Thermo Fisher Scientific C101 Colorimeter - Manual (Page 38)

Measurement: Ozone
C105 Colorimeter
34
2.9 Ozone (0 – 4.1 ppm O
3
)
• DPD method
1
for Ozone - applicable to water, treated water,
wastewater and seawater.
Note: 1 Adapted from “Standard methods for the Examination of Water and
Wastewater.”
1. Switch the meter on by pressing the ON/OFF key. The display will
show [OZ] momentarily before displaying [STbY] indicating it is in
stand-by mode, waiting for either blanking or measurement.
2. Select a clean and dry vial, un-screw the cap and fill with sample
water to the line on the vial. Replace the cap, ensuring it is screwed
on finger tight to the vial.
3. Ensure the outside of the vial is clean, dry and absent of any marks
or finger-prints. Gently push the vial fully into the sample well of the
instrument, whilst aligning the ▼ mark on the vial with the ▲ mark on
the meter.
4. Press the ZERO key to initiate blanking of the meter. The display will
show [ZERo] while blanking is taking place.
Note: The meter will store and use the last blanking (or zero) value, even if it
is turned off, or if the batteries are removed.
Blanking
Sample
ZERO
ppm
5. Remove the vial from the meter and add into it the content of one
Chlorine, Total (DPD) Reagent Sachet.
6. Replace the cap, ensuring it is screwed on finger tight to the vial.
Invert the vial repeatedly for approximately 20 seconds, until the
powder has dissolved.
Note: A small amount of the powder may remain un-dissolved in the vial, but
this will not affect the measurement.