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(continued)
(c) Warning shall be given immediately to all persons underground upon occurrence of fire or other emergency in or near the mine.




s 7076. (4-50) (11-53). Fire and Safety Diagram.
(a) A diagram of the mine shall be provided showing the location of:
(1) Principal levels
(2) Shafts

(3) Tunnels
(4) Manways
(5) Escape routes
(6) Fire doors
(7) Fire extinguisher
(8) Water and air lines available for fighting fire
(9) Telephones
(10) Refuge stations
(11) Ventilation doors
(12) Direction of air flow
(b) The diagram shall be brought up to date at least once every six months. It need not show boundary lines, outlines of ore bodies, or other details not essential for the safety of employees.
(c) Easily legible copies of the fire and safety diagram shall be kept posted on the surface near the mine entrance most frequently used by the men and at every working station in the mine.




s 7077. (11-53). Maps.
(a) The operator of every mine shall make and maintain, or cause to be made and maintained, a clear and accurate map, showing all the workings of such mine. All underground workings shall be surveyed and mapped before they are allowed to become inaccessible.
(b) Mine maps shall be brought up to date at least once every six months.
(c) The mine maps shall be available near the mine for inspection by the Division.




s 7080. Escapeways and Refuge Stations.
(a) (11-50) Every mine shall have two separate escapeways to the surface which are so positioned that damage to one shall not lessen the effectiveness of the other, or a method of refuge shall be provided when only one opening to the surface is possible.
(b) The escape exit shall be maintained within reasonable distance of the toping areas of the mine.
When the distance between the escape exit and any stope is computed by the following formula and the answer is one or more, the escape exit shall be extended in the direction of such stope until it is reasonable close.
T/1000 + S/300 = D
T = distance in feet of horizontal travel.
S = distance in feet of vertical and inclined travel.
D = symbol for total distance of travel.
For the purpose of this formula, an incline of less than 20 degrees from the horizontal will be considered as a horizontal passageway.
(c) (11-51a) Escape exits shall be maintained in good condition at all times so as to provide a ready means of escape for employees in case of emergency.
(d) (11-51b) All underground passageways and shaft stations shall be signed and marked by arrows pointing the way to and through the escape exit in a manner to expedite escape.
(e) The surface outlets from escape exits shall be not less than 100 feet from the exit most frequently used by the men.
The surface outlet of no two exits shall be covered by one building or by connected buildings.
(f) Where the use of a series or raises is contemplated for an emergency exit, the mine management is strongly advised to select the position of the raises so as to have them in line with one another, so that hoisting equipment can be installed if advisable at some future time.




s 7081. Refuge Stations.
(a) When the Division deems it necessary for the protection of employees, it may require that refuge stations be provided and maintained at such places within the mine as the Division may direct.
(b) Where feasible, the refuge station shall be located where it has two exits to the surface.
(c) (11-52d) The refuge station shall be provided with a water line, compressed air line, and telephone connection through each exit to the surface. The air lines and water lines shall be equipped with suitable valves which can be readily operated without the use of a tool.
(d) (11-52a c) Each refuge station shall be provided with fire doors so it can be isolated from other parts of the mine.
(e) (11-52b) Refuge chambers shall be large enough to accommodate readily the normal number of men in the particular area of the mine.
(f) (11-54) Telephone or other voice communication shall be provided between the surface and refuge chambers and such systems shall be independent of the mine power supply.




s 7083. Mine Rescue Stations.
(a) (4-67). Every mine at which more than fifty (50) men work underground at one time shall be provided with a mine rescue station located at or near the mine, or shall be a member of a cooperative mine rescue station located no greater distance from the member mine than can be covered by the most convenient means of transportation in 2 hours during any season of the year.
(b) At each mine in which the Division considers there is a serious hazard from mine fires or mine gases, the Division may require the installation of a mine rescue station, with apparatus and equipment as specified in Section 7084.
(c) (4-70) Smaller mines having 10 to 50 men underground at onetime shall join a cooperative mine rescue station or shall have one man for each 10 underground employees or fraction thereof trained annually in the use of breathing apparatus.
It is recommended that small mines, regardless of size, affiliate with a cooperative mine rescue station wherever practical. Where it is not practical, each mine should have some man in its organization who is trained and qualified in the use of breathing apparatus, to accompany mine rescue crews into the mine in case of emergency. This man should be familiar with the mine workings, mine ventilation, water lines, electrical circuits, and underground hoists.
(d) Each rescue station shall be in the immediate charge of a competent and responsible man. The man in charge need not be employed exclusively at the rescue station, but his employment shall be arranged so that he, or a competent and responsible substitute, shall be promptly available in case of need.
(e) Telephone, or other equally rapid means of communication, shall be maintained between the residence of the man in charge and the rescue station and every mine affiliated with the rescue station.




