YSI BODAnalyst - Manual (Page 25)

Batches Section 5
YSI Incorporated BOD Analyst for Windows Software 21
Notes: Used for any miscellaneous notes for the entire batch.
Bottle Notes: This field allows entry of bottle specific notes. As the cursor is moved around the
bench sheet the notes for the current bottle will be displayed. This allows users to enter the pH of
the bottle if it is required by the state.
5.13 COLUMN DESCRIPTIONS
Sample Name: Identifies the sample.
Bot tle #: The number of the BOD bottle used for incubation.
Pre Dil: The pre-dilution ratio for the bottle. Very strong samples sometimes require dilutions
that would be difficult to make in one step. In these cases, a sizeable quantity of sample is first
diluted to a ratio that will make the final dilutions practical. Sometimes a pre-dilution is called a
serial dilution. In the BOD Analyst software, we call this ratio the pre-dilution. For example, if
you add 10 ml of your dairy farm sample to a 1000 ml volumetric flask and then fill the flask with
dilution water, enter 100 (1000/10) for the Pre Dil ratio. The Pre Dil ratio defaults to 1. This
column appears only if the “Do you predilute your bottles?” field in General Setup is checked.
Samp Volume (ml or %): The sample volume in milliliters or % in the BOD bottle. Use the
Dilution Unit field in General Setup to choose whether to enter this number in ml or %.
Seed Volume (ml): The seed volume in milliliters introduced into the BOD bottle. If the field is
left blank, Seed Vol defaults to zero.
Init DO (mg/l): The amount of dissolved oxygen at the beginning of the incubation period
measured in milligrams per liter.
Final DO (mg/l): The amount of dissolved oxygen at the end of the incubation period measured
in milligrams per liter.
O
2
Depl (mg/l): The amount of dissolved oxygen as mg/l consumed during the incubation period.
If blank compensation is turned on, the depletion calculation will remove the depletion due to the
Blank Water. This field is automatically calculated:
= (NormFactor * (InitDO – FinalDO)) - (BlankComp per ml * Blank Water in Sample)
Seed Factor (mg/l): Used to correct the BOD test for oxygen depletion resulting from the
presence of seed. Seed correction per ml is derived from seed control tests, then multiplied by the
amount of seed used in the test, as shown below. If there is no seed used in the test the seed
factor is zero. The seed factor will also be shown as zero if all seed tests are marked as
unacceptable. This can produce invalid results for tests that use seed.
Seed Factor = Seed Correction per ml * Seed Vol
BOD (mg/l): The calculated BOD for the bottle.
Final BOD (mg/l): Calculated by averaging the BODs of all dilutions for a sample that have not
been marked as unacceptable.