TSI Quest EVM-7 User Manual page 162

152 Appendix D
Particulate Measurements
Question
6. How do I know when to
clean the optical
engine/photometer?
7. How is the EVM-7 and
EVM-3 calibrated in the
factory?
8. Do I need to calibrate
before I run real-time
particulate
measurements?
9. When test collecting real-
time particulate
measurements for a period
of time, how do I verify the
calibration?
10. What if I need to calibrate
particulates in accordance
to NIOSH0600?
11. How many correction
factors can be stored on
the monitor and in DMS?
12. What if I want to enter in
the correction factor after
running/logging particulate
measurements?
Response/Solution
The following conditions may occur: (1) If calibrating the particulate (PM)
sensor and it will not zero, this indicates the optical engine will need cleaning.
(2) The instrument is exposed to oily or wet mists. (3) The readings are falling
lower and lower indicating the mirror is dirty. (Please see
on cleaning and maintenance.)
Each instrument is factory calibrated to the ISO 12103-A2 Fine (Arizona Road
Dust). A factory calibration is conducted with a "golden" instrument that is
calibrated using a certifiable gravimetric sample. TSI Incorporated
recommends a yearly factory calibration.
Yes, it is recommended to perform a zero calibration in each environment you
will be measuring particulates. To perform a zero calibration, ensure that the
zero filter/HEPA filter is attached, the impactor is well greased, and the turret is
set to PM. Then, using the keypad navigate to Calibrate>PM screen and
perform a zero calibration (see
calibration may be used when performing area-survey monitoring. However, if
you are testing in accordance to NIOSH0600 or if you want to measure the
actual mass concentration in a specific environment, you would run a
gravimetric calibration to determine a correction factor referenced to the ARD.
First, ensure you performed a zero calibration prior to your testing (with the
supplied Zero/HEPA filter). Run your real-time particulate measurements.
Then, perform a Calibration (PM) Verify via the Verify soft key/quick key (see
Chapter 4 for specific details.)
A gravimetric calibration is performed. The steps below outline a gravimetric
calibration (see Chapter 4
The EVM supports 8 different particulate matter (PM) configurations/profiles
with customized name settings and user correction factor settings. See
Chapter 3 for instrument profile set-up or
details.
You can adjust/change the correction factor in Detection Management
Solutions (DMS) after the session has been downloaded. The Dust Correction
Override feature is a type of scaling factor that will re-calculate the data
instantly in the chart or graph you are viewing. (NOTE: The Dust Correction
Override field is displayed in the General Data panel and is applied to the dust
measurements in the logged data chart/table when dust is the selected
parameter. To apply, select the dust override icon
Chapter 4 for specific details). NOTE: A zero
for specific details).
Chapter 6
Chapter 7 for details
for DMS set-up for more
and add a new value.)
EVM Series User Manual