s 7084. (4-67) (4-69). Mine Rescue Equipment and Supplies.
(a) Except as provided in subsection (b) of this section, each mine rescue station shall be provided with the following respiratory equipment, supplies, and spare parts:
(1) Ten sets of permissible self-contained two-hour oxygen breathing apparatus.
(2) Sufficient spare parts to assemble one complete breathing apparatus in good working order.
(3) One high-pressure oxygen pump for recharging oxygen bottles.
(4) An emergency supply of oxygen and regenerator charges sufficient to keep 10 sets of breathing apparatus running for 10 hours.
(5) One signal line 1200 feet long and 1 reel for the signal line.
(6) Ten permissible electric cap lamps and charger.
(7) Necessary gas detection and ventilation instruments.
(b) On a showing that equal protection will be afforded to employees, the Division may permit mine rescue stations to be equipped with other types of permissible breathing apparatus and supplies than specified in subsection (a) of this section.
Permission to deviate from the provisions of subsection (a) must be in writing. Application to deviate must state the type of permissible breathing apparatus the applicant desires to use.
(c) Breathing apparatus shall be maintained in good working condition and ready for use. It shall be inspected at least once each month and any necessary repairs and adjustments shall be promptly made.
(d) The man in charge of the rescue station shall make a monthly report on a form prescribed by the Division. The report shall state the condition of the apparatus and equipment, and shall contain a record of the men trained during the month.
Copies of the monthly report shall be furnished to each member of a cooperative rescue station and to the Division of Industrial Safety.




s 7085. (4-67) (4-69). Mine Rescue Training and Procedure.
(a) Each mine required by Section 7083 (a) to have a mine rescue station or to be a member of a cooperative mine rescue station shall have at least 10 men trained annually in the use of permissible breathing apparatus as recommended by the U.S. Bureau of Mines.
A mine which is a member of a cooperative mine rescue station and which has fewer than 50 men underground at one time shall have trained annually in the use of breathing apparatus at least 1 man for each 10 underground employees or fraction thereof.
(b) At mines that are required to have men who are trained in the use of permissible breathing apparatus, at least 5 men shall practice with the apparatus each month, said practice to include work in an irrespirable atmosphere for at least 30 minutes. Five other men shall be trained the following month. Additional men should be trained. Where it is desirable to do so, 10 men may be trained every 2 months, instead of training 5 men each month.
All men designated to take this training shall be given a careful physical examination, and no man physically unfit for the work shall be allowed to take the training.
(c) Where practical, not more than 50 percent of the regular mine rescue crew shall be regularly employed underground at one time.




s 7086. (4-70). Use of Mine Rescue Equipment.
(a) As used in these Orders, "breathing apparatus" means a device which supplies the wearer with oxygen or air under low pressure for breathing purposes. By use of this device, the wearer carries his air with him and is independent of the atmosphere around him.
"Gas mask" is a device which is equipped with a canister containing chemicals. The wearer draws his air through the chemicals, which remove small amounts of poisonous gases by filtering or chemical action. As the gas mask does not provide oxygen for the wearer, it cannot be worn safely in an atmosphere containing a high concentration of gases or so low in oxygen that a flame safety lamp will not burn.
There are many types of gas mask canisters which are permissible for use as protection against certain gases or combinations of gases. However, there is only one type of canister that affords protection against carbon monoxide, the poisonous gas which is always present during mine fires and after mine explosions. This is the Type N canister, which is easily recognizable because of its red color.
No gas mask shall be used in a mine unless such gas mask is of a type designated as "permissible" by the U. S. Bureau of Mines and used only with a permissible Type N canister.
(b) No man shall be permitted to wear breathing apparatus in irrespirable mine air unless he is physically fit and has had the required training.
(c) Every rescue crew shall be composed of at least five men. A crew composed of six men is preferable.
(d) No breathing apparatus shall be used in irrespirable mine air unless such apparatus is of a type designated as "permissible" by the U.S. Bureau of Mines.
(e) Each apparatus shall be carefully inspected and tested before it is worn in irrespirable air.
The test shall be sufficient in scope to assure that the apparatus is air tight, and that its various parts are in good condition, functioning properly, and in safe condition to wear.
(f) Except in extreme emergency, only a full rescue crew of not less than five men shall be permitted to wear breathing apparatus in irrespirable air in any mine during a mine fire or for recovery work following a mine explosion.
(g) Except in extreme emergency, no rescue crew shall be permitted to wear breathing apparatus in irrespirable air unless a fully equipped reserve rescue crew is standing by, ready for service, in the most advanced fresh air station.
(h) Communication shall be maintained between the reserve rescue crew and the rescue crew in irrespirable air by means of a signal line.
(i) Care shall be used that the rescue crew does not proceed farther from its fresh air base than it can return safely to such base.
It is recommended that, except in extreme emergency, the rescue crew does not travel farther than 1,000 feet from its fresh air base over a level, unobstructed traveling way where visibility is good. Where necessary to climb ladders or other obstructions, or travel in dense smoke, the distance traveled should be shortened accordingly.
(j) Breathing apparatus should not be used to explore inactive mines or parts of mines because of the many dangers in addition to irrespirable air. Instead, it is recommended that a temporary ventilation system be installed and the exploration be made in fresh air.
If such exploration is undertaken, it shall be done only with a full rescue crew of not less than five men, with a second full rescue crew acting as a reserve in fresh air. Such crews shall be equipped with permissible breathing apparatus. Gas masks shall not be used for such exploration.
(k) Every rescue crew equipped with permissible gas masks shall be provided with a permissible flame safety lamp in good condition.
( l) No rescue crew using gas masks shall remain in an atmosphere where the permissible flame safety lamp will not burn.





