« AnteriorContinuar »
The trolley wire and power cable along the new 1 west south haulageway have been supported securely on insulated hangers. The trailing cables of the portable electric equipment in the 18 and 19 north section of the mine have been provided with taps equipped with fuses, but the fuse taps are not of a suitable type because they are not insulated and present shock hazards. The room housing the motorgenerator set at 20 north off 4 west south is not fireproofed fully. Telephones are not provided within about 4,000 feet of the working sections.
1. All cables for portable underground electric equipment should be provided with suitable insulated taps equipped with fuses.
2. The room housing the motor-generator set at 20 north off 4 west south should be fireproofed completely.
3. Telephone service should be provided from the surface to within several hundred feet of the working sections. Repeated recommendations
1. The frames of underground portable electric equipment should be provided with separate grounding circuits.
2. The insulators supporting the power wires along the 4 west south haulageway should be spaced not more than 30 feet apart, and the wires should be kept taut and not permitted to touch the roof, ribs, cross bars, or door frames.
3. The power wires along the 21 south haulageway should be installed on the same side as the trolley wire.
4. The ends of trolley or bare power wires should not be extended into rooms that are not ventilated properly.
5. The trolley and power wires should be guarded properly on each side of ventilation doors, and at all places where persons are required to work or pass under the wires.
6. Guards should be placed along the trolley wire at the man-trip stations, and provisions should be made to deenergize the wire while man-trips are being loaded and unloaded.
7. The mining machines and loading machines should be protected against excessive overload by fuses or equivalent protective devices of the correct type and capacity.
8. The telephone lines along the 4 west south haulageway should be installed on the opposite side from trolley or power wires.
9. The permanent pump installations should be in well-ventilated fireproof
10. Any replacement of electric equipment that is to be used in the face regions should be of permissible type.
11. Each machine man should be instructed in the use of and provided with a permissible flame safety lamp. Tests for gas should be made immediately before the nonpermissible mining machines and loading machines are taken into working places, and tests also should be made at intervals of 30 minutes or less while electric equipment is being used in the working faces.
10. ADDITIONAL SAFEGUARDS FOR MECHANICAL EQUIPMENT Repeated recommendations
1. The propelling chains of mining machines should be guarded adequately, the cutter chains should be equipped with adequate locking devices, and the exposed bits at the ends of the cutter bars should be removed or guarded before the machines are trammed.
2. All machinery drive belts and gears exposed to possible personal contact in the surface and underground shops, tipple, and steam plant should be guarded adequately.
11. UNDERGROUND FIRE PREVENTION AND CONTROL Accumulations of waste paper were noted at a number of places in the mine.
1. The accumulations of waste paper should be removed from the mine, as they constitute a fire hazard. Repeated recommendations
1. Bags of rock dust should be placed on the intake side of ventilation doors, and fire extinguishers approved for electrical fires should be provided on each locomotive, mining machine, and loading machine.
2. Underground storage places for lubricating oil and grease should be of fireproof construction, and lubricating oil and grease kept in face regions or other working locations should be in portable, closed, metal containers.
1. The locations of telephones, power lines, and ventilation doors should be indicated on the mine map.
2. Direction signs should be posted conspicuously to indicate the designated escapeway.
3. The gate at the surface opening to the escapement shaft stairway should be kept locked to prevent unauthorized persons from entering the mine, but the gate should be locked in such a way as not to prevent the escape of employees in an emergency.
4. Only permissible electric cap lamps for illumination should be carried by all persons in the mine.
5. In addition to the present method of checking men into and out of the mine, a metal identification check should be fastened to the belt of each employee.
6. The practice of smoking underground should be prohibited and discontinued. Employees should be searched frequently enough to assure that smokers' materials and matches or other lighting devices are not carried into the mine.
7. Safety hats should be worn by all employees on the surface doing work where there is danger from falling objects, and safety-toe shoes should be worn by all employees, officials, and others while on duty in and around the mine.
8. Haulagemen and others who work around machinery should wear snugly fitting clothing and have trouser legs tucked inside socks or otherwise fastened.
9. Men should wear goggles or eye shields when exposed to hazards of flying particles.
13. GENERAL SAFETY CONDITIONS All of the underground officials except the mine examiner for the night shift now are certified.
1. The mine examiner for the night shift should hold a certificate of competency issued by the Illinois Department of Mines and Minerals. Repeated recommendations
1. The section foremen should record in ink the results of their daily inspections in a book kept on the surface for that purpose; it should be dated and signed by the section foremen and countersigned by the mine foreman.
2. All entrances to abandoned places should be fenced properly, and suitable “Danger" signs should be posted on the fences to warn persons of possible hazards.
3. A safety engineer or safety director should be employed at this mine, and a safety organization of employees and officials should be established.
4. A safety committee including workmen and officials should make periodic inspections of the mine and submit recommendations for correcting hazards observed.
