4VAC25-40-5060. Gassy mines.
A mine shall be deemed gassy and thereafter operated as a gassy mine if:
1. Flammable gas emanating from the ore body or the strata surrounding the ore body has been ignited in the mine;
2. A concentration of 0.25% or more, by air analysis, of flammable gas emanating only from the ore body or the strata surrounding the ore body has been detected not less than 12 inches from the back, face, or ribs in any open workings; or
3. The mine is connected to a gassy mine.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.230, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5070. Effect of detection of flammable gases.
Flammable gases detected only while draining mines or flooded sections of mines, or during other mine reclamation operations, shall not be used to permanently classify a mine gassy. During such periods that any flammable gas is present in the mine, the gassy area of the mine shall be operated in accordance with appropriate standards in this article.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.231, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5080. Smoking materials prohibited.
Persons shall not smoke or carry smoking materials, matches, or lighters underground. The operator shall institute a reasonable program to ensure that persons entering the mine do not carry smoking materials, matches, or lighters.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.232, eff. July 19, 1989.
4VAC25-40-5090. Use of open flames.
Except when necessary for welding or cutting, open flames shall not be used in other than fresh air or in places where flammable gases are present or may enter the air current.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.233, eff. July 19, 1989.
4VAC25-40-5100. Supervision of use of open flames.
Welding or cutting with arc or flame underground in other than fresh air, or in places where flammable gases are present or may enter the air current, shall be under the direct supervision of a qualified person who shall test for flammable gases before and frequently during such operations.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.234, eff. July 19, 1989.
4VAC25-40-5110. Limit on percentage of gases.
Welding or cutting shall not be performed in atmospheres containing more than 1.0% of flammable gases.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.235, eff. July 19, 1989.
4VAC25-40-5120. Installation of main fans.
Main fans shall be:
1. Installed on the surface;
2. Powered electrically from a circuit independent of the mine power circuit. Internal combustion engines shall be used only for standby power or where electrical power is not available;
3. Installed in fireproof housing provided with fireproof air ducts;
4. Offset not less than 15 feet from the nearest side of the mine opening and equipped with ample means of pressure relief unless:
a. The opening is not in direct line with forces which would come out of the mine should an explosion occur; and
b. Another opening not less than 15 feet nor more than 100 feet from the fan opening is equipped with a weak wall stopping or explosion doors in direct line with the forces which would come out of the mine should an explosion occur;
5. Installed to permit prompt reversal of airflow; and
6. Attended constantly or provided with automatic devices to give alarm when the fans slow down to stop. Such devices shall be placed so they will be seen or heard by responsible persons.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.236, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5130. Operation of main fans.
Main fans shall be:
1. Operated continuously except when the mine is shut down for an extended period;
2. Provided with pressure-recording gauges; and
3. Inspected daily and records kept of such inspections and of fan maintenance.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.237, eff. July 19, 1989.
4VAC25-40-5140. Intakes and returns.
The main intake and return air currents in mines shall be in separate shafts, slopes, or drifts.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.238, eff. July 19, 1989.
4VAC25-40-5150. Single shaft intakes and returns.
When single shafts are used for intake and return, the curtain wall or partition shall be constructed of reinforced concrete or equivalent and provided with pressure relief devices.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.239, eff. July 19, 1989.
4VAC25-40-5160. Failure of fans.
When a main fan fails or stops and ventilation is not restored in a reasonable time, action shall be taken to cut off the power to the areas affected and to withdraw all persons from such areas.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.240, eff. July 19, 1989.
4VAC25-40-5170. Failure of ventilation.
When there has been a failure of mine ventilation other than a failure of a main fan as described in 4VAC25-40-5160, the operator shall:
1. Withdraw all persons from the unventilated active areas; and
2. De-energize the power in unvented active areas. The power shall not be restored or persons permitted to reenter the affected active areas until a certified foreman has determined that the flammable gas concentration in such active areas is less than 1.0%.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.241, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5180. Inspection after ventilation failure.
When ventilation is not restored in a reasonable time, all persons shall be removed from the affected areas; after ventilation has been restored, the areas affected shall be examined by a certified foreman for gas and other hazards and made safe before power is restored and before persons, other than the examiners and other authorized persons, return to the areas affected.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.242, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5190. Access of personnel after fan shutdown.