s 7090. Environmental Controls.
(a) (5-1a) The exposure to airborne contaminants of a person working in a mine shall not exceed, on the basis of a time-weighted average, the threshold limit values adopted by the American Conference of Governmental Industrial Hygienists, as set forth and explained in the most recent edition of the Conference's publication entitled "Threshold Limit Values of Airborne Contaminants." Excursions above the listed threshold limit values shall not be of a greater magnitude than is characterized as permissible by the Conference. This paragraph (a) does not apply to airborne contaminants given a "C" designation by the Conference -for example, nitrogen dioxide.
(b) (5-1b) Employees shall be withdrawn from areas in which there is a concentration of an airborne contaminant given a "C" designation by the Conference which exceeds the threshold limit value (ceiling "C" limit) listed for that contaminant.
(c) General Industry Safety Orders for control of Dust, Fumes, Mists, Vapors, and Gases shall be minimum standards for mines.
(d) (5-2) Dust, gas, mist, and fume surveys shall be conducted as frequently as necessary to determine the adequacy of control measures.
(e) (5-5) Respirators shall not be substituted for environmental control measures. However, where environmental controls have not been developed or when necessary by nature of the work involved (for example, welding, sandblasting, lead burning), a person may work for reasonable periods of time in concentrations of airborne contaminants which exceed ceiling "C" limits or the limit of permissible excursions referred to in (a) and (b), if such person wears a respiratory protective device approved by the Bureau of Mines as protection against the particular hazards involved.
(f) (20-5) Carbon tetrachloride shall not be used unless under strict environmental controls.
(g) (20-9) Dusts suspected of being explosive shall be tested for explosibility. If tests prove positive, appropriate control measures shall be taken.




s 7091. (5-37)-(5-42). Underground Radiation Hazards.
The mandatory radiation standards of the Mine Safety and Health Administration for Metal and Non-Metallic Underground Mines, published July 31, 1969, February 25, 1970, and December 8, 1970, are adopted for control of underground radiation hazards.

Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.






s 7092. (5-3). Dust Control While Drilling.
When drilling holes with machines in rock or other dust-producing material, such dust shall be controlled as required by the General Industry Safety Orders.




s 7093. (5-3). Dust -Rock Drilling.
(a) For the purpose of these Orders "rock drilling" means drilling, cutting, chipping, channeling, or broaching rock by means of machinery.
"Wet drilling" means the continuous application of water through the central hole of hollow drill steel to the bottom of the drill hole.
(b) Rock drilling in underground mines is prohibited unless the dust is controlled by wet drilling or other means acceptable to the Division.
(c) Rock drilling machines purchased and used for wet drilling after the effective date of these Orders shall be equipped with a combination air throttle and water valve, so designed that the air cannot be turned on without turning on the water, and the water cannot be turned off without turning off the air.
(d) During wet drilling, the water flow shall be maintained continuously whenever the drill is in operation, including the period of collaring or starting the hole.
(e) Water for wet drilling shall be supplied to the drill in adequate quantities at a pressure of at least 40 pounds per square inch.
(f) Should the water supply or pressure for wet drilling become inadequate, such drilling shall be stopped immediately.




s 7094. (5-1). Dust -Mucking and Transferring Rock.
(a) The muck pile shall be wet down before mucking begins and shall be kept wet during the entire mucking operation to control the dust.
It is recommended that a continuous spray of water be maintained on muck piles where mucking machines are being operated.
(b) Water sprinklers shall be installed and used on all chutes from which dusty rock is taken, or other equally effective means acceptable to the Division shall be used to prevent harmful accumulations of dust in the atmosphere.
(c) Whenever a sprinkling device is installed at a chute, it shall be so placed that it can be operated by the workmen who operate the chute gates.
The spray shall be directed into the chute and away from the operator's position at the chute.
(d) To prevent spillage from loaded cars and trackless haulage vehicles from adding to the mine dust, the loaded car or vehicle shall not be moved away from the loading spot until the load has been trimmed and leveled so as to prevent spillage.
(e) Effective means shall be used to control the dust in manways, haulageways and other parts of the mine.
It is recommended that dust on haulageways be controlled with water, treating with calcium chloride, or other equally effective means.
In areas of water scarcity, it is recommended that water for dust control be treated with a wetting agent to increase its efficiency.




s 7095. (5-1). Dust, Smoke, and Gases After Primary Blasting.
(a) Except as provided in subsection (b) of this section, no primary blasting shall be done in a mine during the working shift, except where the ventilating currents are arranged so that dust, smoke, and gases from the blast go out of the mine without circulating through any active working place.
(b) Where it is necessary to do primary blasting during the working shift and the ventilating currents pass from the blast area through active mine workings, all employees shall be removed from such workings to the fresh air side of the blast area before the shots are fired.
(c) After a blast, employees shall not be required or permitted to return to their working places until the atmosphere of such places is reasonably free of smoke, dust, and gases from the blast.




