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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.

MINE GASES

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.

ROCK DUSTING

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 working place should be inspected carefully for methane by a certified official or other competent person inmediately 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.

HAULAGE-ROADWAYS, ETC. The 1 west south haulage road was clean, but large accumulations of coal spillage and debris are present on most of the other haulage roads. The clearance side along most of the haulage roads in the mine is obstructed by road cleanings and gob material, and only a few shelter holes are provided along the haulageways. Small boards are used on the rear end of trips instead of trip lights, and trips of cars are pushed a long distance on intermediate haulage roads.

1. Haulage roads should be kept free of coal spillage and debris.

2. There should be a continuous clearance on the side opposite the trolley wire, from the shaft bottom to all working faces, of at least 30 inches from the nearest obstruction to the farthest projection of moving equipment.

3. Clearance along haulageways should not be obstructed by road cleanings, gob, rock, and other materials.

4. Shelter holes should be provided along all haulageways at 60-foot intervals.

5. Permissible electric trip lights should be used on the front of all trips pushed and on the rear of all trips pulled.

6. Pushing of cars should be eliminated insofar as possible; trips should not be pushed on main haulageway's except at partings or in an emergency.

LIGHTING

All of the underground employees and officials, except the superintendent and the mine examiners, use open-flame carbide lights for illumination.

1. Permissible electric cap lamps should be carried by all persons for illumination in the mine.

UNDERGROUND- GENERAL

All of the underground employees wear safety hats, and 95 percent of the men wear safety-toe shoes; this is a considerable improvement in the number of men wearing safety-toe shoes. Haulagemen and men working around machinery wear loose-fitting clothing. The failure of men to wear goggles or eye shields when doing work that required their use resulted in 13 lost-time eye injuries during the year 1945. Smoking is permitted in the mine.

Accumulations of waste paper were noted at a number of places in the mine.

1. Safety-toe shoes should be worn by all employees and others while on duty in and around the mine.

2. Ha ulagemen and others who work around machinery should wear snugly fitting clothing and have trouser legs tucked inside socks or otherwise fastened.

3. Men should wear goggles or eye shields when exposed to hazards of flying particles.

4. The practice of smoking in the mine should be prohibited, as it presents a definite gas-ignition and fire hazard.

5. The accumulations of waste paper should be removed from the mine, as it constitutes a fire hazard.

SURFACE HAZARDS

A wetting solution is used to allay the coal dust at the dumping point in the tipple; however, it does not appear to be very effective as considerable coal dust was in suspension during dumping operations. The open-type electric motors and starting switches in the tipple have not been replaced with motors of dust-tight construction, and provisions have not been made to remove the coal dust from the floors and the motors in the tipple regularly.

Well-constructed guards have been provided for the cutting shears and drill press drive belts in the shop on the surface, but a number of machinery drive belts in the surface and underground shops, and several sprockets and gears in the tipple are still unguarded.

1. The coal dust in the tipple should be removed by an air exhaust system with dust-collecting hoods placed at principal sources of dust.

2. The open-type electric motors and starting switches in the tipple should be replaced with motors and starting switches of dust-tight construction.

3. The coal dust should be removed from the tipple thoroughly every day, and where it is impracticable to remove coal dust from remote places, such places should be rock-dusted thoroughly.

4. The machinery drive belts in the surface and underground shops should be guarded properly, and the exposed gears and sprockets in the tipple should be guarded completely.

CAGES AND OTHER HOISTING EQUIPMENT Two efficient electric lights have been installed at the ground landing to the shaft so as to provide adequate illumination for the men getting on and off the cages; this is a commendable safety improvement.

The sides of the cages are not enclosed fully, and safety gates are not provided across the open ends ofthe cages when men are hoisted and lowered.

1. The sides of the cages should be enclosed fully, and safety gates should be provided across the open ends of the cages when men are hoisted or lowered.

GENERAL COMMENTS

The company does not employ a safety director. A safety organization was not maintained ; consequently, no safety meetings were held.

1. A safety director or safety engineer should be employed at this mine.

2. A safety organization of employees and officials should be established and joint safety meetings should be held at least once a month to discuss accidents and unsafe practices, and to devise ways and means of preventing accidents.

The State mine inspector, officials, and employees extended full cooperation and assistance during the inspection.

FRANK PERZ, Inspector.

[Note.—This release is issued by direction of the Federal Coal Mine Inspection Act of

May 7, 1941 (Public Law 49, 77th Cong. ]

DEPARTMENT OF THE INTERIOR

INFORMATION SERVICE

BUREAU OF MINES

[For release June 5, 1946)

CENTRALIA, ILL., COAL MINE INSPECTED In reviewing safety conditions observed recently at the Centralia Coal Co.'s No. 5 mine, at Centralia, in Marion County, ill., a Federal coal mine inspector has offered numerous recommendations designed to increase protection for life and property, the Bureau of Mines disclosed today in releasing a detailed safety summary. The mine employed 251 men and averaged 1,964 tons of coal daily when it was visited some weeks ago by Inspector Frank Perz.

