Co Co; Table 3-13: Nist-Srm's Available For Traceability Of So - Teledyne t100 Operation Manual

Getting Started
64
C (S ) G
ALIBRATION PAN
Calibration gas is specifically mixed to match the chemical composition of the type of
gas being measured at near full scale of the desired measurement range. In this case,
SO measurements made with the Teledyne API T100 UV Fluorescence SO
2
it is recommended that you use a span gas with a SO
measurement range for your application.
EXAMPLE: If the application is to measure between 0 ppm and 500 ppb, an appropriate
span gas concentration would be 450 ppb SO
Cylinders of calibrated SO
specifications (also referred to as SRM's or EPA protocol calibration gases) are
commercially available. Table 3-13 lists specific NIST-SRM reference numbers for
various concentrations of SO

Table 3-13: NIST-SRM's Available for Traceability of SO

NIST-SRM
1693a
1694a
1661a
1
2659a
2626a
2
2745
1
Used to calibrate optional O
2
Used to calibrate optional CO
S G M
PAN AS FOR ULTIPOINT
Some applications, such as EPA monitoring, require a multipoint calibration procedure
where span gases of different concentrations are needed. We recommend using a bottle
of calibrated SO gas of higher concentration in conjunction with a gas dilution
2
calibrator such as a Teledyne API Model T700 (Figure 3-17). This type of calibrator
precisely mixes a high concentration gas with zero air (both supplied externally) to
accurately produce span gas of the correct concentration. Linearity profiles can be
automated with this model and run unattended over night.
If a dynamic dilution system is used to dilute high concentration gas standards to low,
ambient concentrations, ensure that the SO
the dilution range of the calibrator.
Choose the SO gas concentration so that the dynamic dilution system operates in its
2
mid-range and not at the extremes of its dilution capabilities.
EXAMPLE:
•
A dilution calibrator with 10-10000 dilution ratio will not be able to accurately
dilute a 5000 ppm SO
at the very extreme dilution setting.
•
A 100 ppm SO gas in nitrogen is much more suitable to calibrate the T100 analyzer
2
(dilution ratio of 222, in the mid-range of the system's capabilities).
Teledyne API - T100 UV Fluorescence SO
AS
.
2
gas traceable to NIST-Standard Reference Material
2
.
2
Type
Sulfur dioxide in N
2
Sulfur dioxide in N
2
Sulfur dioxide in N
2
O in N
2 2
CO in N
2 2
CO in N
2 2
sensor.
2
sensor.
2
C
ALIBRATION
concentration of the reference gas matches
2
gas to a final concentration of 500 ppb, as this would operate
2
concentration equal to 80% of the
2
Calibration Gases
2
Nominal Concentration
50 ppm
100 pp
500 ppm
21% by weight
4% by weight
16% by weight
06807F DCN7335
Analyzer
2
Analyzer,
2