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and revision may be with respect to its general application, its application to types, conditions, and methods of mining and mines, or its application in specific

Such review and revision shall be made whenever appropriate to carry out the intent and purposes of the agreement between the Secretary of the Interior, acting as Coal Mines Administrator, and the United Mine Workers of America, dated May 29, 1946, requiring a reasonable code of standards and rules pertaining to safety conditions and practices in mines. Pending review and revision, as herein provided, the Coal Mines Administrator may suspend or stay, for such periods as he deems reasonable, the provisions of this code as applied to any mine or mines when such suspension or stay is necessary, in his opinion, to carry out and comply with the purposes and provisions of Executive Order 9728 or in order to avoid irreparable damage or great injustice pending review and revision of specified provisions of the code.

ARTICLE XV-COMPLIANCE WITH CODE

SECTION 1. Compliance with code.-a. Whenever any equipment or supplies required by this code, including rock-dusting machines, flame safety lamps, and permissible electric equipment, are unobtainable, compliance with the requirements of this code with respect thereto is suspended to the extent that such items remain unobtainable until they are obtainable. Due allowance shall also be made for planning, institution of changed procedures, and installation of new equipment.

0. Compliance with the requirements of this code shall be started promptly and prosecuted diligently until the provisions of the code have been fulfilled.

R. R. SAYERS, Director, Bureau of Mines. Approved :

J. A. KRUG, Secretary of the Interior. Mr. FORBES. The Federal Mine Safety Code is used as a basis for determining unsafe conditions and practices in bituminous coal and lignite mines in the United States. The Inspection Standards for Anthracite Mines are used as a basis for determining unsafe conditions and practices in anthracite mines in Pennsylvania. And I would like to have inserted a copy of the anthracite safety standards.

Mr. KELLEY. That will be inserted in the record. (The document referred to is as follows:)

S. FETY STANDARDS FOR ANTHRACITE MINES

INFORMATION CIRCULAR 7449, FEBRUARY 1948

(Revision of I. C. 7282)

INTRODUCTION These safety standards for anthracite mines have been prepared for use as a guide for Federal inspectors. They are revision of Tentative Inspection Stand. ards for Anthracite Mines, published as Bureau of Mines Information Circular 7282 issued in May 1944 and used as a guide in Federal inspections. No provision made in these safety standards should be construed or operate to nullify any existing State statutes; they are intended to supplement the State statutes in the interest of increased mine safety. Mines are inspected in accordance with the Federal Coal-Mine Inspection and Investigation Act of 1941, Public Law 49, Seventy-seventh Congress, H. R. 2082. Any unusual hazard noted by an inspector and not covered by these standards will be discussed in the inspection report, and suitable remedial procedure will be recommended.

ARTICLE I. SURFACE STRUCTURES Section 1. Breaker and cleaning plant

(a) Electric switches and controls in breakers and cleaning plants should be enclosed.

(b) Where coal is dumped at or near air-intake openings, reasonable provisions should be made to prevent the dust from entering the mine,

Section 2. Lamp house

(a) Naphtha or other flammable liquids in lamp houses should be kept in approved containers or other suitable dispensers.

(b) Flame safety lamps should be permissible and maintained in permissible condition,

(c) Flame safety lamps should be properly cleaned, examined, and assembled by a qualified lamp attendant or other competent person before each period of use. Lamp assembly should again be checked by the person using it immediately before he enters the mine.

(d) When not in service, methane indicators, flame safety lamps, and electric cap lamps should be in the custody of competent persons responsible for maintenance and testing. Section 3. Stairways, ladders, and platforms

(a) Stairways, elevated platforms, or runways, and openings in floors should be equipped with handrails and with toeboards where necessary.

(b) Ladders should be constructed substantially, anchored securely, wellmaintained, and the rungs spaced suitably and uniformly. Backguards should be provided where necessary.