s 7096. (5-1). Dust, Smoke, and Gases from Secondary Blasting.
(a) In order to protect employees from harmful dust, smoke, and gases from secondary blasting, such blasting shall not be done unnecessarily during the working shift.
(b) At permanent locations, such as bulldozing chambers, main grizzlies, draw points, and other control points where blasting is done throughout the working shift in the regular course of the work, employees shall be protected by one or more of the following, as necessary:
(1) A ventilation system that carries dust, smoke, and gases directly into the return air without circulation through any active working place.
(2) A system of water sprays that will blanket the area with a fine spray or mist during blasting, and long enough thereafter that the dust, smoke, and gases are allayed.
(3) Removal of employees from all areas of contamination until the atmosphere is reasonably free of dust, smoke, and gases.
(c) When blasting a chute that is equipped with water sprays, it is recommended that the sprays be turned on before the shot is fired.
(d) After a secondary blast has been fired, employees shall not be required or permitted to return to the blast area until the atmosphere is reasonably free of dust, smoke, and gases from the blast.
(e) If the amount of explosive used or the frequency of secondary blasting is such that serious contamination of active working places is apt to occur, employees in such places shall be removed to the fresh air side of the blast area.
Such employees shall not be required or permitted to return to their working places until the atmosphere is reasonably free of dust, smoke, or gases.





s 7098. Ventilation.
(a) The operator of every mine shall cause a good and sufficient current of fresh air to be circulated through every working place in the mine.
(b) The quantity of fresh air circulated through each working place shall be at least 200 cubic feet per minute for each person.
(c) Where workings are of such size or shape that air does not circulate satisfactorily in the vicinity of the workers, auxiliary ventilation shall be used.
(d) If the quantity of fresh air required by subsection (b) of this section is not sufficient to prevent harmful accumulations of dust, fumes, vapors, or gases, enough additional fresh air shall be provided to remove and prevent such accumulations.
(e) Men shall not be permitted, except in extreme emergencies, to work in a place where the oxygen content of the air is less than 19 1/2 percent by volume (dry basis).
(f) No man, unless he is wearing permissible, self-contained breathing apparatus, shall be permitted to work in a place where a flame safety lamp will not burn.
(g) (5-28) Unventilated areas shall be sealed or barricaded and posted against entry.




s 7099. Mechanical Ventilation.
(a) When the Division considers it necessary for the protection of employees, mechanically produced and positively controlled air currents shall be provided.
(b) For maximum accessibility and to isolate them from underground hazards, the main fan or fans shall be installed on the surface, unless permission in writing is secured from the Division for their underground installation.
Fans shall be so arranged that the mine entrances can be used for rescue or other purposes.
(c) For the protection of employees, the main fan or fans shall be installed so that the ventilating current can be quickly reversed in direction.
(d) Auxiliary fans underground shall be located so as to provide the best air available to the working place. Recirculation of air by auxiliary fans shall be avoided as far as practical.
(e) (5-22) All surface fans, casings, and air ducts shall be constructed wholly of noncombustible materials.
(f) Every fan house and every building within 50 feet of a fan house shall be constructed wholly of noncombustible material, or shall be made fire resistant by the use of gunite, cement plaster, metal sheathing, or by other equally effective means.
(g) Compressed air that does not contain smoke, harmful gases, or excessive oil may be used for ventilating purposes.
(h) Where underground fans are operated by electricity, all combustible material in the immediate vicinity shall be removed or made fire resistant.





s 7102. Dangerous Accumulation of Gases.
(a) When the air in any part of a mine is known to contain, or is suspected of containing, a dangerous accumulation of gas, it shall be tested before anyone is allowed to work therein.
(b) For the purpose of these Orders, a dangerous accumulation of gas is any gas, except flammable gas, in a concentration greater than listed in the General Industry Safety Orders as the maximum allowable concentration for such gas.
A dangerous accumulation of flammable gas is any mixture of flammable gas and air which exceeds 20 percent of its lower explosive limit.
(c) If an accumulation of gas is sufficient to endanger personsaway from its immediate vicinity, such persons shall be promptly taken out of the danger area until the gas is removed.
(d) When it is necessary to move an accumulation of gas, provision shall be made for the safety of employees in the area through which the gas is to be moved. Accumulations of gas shall be moved under the direction of a competent man.
(e) No one shall be permitted to work or be in a dangerous accumulation of gas unless he is wearing permissible respiratory equipment adequate for his protection.




s 7103. (21-1). Gassy Mine Classification.
(a) A mine shall be deemed gassy, and thereafter operated as a gassy mine, if:
(1) (21-1b) Flammable gas emanating from the orebody or the strata surrounding the orebody has been ignited in the mine; or
(2) (21-1c) A concentration of 0.25 percent or more, by air analysis, of flammable gas emanating only from the orebody or the strata surrounding the orebody has been detected not less than 12 inches from the back, face, or ribs in any open workings; or
(3) (21-1d) The mine is connected to a gassy mine; or
(4) (21-1a) The Division may designate any mine as gassy if history or past experience indicates that flammable gas in hazardous concentrations is likely to be encountered in such mine.





