Page 226 - Advanced Mine Ventilation

206 Advanced Mine Ventilation

Table 12.7 Comparison of MCL Quartz Percentages to MSHA Quartz Percentages in
Respirable Dust for the Southern Appalachian Region

Reduced
3
Mine (Section) % Quartz (MCL) % Quartz (MSHA) Standard (mg/m )
Mine C
Section 1 4.1 7.1 1.4
Mine D
Section 1 5.2 14.3 0.7
Mine E
Section 1 2.3 7.1 1.4
Mine F
Section 1 5.7 9.1 1.1
Mine G
Section 1 0.0 12.5 0.8
Mine H
Section 1 4.5 9.1 1.1
Mine I
Section 1 3.5 9.1 1.1
Mine J
Section 1 0.0 8.3 1.2
Mine K
Section 1 0.0 8.3 1.2
Mine L
Section 1 0.0 8.3 1.2

of required samples varies between 5 and 86. Clearly the use of one sample for quartz
determination is unjustified. However, it would also be impractical to collect, analyze,
and average 86 samples.
A logical alternative would be to analyze the five samples collected for respirable
dust concentration determination. The samples are already being taken periodically
and sent to MSHA’s Pittsburgh laboratory to determine the concentration of respirable
dust. The same samples could then be analyzed for quartz and the mean exposure
determined. The samples would be taken every other month ensuring a prompt
follow-up.