OdaLog
®
Gas Logger User Manual
P/N: 10-1000
Revision: F, Issued: October 2019
Page: 23
9 CALIBRATING THE OdaLog
®
9.1 Preparation for Calibration
Calibration of an OdaLog
®
must take place in a known clean, fresh air environment at an ambient temperature
of between 20
o
C and 25
o
C.
A clean, fresh air environment is one that is free of flammable gases and interfering or contaminating substances
(hereafter known as ‘Clean Air’).
Cigarette smoking, the use of butane lighters or solvents nearby, industrial fumes, or vehicle exhaust can cause
an incorrect, and hence potentially inaccurate, calibration.
Ensure the OdaLog
®
has sufficient battery life and that filters are uncontaminated and undamaged.
9.2 Adsorption of Calibration Mixture
Care should be taken when selecting the regulator material, tubing type and length used for calibration. For
certain calibration mixtures, instead of the gas passing freely through the gas regulator & tubing, molecules of
test gas can attach themselves to the regulator & tubing walls, thus reducing the concentration of calibration
mixture that reaches the instrument sensor. This effect in known as adsorption and is more noticeable with
certain calibration mixtures than others, particularly hydrogen sulphide.
Advice in relation to suitability of regulators & tubing should be sought from the calibration mixture supplier.
9.3 Tools and Test Equipment
The following equipment is required to perform a calibration on an OdaLog
®
instrument:
Calibration mixture:
To suit sensor type (refer: Table 5). Calibration mixture should be equivalent to 25-
50 percent of full-scale concentration, ideally near mid-scale. However, lower concentrations are
recommended for toxic gases in the interest of safety. Calibration mixture should be certified or analysed
to be accurate to at least ±5 percent of the actual labelled concentration.
Gas bottle regulator:
To suit gas type & flow rate (refer: Table 5)
Calibration fitting/adaptor:
Complete with tubing of suitable type, size & length. [Part Number 11-0001]
Magnetic ended Allen Tool:
[Part Number: 11-0000]
Calibration procedure document:
Section 9 of this manual.
CAUTION
OdaLog Instruments should be calibrated by authorised, competent personnel
using the correct equipment. If unsure, or the correct equipment is not available,
then return the instrument to Thermo Fisher Scientific or an authorised distributor
/ technical workshop for calibration.
CAUTION
Ensure calibration is undertaken in a well ventilated area or fume cupboard. Seek
advice from calibration mixture supplier in relation to handling calibration gases.