Mine Health and Safety Act, 1996 (Act No. 29 of 1996)NoticesGuideline for the Compilation of a Mandatory Code of Practice for the Prevention of Flammable Gas and Coal Dust Explosions in CollieriesAnnexuresAnnexure 2 : Guidance Note for the prevention of flammable gas and coaldust explosions in collieries3. Design Objectives |
3.1. | Only criteria based on empirical and proven scientific design applications should be considered. |
3.2. | Dust should be effectively controlled where generated, and not be permitted to escape from the heading uncontrolled and untreated so as to exceed acceptable levels. |
3.3. | Flammable gas should be diluted to acceptable levels by providing sufficient fresh air. |
DEFINITION:
Acceptable Levels
Dust Concentration (for less than 5% quartz content)
Personal sampling - a respirable eight-hour TWA concentration of less than 2 mg/m3 as per airborne pollutant sampling programme
Acceptable levels
Flammable gas concentration
A flammable gas concentration of less than 1,4%.
Last through road
The last through road in a coal mine will constitute the closest holing to the working faces between two companions, which carry a unidirectional flow of air from the intake to the return of the section.
Recirculation
When any amount of air which has been delivered by a particular ventilation system, ventilating a heading, re-enters the inlet of that system.
Return air
Air which has scrubbed the face of a heading.