of a permissible flame safety lamp during this inspection.
Air samples were taken and will be analyzed in the Bureau of Mines laboratory, and the results will be published in the final report. Permissible flame safety lamps are used in testing for gas, a commendable improvement.
No method is used to control coal dust at this mine. Large accumulations of coal dust were observed along haulage roads in rooms and at the discharge ends of loading conveyors.
All accumulations of coal dust should be loaded into cars and removed from the mine.
It is recommended that water or a wetting solution be applied to the cutter bars of mining machines, loading prints of all conveyors, and on all loaded cars.
Dust samples collected during the previous inspection indicated that additional rock dust was needed in some areas.
Rock dust is not applied close enough to the faces of entries and no rock dust is used in rooms.
All open unsealed places in the mine should be thoroughly rock-dusted to within 40 feet of the faces.
No samples were collected because the condition is unchanged since the previous inspection; no additional rock dust has been used.
Permissible explosives, primed with cap and fuze, are used to blast the coal. Fuze is ignited by carbide lamps.
No tests for gas are made before or after firing.
Shots should be fired by electric detonators of proper strength, and a permissible shot-firing unit should be used.
Tests for gas should be made before and after blasting.
ELECTRICAL EQUIPMENT, WIRING, AND GUARDING The electrical equipment is of the nonpermissible type, however, it appears to be in good operating condition. Telephone wires at several places are on the same side of the entry as the power wires. Nips on cutting machines, drills, Joy loading machines, and locomotive cable are not equipped with fuses, and the trolley wires are not guarded at several places where men are required to pass under.
Telephone wires should be on the opposite side of the power wires throughout the mine.
All trailing cables on cutting machines, drills, Joy loading machines, and locomotives should be provided with fuses.
Trolley wires should be guarded where men are required to pass under them.