5. The employees should be included in the monthly safety meetings that are being held by the officials. 6. Additional first-aid training should be given to all employees annually.
7. The men at the mine who have been trained in mine rescue work should be given additional training monthly.
14. SAFETY IMPROVEMENTS The following recent safety improvements were observed during this inspection :
1. All of the flame safety lamps now in use in the mine are of permissible type, and they are kept in permissible condition.
2. Two efficient electric lights have been installed at the ground landing to the shaft so as to provide adequate illumination for men getting on and off the cages.
3. Four additional 242-gallon fire extinguishers have been provided for the surface buildings.
4. A safety rule has been established prohibiting shot firers from bringing explosives to or near a face while electric equipment is at the face.
5. About 500 feet of the main intake air course near the shaft bottom has been cleaned free of roof falls.
6. The mine examiners now carry permissible electric cap lamps in conjunction with their permissible flame safety lamps.
7. The work of welding angle irons around the openings of endgates of the mine cars has been completed, and the cars were maintained reasonably dusttight.
8. The low roof at the 4 west south passing track has been removed and the trolley wire has been raised and placed about 6 inches outside the rail so as to provide adequate clearance for haulage units.
9. The trolley wire and power cables along the 1 west south haulageway have been supported securely on insulated hangers.
10. The power cables in 22 south have been removed from under the falls of roof and have been supported securely on insulated hangers.
11. The ends of trolley or power wires were not extended beyond the last open crosscuts.
12. Well-constructed guards have been provided for cutting shears and drillpress drive belts in the shop on the surface.
13. The underground fire-fighting equipment has been supplemented with six additional 242-gallon soda-acid-type fire extinguishers.
14. Ninety-five percent of the underground employees now wear safety-toe sboes, an increase of 15 percent.
15. All of the section foremen now hold certificates of competency issued by the Illinois Department of Mines and Minerals.
16. The bulletin boards are cleaned frequently, and they were clean at the time of this inspection.
ACKNOWLEDGMENTS The cooperation of the State mine inspector, company officials, and employees during the inspection is gratefully acknowledged.
The prevention of accidents requires cooperation between officials and employees, and such cooperation can only be attained when facts concerning hazards are known. It is hoped, therefore, that the facts in this report will help in pre venting accidents at this mine. Respectfully submitted.
FRANK PERZ, Coal-Mine Inspector.
(U. S. Department of the Interior, Bureau of Mines) Company: Centralia Coal Co. Mine: No. 5 mine, Location: Centralia, Marion County, Ill. Date of inspection : March 5-8, 1946. Inspector: Frank Perz. Number of men employed : 251. Daily production : 1,964 tons. Originating office: Bureau of Mines, 201 Post Office Building, Vincennes, Ind.;
C. A. Herbert, supervising engineer.
The facts disclosed by the inspection of this mine, including both commendable conditions 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.
VENTILATION The mine is ventilated by means of a reversible-type fan located underground, and was delivering 58,880 cubic feet a minute. The air is directed to the working sections in one continuous current and is controlled by means of concrete, wooden, and fire-resistant stoppings. Two sets of air-lock doors are installed, but all other doors in the mine are erected singly.
The rooms throughout the mine are driven 400 feet in depth, and the only room crosscuts that were closed were those between No. 1 and No. 2 rooms off 13 north; consequently, the faces of the rooms in the other working entries were not ventilated adequately.
Four of the five crosscuts between the face of the 1 and 2 west south entries and the first outby permanent stopping were closed with poorly constructed check curtains.
1. The present fan, or a new fan of adequate size and capacity to ventilate the mine properly, should be installed on the surface in a fireproof housing, at least 25 feet from the nearest side of the mine opening, and installed so as to permit the reversal of the air flow.
2. Stoppings between the intake and return air of all main haulageways should be constructed of substantial incombustible material, and, on branch haulageways, stoppings should be constructed of incombustible or fire-resistant material.
3. Doors used in connection with coursing the air should be erected in pairs to form air locks; where the system of mining does not permit this, tight check curtains, well maintained, should be hung in connection with single doors.
4. Room crosscuts should be closed where necessary to obtain a perceptible movement of air at the face to remove smoke, explosives fumes, and dust.
5. Stoppings should be completed promptly as the passageways are advanced.
AIR AT WORKING FACES
The quantity of air passing through the last open crosscut in five out of six pairs of working entries was found to be adequate, as the air measurements obtained ranged from 6,800 to 21,240 cubic feet a minute. No air measurement could be obtained in the last open entry crosscut between 1 and 2 west south.
1. The quantity of air reaching the last open crosscut in each pair of working entries should be at least 6,000 cubic feet a minute.
The mine is classified as gassy by the Bureau of Mines, but it is not operated in full compliance with the recommendations of the Bureau of Mines for a mine so classified. Methane was not detected by means of a permissible flame safety lamp during this inspection. However, the results of the analyses of air samples collected during the previous inspection disclosed sufficient methane to warrant classifying the mine as gassy.
