Release 08/2014 - Spectroquant
®
Multy
100687
Cell Test
Measuring range: 0.5 – 3000
1)
mg/l O
2
16-mm cell
1)
after corresponding dilution (details see package insert)
BOD
Biochemical Oxygen Demand
Fill approx. 10 ml of
distilled water into a
16-mm cell (do not add
any reagents!), close
with the screw cap.
(Blank cell)
Insert the blank cell
(nutrient-salt solution)
into the cell compart-
ment. Align the mark on
the cell with that on the
photometer.
Press Test .
Fill 2 oxygen reaction
bottles each with
pretreated sample
and 2 glass beads to
overflowing. Close
bubble-free with the
slanted ground-glass
stoppers.
Fill 2 oxygen reaction
bottles each with inocu-
lated nutrient-salt solu-
tion and 2 glass beads
to overflowing. Close
bubble-free with the
slanted ground-glass
stoppers.
Incubate one bottle
of pretreated sample
and one of inoculated
nutrient-salt solution
closed in a thermostatic
incubation cabinet at
20 + 1°C for 5 days.
Use one bottle of
pretreated sample
and one of inoculated
nutrient-salt solution
for the measurement
of the initial oxygen
concentration.
After incubation, use
one bottle of pretreated
sample and one of
inoculated nutrient-
salt solution for the
measurement of the final
oxygen concentration.
Measurement of inital
oxygen concentration
= Result 1
(measurement sample)
= Result 1
(blank)
Measurement of final
oxygen concentration
= Result 2
(measurement sample)
= Result 2
(blank)
Preparation and incubation:
Determination:
Select method 7 0 .
Add to each oxygen re-
action bottle 10 drops
of BOD-3K, reclose,
and mix.
Add to each oxygen
reaction bottle 5 drops of
BOD-1K and then 10
drops of BOD-2K, close
bubble-free, and mix for
approx. 10 seconds.
Transfer each solution
into a separate 16-mm
cell, close with the screw
caps.
Calculation:
BOD of measurement sample:
Result 1 – Result 2 (measurement sample) = A in mg/l
BOD of blank:
Result 1 – Result 2 (blank) = B in mg/l
BOD of original sample in mg/l = A • dilution factor – B
Insert the cell containing
the sample into the cell
compartment. Align the
mark on the cell with
that on the photometer.
Press Test .
Insert the blank cell into
the cell compartment.
Press Zero .
Quality assurance:
To check the measurement system (test reagents, meas-
urement device, and handling) Spectroquant BOD Stan-
dard (analogous to EN 1899), Cat.No. 100718, can be
used.
Check the pH of the
sample, specified range:
pH 6 – 8.
If required, add dilute
sodium hydroxide
solution or sulfuric acid
drop by drop to adjust
the pH.
Reaction time:
1 minute