When the main fan or fans have been shut down with all persons out of the mine, no person, other than the certified foreman, shall go underground until the fans have been started and the mine examined for gas and other hazards and declared safe.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.243, eff. July 19, 1989.
4VAC25-40-5200. Operation of booster fans.
Booster fans shall be:
1. Operated by permissible drive units maintained in permissible condition;
2. Operated only in air containing less than 1.0% flammable gas; and
3. Kept in continuous operation when persons are in active areas of the mine affected by such fans.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.244, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5210. Equipping booster fans.
Booster fans shall be:
1. Provided with an automatic signal device to give warning or alarm should the fan system malfunction. The signal device shall be so located that it can be seen or heard by a responsible person at all times when persons are underground;
2. Equipped with a device that automatically de-energizes the power in unventilated active areas should the fan system malfunction; and
3. Equipped with two sets of controls capable of starting, stopping, and reversing the fans. One set of controls shall be located at the fans. A second set of controls shall be at another location remote from the fans.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.245, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5220. Installation and operation of auxiliary fans.
Auxiliary fans shall be:
1. Installed and operated in permissible condition; and
2. Operated only in air containing not more than 1.0% flammable gas.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.246, eff. July 19, 1989.
4VAC25-40-5230. Inspection of auxiliary fans.
Auxiliary fans shall be inspected by persons approved by the director at least twice each shift.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.247, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5240. Failure of auxiliary fans.
Persons shall be withdrawn from areas affected by auxiliary or booster fans when such fans slow down or stop.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.248, eff. July 19, 1989.
4VAC25-40-5250. Volume and velocity of air current.
The volume and velocity of the current of air coursed through all active areas shall be sufficient to dilute and carry away flammable gases, smoke and fumes.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.249, eff. July 19, 1989.
4VAC25-40-5260. Quantity of air standards.
The quantity of air coursed through the last open crosscut in pairs or sets of entries, or through other ventilation openings nearest the face, shall be at least 6,000 cubic feet a minute.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.250, eff. July 19, 1989.
4VAC25-40-5270. Measurement of air quantities.
At least once each week, a certified foreman shall measure the volume of air entering the main intakes and leaving the main returns, the volume of the intake and return of each split, and the volume through the last open crosscuts or other ventilation openings nearest the active faces. Records of such measurements shall be kept in a book on the surface.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.251, eff. July 19, 1989.
4VAC25-40-5280. Ventilation of battery-charging and transformer stations.
Permanently installed battery-charging and transformer stations shall be ventilated by separate splits of air conducted directly to return air courses.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.252, eff. July 19, 1989.
4VAC25-40-5290. Intake air for pumps and compressors.
Electrically-operated pumps, compressors, and portable substations shall be in intake air.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.253, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5300. Changes in ventilation.
Changes in ventilation that materially affect the main air current or any split thereof and may affect the safety of persons in the mine shall be made only when the mine is idle. Only those persons engaged in making such changes shall be permitted in the mine during the change. Power shall be removed from the areas affected by the change before work starts and not restored until the effect of the change has been ascertained and the affected areas determined to be safe by a certified foreman.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.254, eff. July 19, 1989.
4VAC25-40-5310. Adjustments in ventilation.
If flammable gas in excess of 1.0% by volume is detected in the air not less than 12 inches from the back, face and rib of an underground active area, or in air returning from an area or areas, adjustments shall be made in the ventilation immediately so that the concentration of flammable gas in such air is reduced to 1.0% or less.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.255, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5320. Detection of flammable gas.
If 1.5% or higher concentration of flammable gas is detected in air returning from an underground area or areas, the persons shall be withdrawn and the power cut off to the portion of the mine endangered by such flammable gas until the concentration of such gas is reduced to 1.0% or less.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.256, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5330. Use of air passing by opening of unsealed abandoned area to ventilate.
Air that has passed by an opening of any unsealed abandoned area and contains 0.25% or more of flammable gas shall not be used to ventilate working areas. Examinations of such air shall be conducted during the preshift examinations required by 4VAC25-40-5510.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.257, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5340. Use of air passing through abandoned panels to ventilate.
Air that has passed through an abandoned panel or area which is inaccessible or unsafe for inspection shall not be used to ventilate any working area in such mine. No air which has been used to ventilate any area from which the pillars have been removed shall be used to ventilate any working area in such mine, except that such air, if it does not contain 0.25% by volume or more of methane, may be used to ventilate enough advancing working areas immediately adjacent to the line of retreat to maintain an orderly sequence of pillar recovery on a set of entries.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.258, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5350. Abandoned areas to be sealed.