s 7104. Tests for Gases.
(a) Tests for flammable gases shall be made with a permissible methane detector or by chemical analysis.
Note: To be of most value in active mines, it is necessary that the percent of gas present be quickly and accurately determined. Because of the time required to collect and analyze air samples, and the relative insensitivity of the flame safety lamp, it is strongly recommended that a permissible methane detector be used for testing.
(b) Tests for any gas other than flammable gas shall be made by chemical analysis or by use of a testing device designed to detect the particular gas for which the test is being made, and to measure its concentration.
(c) When the air in any part of a mine is known to contain or is suspected of containing dangerous or explosive gas, it shall be tested by means acceptable to the Division of Industrial Safety before men are allowed to work therein. These tests shall be made by a man who has been certified by the Division to make them.
Every person requesting certification as a gas tester shall submit a completed application form to the Division. Upon submission of an application for certification as a gas tester, the Division shall collect the amount of $15.00 for examination fee which is non-refundable. Renewal fees are $5.00 annually.
Note: See Section 6967 (b) for Labor Code excerpts.

Note: Authority cited: Section 142.3, Labor Code.






s 7105. Mechanical and Electrical Equipment for Gassy Mines.
(a) Before installing mechanical equipment in a gassy mine, consideration shall be given to the use of power which will not be a source of ignition in a gaseous atmosphere.
Where practical, locomotives, material hoists, scraper hoists, auxiliary fans, and other equipment in the mine should be driven by compressed air.
(b) Before installing or using any electrical equipment in a gassy mine, the Division of Industrial Safety shall be advised of actual conditions. Such installations or operations shall be made according to specific orders to be issued by the Division for the particular location.





s 7106. (21-2)-(21-100). Gassy Mine Operation.
Gassy mines shall be operated in accordance with all mandatory U.S. Bureau of Mines Health and Safety Standards for Metal and Nonmetallic Underground Gassy Mines, published July 31, 1969, February 25, 1970, and December 8, 1970.
Note: The principal hazards of all shaft work are falls of persons; falling materials, including rock from operating skips and skip pockets; and skips in adjoining compartments which may strike workers or materials being handled.
Note: The hazards of falling persons and falling materials decrease as the incline of the shaft grows flatter, but a fall in a 20 degree shaft may cause painful or even serious injury.












NOTE: The principal hazards of all shaft work are falls of persons; falling
materials, including rock from operating skips and skip pockets; and skips in
adjoining compartments which may strike workers or materials being handled.

NOTE: The hazards of falling persons and falling materials decrease as the
incline of the shaft grows flatter, but a fall in a 20 degree shaft may cause
painful or even serious injury.




s 7110. Shaft Guarding.
(a) (19 -100) Every shaft shall be guarded at the top and at every shaft station.
(b) Guards for shafts shall conform to the following standards;
(1) The guards shall be substantially constructed, preferably, of solid materials, to keep objects from falling into the shaft. If solid materials are not used, openings in the guard shall not exceed one -half inch.

(2) The guards shall be securely fastened in place and, except when necessarily opened, the gates shall be kept securely closed.
(3) The guards and gates shall be at least 42 inches high and shall fit as closely to the floor as feasible.
(4) Any alternate means of guarding which will afford at least equal protection to employees and is acceptable to the division.
(c) The guards for all shafts shall be kept closed except when necessarily opened to:
(1) Load or unload the shaft conveyance.
(2) Make repairs to shaft.
(3) Perform other operations that cannot be performed with the guard in place.
At all times when a guard is removed, the employer shall provide other effective means to prevent men or materials from falling into the shaft.
(d) When a bucket or skip is used for hoisting, means shall be provided that will prevent material from falling into the shaft while being dumped.
(e) (19-105) All stations, levels, and skip pockets shall have a passageway around the working shaft where it is necessary for employees to cross through the shaft.
(f) Entering or crossing through a shaft, except to ascend or descend or for the purpose of inspecting or effecting repairs, is prohibited.
(g) In inclined shafts where the dip exceeds 45 degrees from the horizontal and men are hoisted in skips, the space between the hoisting compartments at each level station shall be closed by lining boards; and an iron bar or pipe of approximately 1-inch diameter shall be placed overhead above the divider in order to give men an easy and secure overhead handhold while walking on the divider.
(h) (19-101) Positive stopblocks or a detail switch shall be installed on all tracks leading to a shaft collar or lading.






s 7111. Shaft Work, Maintenance, and Repair -General.
(a) (19-107) Before maintenance or repair work is begun in a shaft, the person in charge of such work shall inform the hoistman of the nature of the work to be done.
(b) (19-108) Signs marked "Men Working in Shaft" shall be hung on the signal device in the hoist room and on or near the hoist brake during the time men are at work in a shaft compartment. The sign shall not be removed until the shaft men have notified the hoist operator that they are in the clear.
(c) When men are working in any compartment of a shaft, the shaft conveyance in any adjoining compartment shall not be operated except in an emergency or as directed by the shaft repair crew.
The hoisting conveyance of any adjoining compartment shall be spotted at the working place to prevent workers from falling into such compartment.
(d) All planks, timbers, bulkheads, and other materials used in repair work shall be removed to a safe place before regular hoisting operations are resumed.
They shall not be placed in a manway compartment in such manner as to impede safe and ready passage through the shaft.
(e) Wherever practical, maintenance work shall be carried on from the hoisting conveyance used in the shaft.
(f) If maintenance work is carried on from the top of the conveyance, a substantial platform or other safe footing securely fastened to the conveyance shall be provided for the workers.
In vertical shafts, an auxiliary bonnet shall be secured to the hoisting rope as closely above such platform as is practical for the work being done.
(g) (15-5) Unless protected by other means acceptable to the Division, approved safety belts shall be provided employees while working:
(1) In or over shafts or winzes inclined more than 45 degrees from the horizontal.
(2) In any portion of any shaft where, because of slippery footing or other local conditions, a serious fall may result.






