4 hach standard method procedure – Hach-Lange BODTRAK II: Respirometric Biochemical Oxygen Demand (BOD) User Manual

Page 24

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BODTrak™ II procedures

24

5.4 Hach Standard Method procedure

Required apparatus:

Thermometer

BODTrak II bottle

Blender (optional)

Graduated cylinder

Tensette pipet and pipet tips

Wash water bottle

Required reagents:

1 nutrient buffer pillow

Additional nutrient or buffer (optional)

Deionized water

Before starting the test:

Use the sample volume table to choose the correct sample size (

Table 6

).

If seeding samples, prepare a seed blank before preparing a sample. Treat the seed blank

the same as any other sample and omit step 5.

Refer to

section 5.7 on page 33

for special considerations.

Table 6 Hach Standard Method sample volumes

BOD range

(mg/L)

Sample

volume (mL)

Seed volume

(mL)

Final volume

(mL)

Dilution

factor

0 to 35

370

10 to 35

420

1.14

0 to 70

305

10 to 35

355

1.16

0 to 350

110

10 to 35

160

1.45

0 to 700

45

10 to 35

95

2.11

Note: If seed strength is unknown, use 20 mL. Adjust seed volume as necessary to achieve
optimum results.

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