Program Policy Manual - VOLUME V - Mine Safety and Health ...

MSHA PROGRAM POLICY MANUAL VOLUME V
operator samples, are to be handled on an individual
basis. If dust concentrations are greater than 1.0
mg/m 3 , MSHA should require mine operators to add these
areas to the plan as designated area sampling locations.
5. Selection of Sampling Points Within DA:
The placement of the respirable dust sampling instrument
within a designated area is critical to obtaining a
representative measurement of respirable dust
concentrations at the location. Dust sampling
instruments should be positioned within designated areas
so that the measurement is indicative of the highest
dust exposure to personnel who are required to work or
travel in that area. The position of all dust sampling
instruments shall be described in the dust control plan
as required by 75.371(t). Guidelines for selection of
this position are:
a. Generally, within 10 to 20 feet downwind (with
direction of airflow) of the dust generating
source.
b. In belt entries, approximately 50 feet upwind
(opposite direction of airflow) from the center of
each intersection where air is directed into a
return airway.
c. At normal breathing level, but not less than 1 foot
from the roof or rib.
d. More than 2 feet from any obstruction and placed in
a manner where it will not be directly behind an
obstruction which would affect the airflow around a
sampling device.
e. Within 36 inches of the operator's control station
or normal work position, such as locomotive
operators, trackless haulage equipment operators,
etc.
6. Adding Designated Area Sampling Locations:
The district manager may require or accept designated
area sampling locations based on:
a. These guidelines.
October 2011 (Release V-43) 18