s 7112. Shaft Work -Major Repair.
(a) To prevent injury to men and keep materials from falling down the shaft while extensive repair work is carried on, the following precautions shall be taken:
(1) A substantially constructed bulkhead shall be secured in place in the compartment where the repair operations are carried on, and as close below where the men are working as is practical.
(2) (19-77) When the shaft conveyance is lowered to the working place, it shall be stopped at least 15 feet above the working place and shall be held there until a further signal is given by the repair crew.






s 7113. (19-110). Protection Against Falling Materials.
(a) When a bucket or skip is used for hoisting while sinking a new shaft or deepening a shaft already in operation, workers in the shaft shall be protected against falling rocks and materials by one or both of the following means:
(1) Trap doors shall be installed at the shaft collar over openings in pentices and bulkheads, and under dumping points in the shaft for buckets and skips. Such trap doors shall be substantially constructed and so arranged that they can be readily and easily opened and closed.
It is recommended that trap doors at the collar be operated by compressed air and that the controls be located convenient to the hoistman.
(2) Some other equally effective means acceptable to the Division.






s 7114. (19-110). Deepening an Operating Shaft.
(a) No hoisting or other work shall be permitted in the upper part of the shaft while men are in the lower part, unless the men are protected by one or more of the following means:
(1) By leaving a rock pentice at the bottom of the shaft that is to be deepened. The depth of such pentice shall be not less than one and one-half times the least dimension of the shaft.

(2) By installing a substantial bulkhead at the bottom of the shaft to be deepened.
Such bulkhead shall consist of not less than 2 layers of heavy timbers placed with the layers at right angles to each other, and shall be covered with loose rock to a depth of not less than 15 feet .
(b) Any opening through the pentice or bulkhead shall be not larger than is necessary to accommodate the sinking operations, and shall not be located under the hoisting compartments of the shaft being deepened.






s 7115. Special Power-Driven Shaft Equipment.
Before special power-driven mechanical equipment is used in a shaft for sinking or enlarging operations, the mine operator shall notify the Division in writing of the provisions made for the safety of employees.
If considered necessary by the Division, additional safeguards shall be provided.
This section applies to shaft boring machines, shaft drill jumbos, shaft mucking devices, prime movers, and other mechanical appurtenances used in connection with the operation of such equipment.






s 7116. Hoisting While Sinking or Enlarging Shaft.
(a) In order to protect men working below the shaft conveyance, only first-class hoists shall be used to hoist or lower men or materials through any shaft or winze which is being deepened or enlarged.
This is not intended to prohibit the material hoist from auxiliary use, such as lifting equipment from the hoist conveyance, raising timbers into place, and similar work, when such use is confined to the immediate area of the working place. When a material hoist is used, no one shall be permitted under the suspended load.
(b) (19-77) When the shaft conveyance is lowered to the working place, it shall be stopped at least 15 feet above the working place and shall be held there until a further signal is given by the shaft workers.






s 7117. (11-55). Manway Compartment.
Every mine shaft, winze, or raise used for hoisting, and through which men are required or permitted to climb, shall be wide enough to accommodate a ladder, stairway, or ramp at a safe distance from the moving conveyance.






s 7118. (3-20). Shaft Safety Pillars.
No stopping shall be done within 20 feet of a shaft that is regularly used for hoisting men or is used as the main passageway for men entering or leaving the mine. In no case shall stopping be done so as to endanger the shaft.






s 7120. Hoisting Equipment for Materials.
Hoisting equipment for materials shall comply with the General Industry Safety Orders.




s 7121. Power-Driven Material Hoists.
(a) Material hoists shall not be used to hoist or lower men.
(b) Material hoists shall be installed in a safe location where falling materials from the load cannot endanger either the hoist or hoistman.
(c) Provision shall be made to prevent a pile-up of rope on the drum from overflowing the drum flange.
It is recommended that vertical roller be installed at each end of the drum to guide the incoming rope.
(d) Hands or feet shall not be used to guide the rope onto the drum. A mechanical guide may be used for this purpose, provided it is of a type that can be used safely.
(e) A substantial screen or other suitable guard shall be installed in front of each scraper hoist to protect the operator in event of a broken rope.




s 7122. Whims and Windlasses.
Whims and windlasses shall be provided with a reliable device to prevent accidental lowering of the bucket.




