Home : BOD Manager Criteria Setup
Q10883 - INFO: BOD Manager Criteria Setup

BOD testing is complicated due to the number of criteria that tests must meet for acceptance.  The BOD Manager checks tests for compliance with these criteria as they are defined in the Criteria Setup.  Default values for criteria are based on values recommended in Standard Methods for the Examination of Water and Wastewater, 16th Edition.  Values may be edited to meet requirements of state or other regulating agencies.

BUTTONS:

click this button to set the BOD Manager default form size to the current form size (i.e., set the form size to a desired size and then click this button to save the setting

accepts all settings and saves them to the database

cancels any settings changed and exits Criteria Setup

sets all settings to their default settings

outputs the settings to a specified printer

 

Field Descriptions

Volume of the BOD bottles (ml):  The volume of the test bottles used for incubation.  This is not a checked criterion, but is required for use in BOD calculations.  The default value is 300 ml.

Maximum Dilution Blank Oxygen Depletion (mg/l):  Maximum acceptable value for Initial D.O. minus Final D.O. in the dilution-blank test.  This criterion is checked only for tests with a sample name of DilBlank.  The default value is 0.2 mg/l.

Maximum Initial Dissolved Oxygen (mg/l):  The maximum acceptable value for the Initial D.O.  This is checked for all tests.  The default value is 9.0 mg/l.

Minimum Final Dissolved Oxygen (mg/l): The minimum acceptable value for the Final D.O.  This is checked for all tests.  The default value is 1.0 mg/l.

Minimum (Initial D.O. - Final D.O.) (mg/l): The minimum acceptable value for oxygen depletion.  This is checked for all tests except the dilution-blank tests.  The default value is 2.0 mg/l.

Minimum Oxygen Depletion % for Seed Tests (mg/l):  The minimum percent that bottle dissolved oxygen should decrease.  Checked for tests with a sample name of Seed.  This criterion is not checked if default values are used.  If used, a typical value is 40.

Maximum Oxygen Depletion % for Seed Tests (mg/l):  The maximum percent that bottle dissolved oxygen should decrease.  Checked for tests with a sample name of Seed.  This criterion is not checked if default values are used.  If used, a typical value is 70.

Minimum Seed Correction Factor (mg/l):  The minimum acceptable value of the seed correction factor.  The value checked is not the seed correction per ml.  It is the actual seed correction used in BOD calculations derived by multiplying the seed correction per milliliter by  the amount of seed used in the test.  This is checked for any test using seed.  The default value is 0.6 mg/l.

Maximum Seed Correction Factor (mg/l):  The maximum value of the seed correction factor.  This is checked for any test using seed.  The default value is 1.0 mg/l.

Minimum Standard Test BOD (mg/l):  The minimum acceptable value of BOD for tests with the sample name Standard.  The default value is 163 mg/l (or, 200 minus 37).

Maximum Standard Test BOD:  The maximum acceptable value of BOD for tests with the sample name Standard.  The default value is 237 mg/l (or, 200 plus 37).

Check Coefficient of Variation:  Calculates a Coefficient of Variation (CV) for all dilutions in a sample (up to three dilutions) and checks that value against the CV Limit.  If the CV Limit is exceeded, the lowest concentration dilution is marked and the CV is calculated for the remaining dilutions and the CV is checked again.  This process is repeated until the calculated CV is within limit or only one bottle remains. 

CV = Standard Deviation / Avg BOD 

Coefficient of Variation Limit:  The maximum acceptable CV for a bottle.   Default is 0.35.  NOTE:  BOD Manager does NOT multiply the CV times 100, therefore enter your CV Limit as a decimal.

If all Final DO's in Sample are <1 use 1 and report as greater than: Sets what to calculate if all of the dilutions for a sample have a Final DO that is <1 mg/L.

OFF Do not calculate a Final BOD

ON Select the smallest sample volume and assume a Final DO of 1, calculate the BOD and report the Final BOD as > the Calculated BOD.

On  (Remove 1 from Initial) Select the smallest sample value and assume a Final DO of 1, subtract 1 from the initial DO, calculate the BOD and report the Final BOD as > the Calculated BOD.


If all Depletions in Sample are <2 use 2 and report as less than: 
Sets what to calculate if all depletions for a sample do not deplete at least 2 mg/L.

OFF Do not calculate a Final BOD.

ON Select the largest sample concentration and assume a depletion of 2, calculate the BOD and report the Final BOD as < the Calculated BOD.  Note: Seeding is ignored in the calculation when the depletion of 2 is used.  See Example 3 in BOD Manager Example Calculations.


BOD form width (twips):
Sets the width that the BOD Manager will be displayed to in twips.  If you have resized the BOD Manager form the to size you want, simply click Current.

BOD form height (twips):  Sets the height that the BOD Manager will be displayed to in twips.  If you have resized the BOD Manager form the to size you want, simply click Current.

Report Header as CBOD: Sets BOD Worksheet report title to "CBOD Calculations Report for date" vs "BOD Calculations Report for date".  Tech Note: Saved to OPSROOT.GENERALSETTINGS BOD_MANAGER_REPORT_CBOD field.

Show Initial Temperature:  Sets whether to display/track the Initial Temperture for each bottle in the BOD Manger.

Show Initial pH: Sets whether to display/track the Initial pH for each bottle in the BOD Manager.

Show Final Temperature:  Sets whether to display/track the Final Temperture for each bottle in the BOD Manager.

Related Articles
No Related Articles Available.

Article Attachments
No Attachments Available.

Related External Links
No Related Links Available.
Help us improve this article...
What did you think of this article?

poor 
1
2
3
4
5
6
7
8
9
10

 excellent
Tell us why you rated the content this way. (optional)
 
Approved Comments...
No user comments available for this article.
Created on 4/5/2008 4:11 PM.
Last Modified on 4/25/2022 7:43 AM.
Last Modified by Scott Dorner.
Article has been viewed 8592 times.
Rated 5 out of 10 based on 9 votes.
Print Article
Email Article