Thermo Scientific 410iQ, Instruction Manual

Page: 161 / 306

Thermo Scientific 410iQ Instruction Manual 4-1
Chapter 4
Calibration
This chapter describes the procedures for performing a standard zero/span
calibration and a multipoint calibration of the 410iQ. The information
described here is more than adequate to perform the calibration. However,
if greater detail is needed, please refer to the
Quality Assurance Handbook for
Air Pollution Measurement Systems 1 .
The following sections discuss the required apparatus and procedure for
calibrating the instrument.
The following equipment is required to calibrate the instrument:
A cylinder of CO
2
in air containing an appropriate concentration of CO
2
suitable for the selected operating range of the analyzer under calibration is
necessary. The assay of the cylinder must be traceable either to a National
Institute of Standards and Technology (NIST) CO
2
in Air Standard
Reference Material (SRM) or an NIST/EPA approved gas manufacturer's
Certified Reference Material (CRM).
A recommended protocol for certifying CO
2
gas cylinders against a CO
2
,
SRM or CRM is given in the Quality Assurance Handbook 1 . The CO
2
gas
cylinder should be recertified on a regular basis determined by the local
quality control program.
Calibration requires zero air that is free of contaminants which will cause a
detectable response on the CO
2
analyzer. The zero air should contain <0.5
ppm CO
2
.
Depending on the grade, zero air as supplied in cylinders from commercial
suppliers typically contains CO
2
concentrations in the 0.1 to 400 ppm
range. So cylinder zero air should be scrubbed of the residual CO
2
prior to
its use in the instrument as a dilution gas or a zero standard.
Equipment Required
CO
2
Concentration
Standard
Zero Air Generator