Abandoned areas shall be sealed or ventilated; areas that are not sealed shall be barricaded and posted against unauthorized entry.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.259, eff. July 19, 1989.
4VAC25-40-5360. Construction of seals.
Seals shall be of substantial construction. Exposed surfaces shall be made of fire-resistant material, or, if the commodity mined is combustible, seals shall be made of incombustible material.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.260, eff. July 19, 1989.
4VAC25-40-5370. Fitting of seals for atmosphere sampling and pressure measurement.
One or more seals of every sealed area shall be fitted with a pipe and a valve or cap to permit sampling of the atmosphere and measurement of the pressure behind such seals.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.261, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5380. Crosscut intervals.
Crosscuts shall be made at intervals not in excess of 100 feet between entries and between rooms.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.262, eff. July 19, 1989.
4VAC25-40-5390. Closing crosscuts.
Crosscuts shall be closed when necessary to provide adequate face ventilation.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.263, eff. July 19, 1989.
4VAC25-40-5400. Line brattices.
Line brattices or other suitable devices shall be installed from the last open crosscut to a point near the face to ensure positive air flow to the face of every active underground working area, unless the director or his authorized representative permits an exception to this requirement.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.264, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5410. Composition of brattices.
Brattice cloth shall be of flame-resistant material.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.265, eff. July 19, 1989.
4VAC25-40-5420. Damaged brattices.
Damaged brattices shall be repaired promptly.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.266, eff. July 19, 1989.
4VAC25-40-5430. Crosscuts at abandoned rooms.
Crosscuts shall be provided, where practicable, at or near the faces of entries and rooms before they are abandoned.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.267, eff. July 19, 1989.
4VAC25-40-5440. Where entries or rooms to be started.
Entries or rooms shall not be started off entries beyond the last open crosscuts, except that room necks and entries not to exceed 18 feet in depth may be turned off entries beyond the last open crosscuts if such room necks or entries are kept free of accumulations of flammable gas by use of line brattice or other adequate means.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.268, eff. July 19, 1989.
4VAC25-40-5450. Construction specifications for stoppings.
Stoppings in crosscuts between intake and return airways, other than room entries, shall be built of solid, substantial material; exposed surfaces shall be made of fire-resistant material, or if the material mined is combustible, stoppings shall be made of incombustible material.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.269, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5460. Airtight stoppings.
Stoppings shall be reasonably airtight.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.270, eff. July 19, 1989.
4VAC25-40-5470. Installation of air locks.
The main ventilation shall be so arranged by means of air locks, overcasts, or undercasts that the passage of trips or persons does not cause interruptions of air currents. Where air locks are impractical, single doors may be used if they are attended constantly while the areas of the mine affected by the doors are being worked, unless they are operated mechanically or are self-closing.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.271, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5480. Ventilation of air locks.
Air locks shall be ventilated sufficiently to prevent accumulations of flammable gas inside the locks.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.272, eff. July 19, 1989.
4VAC25-40-5490. Doors to be kept closed.
Doors shall be kept closed except when persons or equipment passing through the doorways.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.273, eff. July 19, 1989.
4VAC25-40-5500. Overcasts and undercasts.
Overcasts and undercasts shall be:
1. Constructed tightly of incombustible material;
2. Of sufficient strength to withstand possible falls from the back; and
3. Kept clear of obstructions.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.274, eff. July 19, 1989.
4VAC25-40-5510. Preshift examinations.
Preshift examinations shall be made of all working areas by certified foremen within three hours before any workers, other than the examiners, enter the mine.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.275, eff. July 19, 1989.
4VAC25-40-5520. Authorized personnel.
Only certified foremen and persons authorized to correct the dangerous conditions shall enter places or areas where danger signs are posted.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.276, eff. July 19, 1989.
4VAC25-40-5530. Removal of danger signs.
Danger signs shall not be removed until the dangerous conditions have been corrected.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.277, eff. July 19, 1989.
4VAC25-40-5540. Detection devices.
Each operator shall use permissible devices for detecting flammable gases, oxygen deficiency, carbon monoxide, and other air contaminants.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.278, eff. July 19, 1989.
4VAC25-40-5550. Frequency and method of examinations.
