Teledyne 6200E - Sulfides Analyzer - Manual (Page 181)

Model 6200E Instruction Manual EPA Protocol Calibration
M6200E Rev: A1 181
8.1.2. Data Recording Device
Either a strip chart recorder, data acquisition system, digital data acquisition system should be
used to record the data from the Mode; M6200E RS-232 port or analog outputs. If analog readings
are being used, the response of that system should be checked against a NIST referenced voltage
source or meter. Data recording device should be capable of bi-polar operation so that negative
readings can be recorded.
8.1.3. Recommended Standards for Establishing Traceability
To assure data of desired quality, two considerations are essential: (1) the measurement process
must be in statistical control at the time of the measurement and (2) the systematic errors, when
combined with the random variation in the measurement process, must result in a suitably small
uncertainty.
Evidence of good quality data includes documentation of the quality control checks and the
independent audits of the measurement process by recording data on specific forms or on a quality
control chart and by using materials, instruments, and measurement procedures that can be traced
to appropriate standards of reference. To establish traceability, data must be obtained routinely by
repeat measurements of standard reference samples (primary, secondary, and/or working
standards). More specifically, working calibration standards must be traceable to standards of
higher accuracy, such as those listed in Table 7-1./.
Cylinders of working gas traceable to NIST-SRM's (called EPA Protocol Calibration Gas) are also
commercially available (from sources such as Scott Specialty Gases, etc.).
8.1.4. EPA Calibration Using Permeation Tubes
Teledyne Analytical Instruments does not recommend the use of permeation tubes as a source of
span gas for EPA protocol calibration operations.
8.1.5. Calibration Frequency
To ensure accurate measurements of the SO
2
concentrations, calibrate the analyzer at the time of
installation, and re-calibrate it:
• No later than three months after the most recent calibration or performance audit which
indicated analyzer calibration to be acceptable.
• An interruption of more than a few days in analyzer operation.
• Any repairs which might affect its calibration.
• Physical relocation of the analyzer.
• Any other indication (including excessive zero or span drift) of possible significant
inaccuracy of the analyzer.
Following any of the activities listed above, the zero and span should be checked to determine if a
calibration is necessary. If the analyzer zero and span drifts exceed locally established calibration