Pentair HAFFMANS c-DGM, Instruction Manual

Page: 18 / 79

HAFFMANS c-DGM/i-DGM
Page 18 of 78 c-DGM/i-DGM
4.5 *TPO measurement
When the c-DGM is used in combination with an ISD sampling device, the TPO value can be
determined in a sealed product packet. The traditional Uhlig's method, whereby the DO value is
multiplied by a Z factor (see Appendix I) is used to calculate the TPO value.
The use of Uhlig's method is based on an oxygen balance between the oxygen dissolved in the
liquid and the oxygen in the headspace volume. The closed product package must be shaken
for five minutes to achieve this balance. The package must settle for five minutes after the
package has been shaken, and then a measurement can be taken.