(c) Where repairs are being made to the plant, proper scaffolding and proper overhead protection should be provided wherever necessary. Section. 4. Houskeeping

(a) Good housekeeping should be practiced in and around mine buildings and yards. Such practices include cleanliness, orderly storage of materials, and the removal of possible sources of injury, such as stumbling hazards, protruding nails, and broken glass. Section 5. Wash houses

(a) Where wash houses are provided, they should be: 1. Provided with showers and an adequate supply of hot and cold water. 2. Kept clean and sanitary. 3. Well illuminated. 4. Provided with suitable cloths lockers or hangers.

5. Kept well heated; if necessary, heating equipment should be guarded against contact hazard.

6. Properly ventilated.
7. Provided with at least two exits.

(b) Sanitary toilet facilities or latrines should be provided in or near each wash house.

(c) Persons using wash houses and toilets or latrines should aid in keeping them in a clean and sanitary condition.

ARTICLE II. MISCELLANEOUS SURFACE CONDITIONS

Section 1. Surface fire prevention

(a) Oil, grease, and similar flammable materials should be stored in closed containers separate from other materials to minimize fire hazards to nearby buildings and the mine. If oil or grease is stored in a building, the building or room in which it is stored should be of fire-resistive material and should be well ventilated.

(b) Tight metal receptacles should be provided for oily waste.

(c) Smoking in or about surface structures should be restricted to places where it will not create a fire or explosion hazard.

(d) Unless structures within 100 feet of mine openings are of fireproof or fireresistive construction, fire doors should be erected at or near the portals or at other effective points in the mine openings to prevent smoke or fire from outside sources endangering men underground. These doors should be tested at least monthly to assure effective operation.

(e) A fire extinguisher or a container of clean dry sand or rock dust should be readily available, and combustible surroundings should be wetted before and after electric or acetylene welding or cutting.

ARTICLE III. TIMBERING Section 1. Timbering system

(a) Methods of systematic timbering suitable to the roof conditions encountered in the separate veins should be adopted at each colliery or mine. These should be considered the minimum requirements, irrespective of the firmness of the roof. Additional timbering should be provided where necessary.

(b) Timbering methods should be complied with by workmen and officials. Section 2. Timber supply and timbering

(a) Adequate supplies of good-quality and ample-size timbering materials should be provided convenient to places of use.

(b) Permanent timbers or props should be stood as soon as the required space is available in working places. Where the nature of the roof or ribs requires their use, temporary props, forepoles, or lagging should be used until permanent props or timbers can be placed.

(c) Loose coal or rock in places where men are require to work or travel should be taken down or supported as soon as detected.

(d) Timbers or props knocked out by blasting or otherwise dislodged should be replaced promptly. However, when necessary, temporary props should be stood until permanent timbers or props are replaced.

(e) Broken and decayed timbers should be replaced promptly.

(f) Only good-quality and ample-size timbering materials should be used. Section 3. Testing of roof, ribs, and face

(a) Officials should examine roof, ribs, and face in working places visited, and the conditions of the roof, sides, and timbering along haulageways and travelways should be inspected. Officials should see that dangerous conditions are corrected promptly.

(b) Face workers and other employees exposed to hazards from falls of roof or coal should examine their places and test roof and ribs thoroughly before beginning work and at frequent intervals during the shift. Dangerous conditions should be corrected before other work is begun.

(c) Workmen and officials should use the sound-and-vibration method when testing roof, ribs, and face.

(d) Before loose roof is taken down, the adjacent roof should be examined carefully and tested properly.

(e) Suitable roof-testing bars should be provided for testing the roof, face, and sides. Conveyors and machines should be stopped while tests are being made.

(f) Where there is danger of coal or rock falling or rolling on a person, it should be taken down or spragged securely. Section 4. Removal of timber

(a) The roof should be examined carefully and tested properly before a safety prop or timber (timber set) is removed ; and, where necessary, an additional safety prop or timber (timber set) should be placed. Section 5. Other safety practices

(a) When loose roof, ribs, or face material is being pried down, a bar of suitable length should be employed and used in a proper manner.

