In the BOD test example, what is the sample volume used?

In the BOD test example, what is the sample volume used?

• A. 4.0 mL
• B. 6.0 mL
• C. 8.0 mL
• D. 12.0 mL

Answer: (B)

In the BOD test, you fill a standard bottle to a fixed total volume by diluting the sample with dilution water. The sample volume chosen sets the dilution level so the oxygen demand falls within a readable range after incubation. In the typical example, you add 6.0 mL of the wastewater sample and dilute with 294.0 mL of dilution water to reach 300.0 mL total. That creates a 1:50 dilution, which keeps the measurement within the test’s usable range for the 5-day period. Using this exact 6.0 mL sample volume is standard practice to maintain consistency and allow accurate calculation of the BOD.

In the BOD test, you fill a standard bottle to a fixed total volume by diluting the sample with dilution water. The sample volume chosen sets the dilution level so the oxygen demand falls within a readable range after incubation. In the typical example, you add 6.0 mL of the wastewater sample and dilute with 294.0 mL of dilution water to reach 300.0 mL total. That creates a 1:50 dilution, which keeps the measurement within the test’s usable range for the 5-day period. Using this exact 6.0 mL sample volume is standard practice to maintain consistency and allow accurate calculation of the BOD.