Teledyne 9110T Calibration Frequency, Calibration GAS and Zero AIR Sources, Data Recording Device

Model 9110T NOx Analyzer EPA Protocol Calibration

10.2.2. CALIBRATION GAS AND ZERO AIR SOURCES

10.2.2.1. Zero Air

Devices that condition ambient air by drying and removal of pollutants are available on the commercial market such as the Teledyne M701 zero air generator.

10.2.2.2. Span Gas

NO and NOx calibration gases supplied either directly from pressurized bottles of calibrated gas of different concentrations (see Table 3-8 or from a single source of high concentration gas then mixed to create various lower concentrations. In the latter case, we recommend using a gas dilution calibrator such as a Teledyne M700E.

In ALL cases, the gases and instrument(s) used must be calibrated and that calibration must be traceable to an EPA/NIST primary standard.

10.2.3. DATA RECORDING DEVICE

Either a strip chart recorder, data acquisition system, digital data acquisition system should be used to record the data from the 9110T 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. Strip chart recorder should be at least 6” (15 cm) wide.

10.2.4. RECORD KEEPING

Record keeping is a critical part of all quality assurance programs. Standard forms similar to those that appear in this manual should be developed for individual programs. Three things to consider in the development of record forms are:

∙Does the form serve a necessary function?

∙Is the documentation complete?

∙Will the forms be filed in such a manner that they can easily be retrieved when needed?

10.3.CALIBRATION FREQUENCY

A system of Level 1 and Level 2 zero/span checks is recommended (see Section 10.4). Level 1 zero and span checks should be conducted at least every two weeks. Level 2 checks should be conducted in between the Level 1 checks at a frequency determined by the user. Span concentrations for both levels should be between 70 and 90% of the reporting range.

To ensure accurate measurements of the NO, NOX, and NO2 concentrations, calibrate the analyzer at the time of installation, and recalibrate it:

∙No later than three months after the most recent calibration or performance audit that indicated the analyzer calibration to be acceptable.

∙An interruption of more than a few days in analyzer operation.

Teledyne Analytical Instruments 223