(b) In slopes and in the main haulageways timber legs or props should be hitched into the ribs or walls. Where this is not practicable, substantial guardrails should be placed on, or spacers placed between, the props or legs of timber sets.

(c) Suitable cap pieces should be used atop props where the inclination of the vein will permit their use; the end of a prop or timber leg should be hitched into the bottom.

(d) Where needed in pillar work, break-line props, cogs, or cribs should be erected at the loose ends of pillars and pillar stumps.

ARTICLE IV. EXPLOSIVES AND BLASTING

Section 1. Surface magazines

(a) Separate surface magazines should be provided for the storage of explosives and detonators.

(b) A surface magazine for storing high explosives in amounts exceeding 125 pounds should be:

1. Reasonably bulletproof and constructed of incombustible material or corered with fire-resistive material. If a magazine is so located that it is possible to fire bullets directly through the roof into the explosives, the roof should be made bullet-resistive by material of construction, or by a ceiling that forms a tray containing not less than a 4-inch thickness of sand, or by other methods. 2. Provided with a door or doors constructed of 38-inch steel plate lined with a 2-inch thickness of wood, or of a thinner steel place with a greater thickness of wood at the ratio of 1 additional inch of wood for each 18-inch decrease in the thickness of the steel plate, or of other materials which will make them at least equally fire- and bullet-resistive.

3. Provided with a floor made of wood or other nonsparking material and have no metal exposed inside the magazine.

4. Provided with suitable warning signs so located that a bullet passing directly through the face of a sign will not strike the magazine.

5. Provided with properly screened ventilators.
6. Provided with openings for entrance and ventilation only.
7. Kept locked securely when unattended.
8. Grounded, if constructed of metal or if metal-covered.

(c) Surface magazines for storing black blasting powder or detonators need not be bulletproof, but they should be in accordance with the other recommendations for storing high explosives.

(d) High explosives or black blasting powder in amounts of 125 pounds or less or 5,000 detonators or less should be stored in accordance with Section 1b and lc, or in box-type magazines. Box-type magazines may also be used as distributing magazines when the quantities do not exceed those mentioned. Box-type magazines should be strongly constructed of 2-inch hardwood or 3-inch softwood or other equally substantial material. A metal magazine should be lined with nonsparking material. No magazine should be placed in a building containing oil, grease, gasoline, waste paper, or other highly flammable material, nor should a magazine be placed less than 20 feet from a stove, furnace, open fire, or flame.

(e) Where practicable, permanent explosives-storage magazines should be not less than 200 feet from any vital structure, or from any mine shaft, tunnel, or slope opening to the surface.

(f) A magazine used for the distribution of explosives or detonators on the surface should be built in accordance with the standards for the construction of a storage magazine. The supply kept in a distributing magazine should be limited to not more than 3 days' supply or more than 3,000 pounds of explosives. Explosives and detonators may be distributed from the same magazine if separated by at least a 6-inch substantially fastened hardwood partition or the equivalent.

(g) The area surrounding the magazine for not less than 25 feet in all directions should be kept free of rubbish, dry grass, or other materials of a combustible nature.

(h) If the explosives magazine is illuminated electrically, the lamps should be of explosion-proof type and the „wiring in conduit. The switch should be outside the building.

(i) Only nonmetallic tools should be used for opening any type of explosives container. Extraneous materials, other than blasting supplies, should not be stored in an explosives or detonator magazine.

(j) Smoking, carrying smokers' articles, or open flame should be prohibited in or near any magazine, or while explosives or detonators are being handled. Section 2. Underground transportation

(a) Detonators should be transported in closed nonconductive containers, or in the original unopened containers. Attendants only should be permitted to ride on cages or trips carrying detonators, unless the detonators are in substantial, rigid, nonconductive containers.

