Wyoming Administrative Code › Agency 053 - Workforce Services, Department of › Sub-Agency 0004 - Mining Inspector › Chapter 4 - UNDERGROUND COAL MINES › Subpart D - Ventilation › Section 75.301 - Definitions

Current through July 13, 2024
In addition to the applicable definitions in 75.2, the
					 following definitions apply in this subpart.
Air course. An entry or a set of entries separated from
					 other entries by stoppings, overcasts, other ventilation control devices, or by
					 solid blocks of coal or rock so that any mixing of air currents between each is
					 limited to leakage.
Incombustible. Incapable of being burned.
Intake air. Air that has not yet ventilated the last
					 working place on any split of any working section, or any worked-out area,
					 whether pillared or nonpillared.
Intrinsically safe. Incapable of releasing enough
					 electrical or thermal energy under normal or abnormal conditions to cause
					 ignition of a flammable mixture of methane or natural gas and air of the most
					 easily ignitable composition.
Noncombustible Structure or Area. Describes a structure or
					 area that will continue to provide protection against flame spread for at least
					 1 hour when subjected to a fire test incorporating an ASTM E119-88
					 time/temperature heat input, or equivalent. The publication ASTM E119-88,
					 -Standard Test Methods for Fire Tests of Building Construction and Materials-is
					 incorporated by reference. . . [For inspection and approval information for
					 this publication, see Appendix at end of Subpart D.]
Noncombustible Material. Describes a material which when
					 used to construct a ventilation control results in a control that will continue
					 to serve its intended function for 1 hour when subjected to a fire test
					 incorporating an ASTM E119-88 time/temperature heat input, or equivalent. The
					 publication ASTM E119-88, -Standard Test Methods for Fire Tests of Building
					 Construction and Materials- is incorporated by reference. . . [For inspection
					 and approval information for this publication, see Appendix at the end of
					 Subpart D.]
Return air. Air that has ventilated the last working place
					 on any split of any working section or any worked-out area whether pillared or
					 nonpillared. If air mixes with air that has ventilated the last working place
					 on any split of any working section or any worked-out area, whether pillared or
					 nonpillared, it is considered return air. For the purposes of 75.507-1, air
					 that has been used to ventilate any working place in a coal producing section
					 or pillared area, or air that has been used to ventilate any working face if
					 such air is directed away from the immediate return is return air.
					 Notwithstanding the definition of intake air, for the purpose of ventilation of
					 structures, areas or installations that are required by this subpart D to be
					 ventilated to return air courses, and for ventilation of seals, other air
					 courses may be designated as return air courses by the operator only when the
					 air in these air courses will not be used to ventilate working places or other
					 locations, structures, installations or areas required to be ventilated with
					 intake air.
Worked-out area. An area where mining has been completed,
					 whether pillared or nonpillared, excluding developing entries, return air
					 courses, and intake air courses.