s 7123. Hoists.
(a) In addition to the regular operating controls, every hoist shall be provided with adequate means for disconnecting the power from the hoist.
(b) The means for disconnecting the power shall be located where it can be easily and safely manipulated by the hoist operator at his operating station.
(c) Power shall be disconnected from the hoist when:
(1) Movement of the hoist would endanger men working on or about the hoist or equipment moved by the hoist.
(2) The hoist is left unattended.
(d) (19-1) Hoists shall have rated capacities consistent with the loads handled and the recommended safety factors of the ropes used.
(e) (19-2) Hoists shall be anchored securely.
(f) (19-6) Automatic hoists shall be provided with devices that automatically apply the brakes in the event of power failure.




s 7124. Hoists at Shafts with Only One Exit.
At any mine which is entered by a shaft inclined at an angle more than 20 degrees from the horizontal, the hoist shall be a first-class hoist that complies with the standards set forth in Section 7126.




s 7125. Hoist for Hoisting and Lowering Men.
Only a first-class hoist shall be used for hoisting or lowering men.




s 7126. First-Class Hoists.
(a) (19-3) Belt, rope, or chains shall not be used to connect driving mechanisms to man hoists.
(b) The hoist shall be provide with ample power to hoist the fully loaded and unbalanced shaft conveyance from the lowest point in the shaft.
(c) (19-4) The hoist shall be equipped with 2 independent and separate braking systems, either of which shall be capable of holding 150 percent of the weight of the fully loaded and unbalanced shaft conveyance at any point in the shaft.
Such brakes shall be so arranged that the failure of one will not interfere with the proper operation of the other. One such braking system shall operate directly on the hoist drum.
(d) Brakes and other control devices shall be arranged and maintained so that they can be easily and safely manipulated by the hoistman at his operating station.
(e) No brake required by this section is acceptable if its operation depends on engaging a jaw clutch, multiple-tooth clutch, or similar device.
(f) (19-5) (19-65) The clutch and one brake on every hoist drum shall be so arranged that the brake must be applied before the drum can be unclutched, and the clutch must be engaged before the brake can be released.
(g) The clutch of every hoist drum shall be provided with means to prevent it being accidentally engaged or released.
(h) (19-9) Every hoist shall be provided with an indicator that will accurately show at any moment the position of the conveyance in the shaft.
It is recommended that the indicator be of a type that is operated by the hoist drum through a system of gears.
Belt-driven indicators are not acceptable because of the danger of the belt slipping or breaking.
(i) The hoist drums shall be provided with flanges that extend at least three diameters of the hoisting rope radially beyond the last layer of rope when all of the rope is coiled on the drum.
(j) Bolts and other fittings of the hoist shall be made secure by suitable locking devices.
(k) (19-120) The hoist shall be maintained in good operating condition. Parts that are defective, broken, cracked, or dangerously worn shall be repaired or replaced without delay.
( l) The hoist drum and head sheave shall be so aligned that the head sheave is at a right angle to the centerline of the hoist drum.
(m) The distance between the hoist drum and the nearest fixed sheave shall be not less than 15 feet for each foot of drum width.
(n) Each hoist drum and head sheave where men are hoisted or lowered shall have a minimum diameter according to the type of rope used, as given below:
6-strand 7-wire rope -42 times rope diameter
6-strand 19-wire rope -30 times rope diameter
6-strand 37-wire rope -18 times rope diameter
8-strand 19-wire rope -21 times rope diameter
(o) The hoistings rope shall be securely fastened to the hoist drum with at least four cable clips, or equivalent, and shall have at least three full wraps of cable on the drum when the hoisting conveyance is at its greatest depth.
(p) Only a first-class hoist shall be used for hoisting or lowering men.
(q) (19-7) Man hoists shall be provided with devices to prevent overtravel and overspeed.




s 7128. Design of Headframes.
(a) The headframe shall be so designed and constructed that it will resist a pull in the direction of the hoisting engine greater than the breaking strength of the hoisting rope employed.
(b) There shall be at least 15 feet of unobstructed hoistway clearance between the bottom of the head sheave and the top of the shaft conveyance or top connection for the hoisting rope, whichever is higher, when the bottom of such conveyance is at the top landing.
(c) (19-38) Every head sheave shall be provided with a platform for inspection and maintenance. Such platform shall be conveniently located, shall be of adequate size for men to work from safely, and shall be equipped with standard railings and toeboards.
(d) Safe access shall be provided to the head sheave platforms.
(e) The headframe, sheaves, bearings, and all accessories shall be maintained in safe and usable condition.




s 7129. (19-120). Shaft Conveyances -General.
(a) Every shaft conveyance shall be constructed of steel or other metal of equivalent strength acceptable to the Division.
(b) Safety dogs or catches shall be substantially constructed of steel. They shall be kept well oiled and in good working condition.
(c) At least once each work day, the weight on the hosting rope shall be relieved for activating and inspecting the safety dogs.
When deemed necessary by the Division of Industrial Safety, drop tests may be required in the presence of a representative of the Division.
(d) Should the safety dogs or catches fail to function properly while being tested, the shaft conveyance shall be removed from service until the safety dogs or catches have been put into satisfactory working condition.




s 7130. Shaft Guides.
(a) All shaft guides shall be Select Douglas Fir or equivalent, and shall be large enough in cross section to absorb the shock of stopping the fall of a shaft conveyance when gripped by the safety dogs or catches.
(b) Shaft guides shall be securely fastened in place with bolts or lag screws. Lag screws shall be screwed and not driven into place.