Examinations for dangerous conditions including tests for flammable gas with an acceptable device shall be made at least once each week, and at intervals of not more than seven days, by the certified foreman, except during weeks in which the mine is idle for the entire week.
The certified foreman shall:
1. Examine and make tests:
a. In the return of each split where it enters the main return;
b. On accessible pillar falls;
c. At seals;
d. In the main return;
e. In at least one entry of each intake and return airway in its entirety;
f. In idle workings; and
g. In abandoned workings, insofar as conditions permit;
2. Mark his initials and the date at the places examined;
3. Report dangerous conditions promptly to the operator or other designated person; and
4. Record the results of the examination with ink or indelible pencil in a book kept for that purpose at a designated place on the surface of the mine.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.279, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5560. Examination reports.
The certified foreman or other designated mine official shall read and countersign promptly the reports of daily and weekly examinations by competent persons and shall take prompt action to have dangerous conditions corrected.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.280, eff. July 19, 1989.
4VAC25-40-5570. Ventilation of gassy mines.
All gassy mines shall be ventilated mechanically.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.281, eff. July 19, 1989.
4VAC25-40-5580. Airflow to be maintained.
Airflow shall be maintained in all intake and return air courses of a mine. When multiple main fans are used, such ventilation systems shall not develop areas without perceptible air movement.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.282, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5590. Fan installation doors.
In mines ventilated by a combination of multiple blowing or multiple exhausting fans, each main fan installation shall be equipped with noncombustible doors designed and positioned so that, in the event of failure of a main fan, these doors will automatically close to prevent air reversal through the fan. The doors shall be located so that they are not in direct line with forces which would come out of the mine, should an explosion occur.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.283, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5600. Diesel-powered equipment.
Diesel-powered equipment shall not be taken into or operated in places where flammable gas exceeds 1.0% of any point not less than 12 inches from the back, face and rib.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.284, eff. July 19, 1989.
4VAC25-40-5610. Trolley wires.
Trolley wires and trolley feeder wires shall be on intake air and shall not exceed beyond the last open crosscut or other ventilation opening. Such wires shall be kept at least 150 feet from pillar workings.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.285, eff. July 19, 1989.
4VAC25-40-5620. Permissible equipment required.
Only permissible equipment maintained in permissible condition shall be used beyond the last open crosscut or in places where dangerous quantities of flammable gases are present or may enter the air current.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.286, eff. July 19, 1989.
4VAC25-40-5630. Permissible distribution boxes required.
Only permissible distribution boxes shall be used in working areas and other areas where dangerous quantities of flammable gas may be present or may enter the air current.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.287, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5640. Electric equipment.
No electric equipment shall be taken into or operated in places where flammable gas can be detected in the amount of 1.0% or more at any point not less than 12 inches from the back, face and rib.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.288, eff. July 19, 1989.
4VAC25-40-5650. Permissible electric lamps.
Only permissible electric lamps shall be used for portable illumination underground.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.289, eff. July 19, 1989.
4VAC25-40-5660. Permissible or approved explosives.
Only permissible or other types of explosives approved by the director shall be used in gassy mines.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.290, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5670. Written list of conditions.
The division, in granting approval referred to in 4VAC25-40-5660, shall provide the operator with a written list of conditions for using the specific explosives covered by the approval and adapted to the mining operation.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.291, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5680. (Repealed.)
Historical Notes
Derived from VR480-05-1.2 §§ 15.292, 15.293, eff. July 19, 1989; repealed, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5700. Examinations for gas.
Examinations for gas shall be made immediately before and after each shot or round.
Statutory Authority
§§ 45.1-161.3 and 45.1-161.294 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.294, eff. July 19, 1989.
4VAC25-40-5710. Limitations on firing shots.
Shots or rounds shall not be fired in places where flammable gas can be detected with a permissible flame safety lamp, or where 1.0% or more of flammable gas can be detected by any other MSHA approved device or method, at a point not less than 12 inches from the back, face and rib. See Article 4 (4VAC25-40-3325 et seq.) of this part for blasting requirements.
Statutory Authority
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Historical Notes
Derived from VR480-05-1.2 § 15.295, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5720. (Repealed.)
Historical Notes
Derived from VR480-05-1.2 § 15.296, eff. July 19, 1989; repealed, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.
4VAC25-40-5730. (Repealed.)
Historical Notes
Derived from VR480-05-1.2 §§ 16.1, 16.2, eff. July 19, 1989; repealed, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.