www.skcltd.com
770-300M Issue E
Page 13
Passive or Active Sampling
The Split2 monitor can be used in two operating modes, Passive or Active (with optional air
sample pump). The choice of which operating mode to use will depend on the dust fraction
of interest - Respirable or Inhalable fractions, and whether a filter sample is required for
subsequent gravimetric and/or chemical analysis.
A different configuration of the Split2 monitor sensor head is requried for the various options
as detailed below.
1) Passive Sampling
In Passive mode the sensor head is configured as shown below, with only the IOM front plate
fitted to the front of the sensor head and the sensor head mounted onto the bracket in the
orientation shown below. Secure the sensor head to the bracket with the two thumb screws
supplied.
In Passive mode the Split2 monitor is calibrated to respond to the respirable fraction only
and cannot be used to measure the inhalable fraction. Also, it is not possible to take a filter
sample for subsequent analysis in this operating mode.
2) Active (Pumped) Sampling
In Active mode the sensor head is configured as shown below and with the sensor head
mounted onto the bracket in the orientation shown. Refer also to the exploded diagram of
the sensor head on page 6 for component identification and assembly positions. Secure the
sensor head to the bracket with the two thumb screws supplied.