The mine examiner for the day shift begins the preshift examination of the mine at midnight, or about 7 hours before the shift enters the mine, and the preshift examination for the night shift is made immediately prior to the time the night shift enters the mine. The mine examiners mark the date of the inspection near the face of most of the rooms and entries visited, but very few dates were found at the face of crosscuts. Each working place is inspected for safety several times during the working shift by a certified official, but tests for gas are not made during these inspections.
1. This mine, which is classed as gassy by the Bureau of Mines, should be operated in full compliance with Bureau of Mines recommendations for a mine so classified.
2. The preshift examination of the mine should begin not more than 3 hours before the shift enters the mine, and the mine examiners should mark their initials and the date at or near the face of each place examined.
3. The section foremen should be provided with permissible flame safety lamps, and tests for gas should be made in every working place visited by them; the results of these inspections should be recorded in ink in a book kept on the surface for that purpose.
CONTROL OF COAL DUST
No method of allaying dust is used in this mine. Most of the mine is very dry and an extremely large amount of coal dust is thrown into suspension during cutting, loading, and transportation operations and during dumping operations at the shuttle car transfer stations. These dusty conditions present a serious dust-explosion hazard, and also present a hazard to the mining-machine and loading-machine operators, because their vision is obscured by clouds of dust while the machines are in operation. Large accumulations of fine coal and coal dust were present on most of the main and intermediate haulage roads and on the roadways and gob areas in the working places.
1. Water or a wetting solution should be used to allay the coal dust on the cutter bars of mining machines, on the coal pile before and during loading, on the haulage roads, and on the discharge end of the shuttle cars while transfering coal into mine cars.
2. The fine coal and coal dust on the haulage roads should be loaded into cars and removed from the mine as soon as possible, and regular cleaning schedules should be arranged to prevent dust from accumulating in the future. The loose coal and coal dust on the roadways and gob areas in the working places should be cleaned systematically as the working places advance.
No rock dusting has been done in this mine since the July 1945 inspection, Samples of dust were collected at various locations in the mine and will be analyzed in the Bureau of Mines laboratory. The results of these analyses will be recorded in the final report.
1. This mine should be rock-dusted thoroughly in all open, unsealed places to within 40 feet of the faces so that the incombustible content of the resultant dust will be at least 65 percent, plus 1 percent for each 0.1 percent of methane present in the ventilating current.
EXPLOSIVES Permissible explosives, fired by different lengths of fuze and No. 6 blasting caps, were used for blasting. Examinations for gas are not made immediately before shots are fired; however, the mine examiner tests for gas before any work is resumed after blasting. Shots are fired in rapid succession at the end of the shift while all of the men are in the mine.
1. Permissible explosives should be fired only with instantaneous electric detonators of proper strength and permissible shot-firing units.
2. Examinations for gas should be made in the blasting area immediately before blasting.
3. Shots should be loaded and fired singly unless they are fired simultaneously and in full compliance with the Bureau of Mines recommendation for permissible blasting
ELECTRICAL EQUIPMENT, WIRING, AND GUARDING The electrical equipment is of the nonpermissible type, and inspections for gas are not made before the equipment is taken in by the first open crosscut of the working places.
The trolley wire and feeder cable along the 1 west south haulageway are installed properly on insulated hangers, but the power wires along some of the other haulageways were not kept taut and were observed contacting timbers and the rib. The power wires are not insulated where they pass through doors and stoppings, and the trolley and power wires are not guarded at crossings, doors, and man-trip loading and unloading stations.
1. Any replacement of electrical equipment to be used in face regions should be of permissible type.
2. Each workiug place should be inspected carefully for methane by a certified official or other competent person immediately before electrical equipment is taken in by the first open crosscut or operated in a working place.
3. The trolley and power wires should be kept taut and not permitted to contact the roof, rib, or timbers.
4. The power wires should be insulated properly where they pass through doors and stoppings.
5. The trolley and power wires should be guarded properly at all places where persons are required to pass under the wires, on each side of ventilation doors, and at the man-trip loading and unloading stations.
TIMBERING A standard plan of timbering has not been adopted. However, considerable improvement has been made in timbering the gob areas in the working places since the previous inspection. Two rows of posts are set on each side of the track on 4 to 5-foot centers to within about 10 feet or less of the working faces, but safety posts are not used near the working faces.
Considerable unsupported loose roof and pots were observed along the roadways and at the faces of a number of working places, and unsupported overhinging brows exist along most of the haulageways.
1. Methods of systematic face timbering suitable to the roof conditions in this mine should be adopted and a plan thereof posted, the timbering method should be enforced.
2. Temporary safety posts, jacks, or cross bars should be set near the working faces before other mining operations are begun.
3. Loose roof and pots, and overhanging brows in places where men are required to work or travel should be removed or supported as soon as detected, and no person should be under such loose material until it is made safe.