Hach BODTrak II, User Manual

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• B = corrected BOD of the seed blank
• SA = volume of seed in seeded GGA
• SC = final volume of seeded GGA (160 mL)
Example:
• C = 250 mg/L BOD
• B = 120 mg/L BOD
• SA = 20 mL
• SC = 160 mL
BOD (mg/L) = 250 mg/L - [120 mg/L x (20 mL÷160 mL)]
BOD mg/L = 235 mg/L
The GGA result is 235 ± 11 mg/L BOD.
Section 9 Typical curves
Refer to the expanded version of the manual for information about
specific procedures.
Figure 3 shows typical curves through a 10 day test period. For incorrect
curves, refer to Figure 4 on page 18.
Figure 3 Typical curves
1 Typical with substrate variation 3 Typical with time lag
2 Typical
Section 10 Special considerations
10.1 Sample dilution
Unknown sample BOD effluent is typically in the 0 to 70 mg/L range.
Unknown sample BOD influent is typically in the 0 to 700 mg/L range.
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