Simplified Procedure - Hach BODTrak II User Manual

Use the applicable sample volume tables for each procedure.
If power is interrupted when the instrument is in DELAY status, the
test will stop and the status will change to CLEAR when power
returns. Start the test again. If power is interrupted when the
instrument is in RUN status, the test will resume when power returns.
Keep deionized water overnight in an incubator at 20 ºC. Shake the
deionized water to saturate with air.
Let the seed become stable overnight in the BOD incubator at a
temperature of 20 ºC. Be careful not to disturb the settled solution.
Pipet seed solution from the top.
Dilution is necessary if samples have BOD values more than
700 mg/L.
At elevations higher than 5000 feet above sea level, the 0 to 35 mg/L
BOD range is decreased to 0 to 25 mg/L BOD. Adjustment is not
necessary for other test ranges.
Refer to Special considerations
considerations including sample seeding and pretreatment.
Use only BODTrak II stir bars and bottles. These items are made
specifically to be used with the BODTrak II.

7.2 Simplified procedure

Items to collect:
• BODTrak II bottle
• Thermometer
• Blender (optional)
• Graduated cylinder
• Nutrient buffer pillow (1x)
Use the correct sample volume for the BOD range as shown in
10 English
on page 15 for special
Table
Table 4 Simplified sample volumes
BOD range (mg/L)
0 to 35
0 to 70
0 to 350
0 to 700
1. Heat or cool the
sample to 19 to
21 ºC.
4.
Sample volume (mL)
420
355
160
95
2. Homogenize the 3. Select the correct
sample in a blender sample volume for
if it contains large the BOD range
settleable or (Table
floatable solids. the sample into a
graduated cylinder.
4). Measure