(b) Explosives should be transported in suitably constructed explosives cars or boxes, or in the original unopened containers. Attendants only should be permitted to ride on cages or trips carrying explosives.

(c) When explosives and detonators are hauled in the same explosives car or in the same special container, they should be separated by at least a 4-inch substantially fastened hardwood partition or the equivalent.

1. The bodies and covers of special cars should be constructed substantially of nonconductive material.

2. Special containers should be of wood approximately 2 inches in thickness; they should be fully insulated.

3. Trips carrying explosives should not be hauled into or out of a mine within 5 minutes preceding or following man-trips. When traveling with the air current, the explosives trip should precede; if against the air current, the man-trip should precede.

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(d) Explosives and detonators transported underground by belt should be transported under the following conditions:

1. In the original unopened containers or in suitably constructed boxes of nonconductive material,

2. Ample clearance should be maintained between the tops of explosives and detonator containers and the roof, timbers, or other obstructions.

3. Suitable loading and unloading stations should be provided.

4. An attendant and stop controls should be provided at each loading and unloading station.

(e) Explosives or detonators should not be transported on flight or shaker conveyors or by scraper loaders.

(f) Explosives and detonators should not be carried by the same person at the same time. Section 3. Underground storage

(a) Explosives and detonators for use in a working place:

1. Should be kept in separate well-constructed nonconductive boxes or in a well-constructed nonconductive two-compartment box having a securely fastened separating partition of wood not less than 4 inches in thickness.

2. Should be kept in these boxes at safe locations removed from the working faces and at safe distances from electric wires and haulage tracks, and tools or other materials should not be stored with explosives or detonators. In pillar work, the foreman should designate a safe place where explosives should be kept.

3. Should be limited in quantity to as nearly a shift's supply as possible. (b) If underground operation boxes are used, they should be: 1. Of suitable construction. If metal, they should be provided with a lining of nonconductive material.

2. Placed in a crosscut (heading) or abandoned chamber or breast neck at a safe distance from roadways; at least 15 feet from trolley or power wires; and in a dry place.

3. Kept locked at all times, except when explosives supplies are being placed in them or removed.

4. Protected from falls of roof and sides,

5. If detonators are kept in the same operation box with explosives, a 4-inch wooden partition should separate the explosives from the detonators.

6. The quantity of explosives or detonators in an operation box should be limited to as nearly a day's supply as possible.

7. Only nonmetallic tools should be used for opening any type of explosives container. Section 4. Blasting practices

The Bureau of Mines is opposed unalterably to the use of nonpermissible explosives in any form in underground mines. However, if any of these explosives, including black powder in any form or dynamite, are used, special safety precautions should be taken.

(a) Permissible explosives only should be used for blasting coal and should be used as follows:

1. Blasts should be fired only with electric detonators of proper strength. 2. Blast holes should be charged and fired only by certified persons.

3. Blast holes should be placed properly, and they should be cleaned before being charged.

4. Blast holes should be stemmed adequately. 5. Only wooden tamping bars should be used.

6. Electric power should be cut off equipment and trailing cables before explosives are taken to the face, and the electric power should remain off until blasting has been completed and the working place examined carefully.

7. Primers should be prepared immediately before loading, in a place removed from tracks, trolley wires, power lines, trailing cables, pipe lines, steel ropes, and conveyor pans, and at or near the face, where feasible.

8. Leg wires of electric detonators should be kept short-circuited until ready to connect to the blasting circuit.

9. Mixed charges should not be placed or fired in any blast hole.

10. The use of mudcap or other open, unconfined shots should be restricted to battery starting when no gas or fire hazard is present and only when it is other: wise impracticable to start the battery; similarly, the use of unconfined "shake" shots in working places and other places in pitching veins may be permitted when necessary to bring down loose hanging coal that is too hazardous to take down

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