User Guide
175
8. CALIBRATION PROCEDURES
This chapter describes the calibration procedures for the M100E. All of the methods described in this section can
be initiated and controlled through the COM ports.
NOTE
If you are using the M100E for US-EPA controlled monitoring, refer to Chapter 9 for information on the
EPA calibration protocol.
8.1. CALIBRATION PREPARATIONS
The calibration procedures in this section assume that the analog range and units of measure, range mode, and
reporting range have already been selected for the analyzer. If this has not been done, please do so before
continuing (refer to Section 6.7 for instructions).
NOTE
:
It is recommended that the LAMP CAL routine (refer to Section 6.9.7) be performed prior to all calibration
operation. This will allow the instrument to account for minor changes due to aging of the UV lamp.
8.1.1. REQUIRED EQUIPMENT, SUPPLIES, AND EXPENDABLES
Calibration of the M100E analyzer requires a certain amount of equipment and supplies. These include, but are
not limited to, the following:
Zero-air source
Sulfur dioxide span gas source
Gas lines - all gas line materials should be Teflon-type or glass.
A recording device such as a strip-chart recorder and/or data logger (optional).
8.1.2. ZERO AIR
Zero air is similar in chemical composition to the Earth’s atmosphere but scrubbed of all components that might
affect the analyzer’s readings. For SO
2
measuring devices, zero air should be similar in composition to the
sample gas but devoid of SO
2
and large amounts of hydrocarbons, nitrogen oxide (NO) and with a water vapor
dew point ≤ -15°
C.
Devices such as the API Model 701 zero air generator that condition ambient air by drying and removal of
pollutants are available. We recommend this type of device for generating zero air.
8.1.3. CALIBRATION GAS STANDARDS & TRACEABILITY
Span gas is specifically mixed to match the chemical composition of the gas being measured at about 80% of
the desired full measurement range. For example, if the measurement range is 500 ppb, the span gas should
have an SO
2
concentration of about 450 ppb.
Span gases should be certified to a specific accuracy to ensure accurate calibration of the analyzer. Typical gas
accuracy for SO
2
gases is 1 or 2 %. SO
2
standards should be mixed in nitrogen.
04515F DCN6048