Bureau analyses of air samples again disclosed sufficient explosive gas to warrant a "gassy” rating. Perz said in suggesting compliance with Bureau standards for "gassy" mines, including approved preshift examinations, tests for explosive gas before and after blasting, and before and during the operation of nonpermissible electrical equipment underground, replacement of openflame cap lamps with permissible electric cap lamps, and a ban on smoking in the mine.

Although Inspector Perz cited some improvements effected since a previous inspection in July 1945, he emphasized the need for more corrective measures, among which were more extensive timbering under a systematic plan, frequent roof testing in an approved manner, safer storage and handling of blasting supplies, added precautions when multiple blasts are practiced, more effective face ventilation, and consideration of a split system of air coursing throughout the mine, control of coal dust, elimination of unsafe haulage practices and substandard conditions, frame grounds and other safeguards for electrical equipment, guards or shields for exposed mechanical equipment, universal wearing of safety apparel, joint safety meetings of workers and officials, annual training of employees in first-aid methods, and retraining of mine-rescue crews.

Among recent betterments cited by the inspector were exclusive use and good maintenance of permissible flame safety lamps for gas testing, adequate illumination at the shaft landing, deenergizing of electrical equipment before explosives are taken to faces, removal of roof falls from part of the main intake air course, wearing of permissible electric cap lamps by the mine examiners, insulated supports for some trolley wires, safer installation of some power cables, guards for exposed shop equipment, increased underground fire protection, additional employees wearing safety-toe footwear, and State certification of section foreman.

Beneficial changes at the No. 5 mine were attributed to company initiative, employee cooperation, compliance with orders of State inspectors, and adoption of Bureau recommendations.

Copies of the report are available for inspection at the Bureau of Mines, Department of the Interior, Washington, D. C., and at the Bureau of Mines district office at Vincennes, Ind.

COAL-MINE INSPECTION REPORT, NO. 5 MINE, CENTRALIA COAL CO.,

CENTRALIA, MARION COUNTY, ILL., NOVEMBER 4-6, 1946

(By Frank Perz, coal-mine inspector)

INTRODUCTION This report is based on an inspection made in accordance with the Coal-Mine Inspection and Investigation Act of 1941, Public Law 49, Seventy-seventh Congress, H. R. 2082, and the terms of the agreement of May 29, 1946, between the Secretary of the Interior, acting as Coal Mines Administrator, and the United Mine Workers of America.

The purpose of this report is to inform the Coal Mines Administrator and other persons concerned of violations of the Federal Mine Safety Code, and to suggest means of correcting hazards.

The application and enforcement of State laws and rules or regulations made pursuant to such laws are in no manner affected by the Federal Mine Safety Code. Compliance with the Federal Mine Safety Code in no way excuses noncompliance with State laws and rules or regulations made pursuant thereto.

GENERAL INFORMATION A new superintendent, H. C. Niermann, of Centralia, Ill., is in charge of the mine. The No. 5 mine is located 2 miles south of Centralia, Marion County, nu. It is opened by two wood-lined shafts and is developed in the Illinois No. 6 coal bed, which averages 76 inches in thickness in this mine. A total of 266 men was employed, of which nuinber 160 worked underground on the day shift, and 48 on the night shift. The average daily production was 2,159 tons of coal. All coal was undercut by means of shortwall mining machines and was loaded mechanically by means of mobile-loading machines. The mine management stated that the life of the mine at the present rate of production was estimated to be 16 years.

Bureau of Mines sampling has shown gas to be present in excess of 0.25 percent during previous inspections.

VIOLATIONS OF FEDERAL MINE SAFETY CODE

ARTICLE I. SURFACE STRUCTURES

Section 10.-Dense clouds of coal dust were present at the open-type electric motors throughout the tipple.

In dusty locations, motors of dust-tight construction should be provided, or the present motors should be corrected with reasonably dust-tight housings. Section 10.-Excessive accumulations of coal dust were present throughout the tipple.

The tipple should be kept free of coal-dust accumulations. Section 3a.The opening in the floor at the discharge end of the raw-coal conveyor in the tipple was not provided with railings.

The opening in the floor at the discharge end of the raw-coal conveyor in the tipple should be provided with railings.

ARTICLE III. TIMBERING Section 1a.The timbering system adopted at this mine was not being carried out in a number of working places in the 13 north and 14 north sections off 1 west south.

The minimum standards of timbering should be complied with in all working places in the mine. Section 20.-Timbers of sufficient length to use as cross bars were not provided in the working sections.

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