s 7131. Shaft Tracks.
(a) The tracks for the shaft conveyance in inclined shafts shall be made of steel or other metal of equal strength.
Exception: Wooden rails or skids may be used with a bucket when enlarging or deepening a shaft.
(b) Rails shall be well aligned and securely fastened in place.
(c) The connecting ends of rails shall be fastened together by use of splice bars or welds.
(d) Rail joints shall be supported adequately to prevent bending. It is recommended that rail joints be staggered for better stability.
(e) The track shall be maintained in good condition. Repairs, when needed, shall be made without unnecessary delay.




s 7132. Conveyances for Hoisting or Lowering Men in Vertical Shafts.
(a) (19-49) Except when using a bucket for sinking or repairing a shaft, every shaft conveyance in which employees are required or permitted to ride shall be provided with a man-deck for use of employees.
(b) (19-45) Every conveyance used for hoisting or lowering men in a vertical shaft shall be covered by a bonnet to protect persons riding therein.
(c) (19-45) The bonnet shall be constructed of mild steel plate at least three-sixteenths-inch thick, or equivalent, which shall slope toward each side and shall be so arranged that they may be readily pushed upward to afford egress to persons in the conveyance.
(d) (19-50c) The man-deck of every shaft conveyance shall be provided with side casings at least 5 feet high, the gates of which must be at least four and 4 1/2 feet high.
(e) Side casings and doors shall be substantially constructed of metal at least one-sixteenth-inch thick or of wire netting composed of wires at least one-sixteenth inch in diameter, with maximum openings not more than one-half inch.
(f) To prevent accidental opening while the shaft conveyance is in motion, doors shall be equipped with safety catches or other devices satisfactory to the Division.
The doors of the shaft conveyance shall be so arranged that they cannot be opened outward.
(g) Conveyances in vertical shafts shall have at least 1-inch clearance from all timbers and other objects in the shaft except guides for the conveyance.
(h) Every shaft conveyance in which employees are required or permitted to ride shall travel in guides and be equipped with safety dogs or catches of standard design to hold the fully loaded conveyance should the hoisting rope fail.
(i) (19-50a) Every hoisting bucket used in a shaft more than 50 feet deep shall be provided with a crosshead that travels upon guides and is equipped with safety dogs or catches of standard design. The height of the crosshead shall be not less than its width .
(j) (19-50b) Buckets used to hoist men during shaft sinking operation shall have devices to prevent accidental dumping.




s 7133. Conveyances for Hoisting or Lowering Men in Inclined Shafts.
Note: The chief hazards of hoisting and lowering men in inclined shafts are derailing the shaft conveyance, breaking the hoisting cable, falling rock or materials, and striking against fixed objects.
(a) Every shaft conveyance shall be provided with shaft guides or other satisfactory means to prevent derailment of the conveyance.
(b) Every shaft conveyance shall be equipped with a device to stop the conveyance should the hoisting rope fail.
(c) (19-45) Conveyances in shafts with a slope greater than 45 degrees from the horizontal shall be provided with bonnets constructed in accordance with the provisions of Section 7132(c).
(d) To prevent employees from being caught between the moving shaft conveyance and the shaft walls, chute lips, timbers, or other obstructions, one (1) or more of the following precautions shall be taken:
(1) At least 2 feet of overhead clearance shall be provided between men on the shaft conveyances in their riding position and the nearest shaft wall, chute lip, timber, or other obstruction.
At least 1 foot of clearance shall be provided between men on the shaft conveyance in their riding position and the nearest obstruction at the side of the shaft conveyance.
(2) The shaft conveyance shall be enclosed in such manner that men riding thereon cannot come in contact with obstructions along the shaft.

(3) The shaft conveyance shall be of such size and construction that men ride entirely inside the conveyance.
(4) Use of alternate means which will afford equivalent protection is acceptable to the Division.




s 7135. (19-21). Hoisting Ropes -Safety Factor and Inspections.
(a) Every hoisting rope used on a mechanically driven hoist shall be made of steel or alloy steel. The rope center may be fiber.
(b) Hoisting ropes shall be of adequate size to handle the intended load and shall have the following safety factors:

Minimum Minimum
safety factor safety factor when
Length of rope of new rope rope must be discarded
500 feet or less..... 8 6.4
500 to 1000 feet...... 7 5.8
1000 to 2000 feet..... 6 5.0
2000 feet and more.... 5 4.3


(c) The safety factor of a new rope shall be calculated by dividing the breaking strength of the rope as rated by the manufacturer by the sum of the maximum load to be hoisted, plus the total weight of the rope in the shaft when fully let out.
(d) (19-128) No rope shall be used for hoisting or lowering men:
(1) If there are six broken wires in one strand of a rope lay.
(2) If the wires on the crown are worn to 65 percent of their original diameter.

(3) If more than 3 wires have been reduced by wear more than 30 percent in cross section are broken in 1 strand of a rope lay.
(4) If marked corrosion appears.
(5) If minimum safety factor falls below that specified in subsection (b) of this section. (continued)