4
Zero/HEPA Filter Example
Used for particulate zero cal.
Tubing and Vent Opening
Insert tubing into the
impactor of the labeled “2.5”
vent opening
Turret
Turn the turret so “PM”
appears on the display of
the EVM.
Particulate Zero Calibration
Prior to calibrating, ensure the impactors are well-greased with an applied thin-film of silicone grease.
(Please see “Impactor Care” on page 10 of EVM series user manual.)
1. Attach the
Zero/HEPA
filter and tubing
into the turret. Rotate the turret to PM.
2. Select
Calibration
from the
Start
screen
and select
PM
(using up/down arrows).
3. Press
Cal
softkey and then press
Start
softkey. Once level is stabilized,
press
Set
softkey.
4. Once level has been set, you can press
Save
or
Cancel
. (Please refer to
Chapter 4 of EVM series manual for
more information.)
NOTE: Once saved, the instrument will apply the zero calibration to all profiles. The zero calibration is
stored in the History screen and a calibration. Verify can be performed (to ensure no drifting).
Particulate Advanced Calibration (Gravimetric)
Gravimetric Calibration Overview
(1)Reset the gravimetric and volume accumulators; (2) Insert a new (sealed) gravimetric cassette;
(3) Measure in the specific location for approximately four to eight hours; (4) Record the value displayed
in the gravimetric accumulator field displayed in the particulate screen. (This value is used in conjunction
with the weight of the measured dust in the cassette.); (5) Remove the gravimetric cassette and weigh
the filtered contents. (Typically, send to a lab for results.); (6) To determine the correction factor, calculate
the ratio between the particulate mass value and the weight from the gravimetric filter lab analysis.
(Ratio = true weight/EVM gravimetric displayed value). (7) Enter user correction value (Setup\Particulate
screen. Select profile field and then press Edit softkey. Add Factor using up/down arrows. Press On/OFF/
Esc key twice to return to start screen.)
Logging Particulates
1. Before logging particulates, ensure the impactors are clean and well-greased.
2. From the start screen or any measurement screen, press key .
3. Press key to end the logged session. (See “Viewing logged results” to access past sessions.)
