Teledyne 9110EH - Nitrogen Oxides Analyzer - Manual (Page 148)

EPA Protocol Calibration Model 9110EH Instruction Manual
If more than one analyzer is to be calibrated at the same time, multiply F
T
by the number of
analyzers.
Calculate the NO concentration [NO]
OUT
needed to approximate 90% of the URL of the NO
2
analyzer to be calibrated, using Equation 8-2:
[NO]
OUT
= URL of analyzer (ppm) x 90/100 Eq 8-2
Calculate the NO flow (F
NO
) required to generate the NO concentration [NO]
OUT
, using
Equation 8-3:
] [NO
F x ] [NO
= F
STD
T OUT
NO Eq 8-3
Calculate the required flow through the ozone generator (F
O
), using Equation 8-4:
F -
min - ppm 2.75
V
X
F
X ] [NO
= F
NO
RC NO STD
o Eq 8-4
Verify that the residence time (t
R
) in the reaction cell is <2 min, using Equation 8-5:
min 2
F F
V
t
NO O
RC
R
≤
+
=
Eq 8-5
Verify that the dynamic parameter specification (P
R
) of the calibrator's reaction cell is
>2.75 ppm-min using Equation 8-6:
[ ]
75 . 2
F F
V
F F
F
NO P
NO O
RC
NO O
NO
STD R
≥
+
Ч
+
Ч =
Eq 8-6
NOTE
If t
r
is >2 minutes or if P
R
is <2.75 ppm min, changes in flow conditions
(F
T
, F
O
, F
NO
) or in the reaction cell volume (V
RC
), or both will
have to be made, and t
r
and P
R
will have to be recalculated.
After equations 8-5 and 8-6 are satisfied, calculate the diluent air flow (F
D
) using
Equation 8-7:
Eq 8-7 NO O T D
F F F F − − =
8.2.3. Example GPT Calculation
Following is an example calculation that can be used to determine whether an existing GPT
calibrator will meet the required conditions for a specific calibration. For this example, it is
134 M9110EH Rev 0