Hach-Lange BODTRAK II: Respirometric Biochemical Oxygen Demand (BOD) - Manual (Page 22)

BODTrak™ II procedures
22
5.3 Hach GGA (glucose/glutamic acid) procedure
Required apparatus:
BODTrak II bottle
Graduated cylinder
Volumetric pipet and pipet filler
Tensette ® pipet and pipet tips
Wash water bottle
Ampule breaker
Required reagents:
Deionized water
Hach GGA solution
1 nutrient buffer pillow
Before starting the test:
Use Hach BOD Standard Solution Ampules for Manometric Method (3000 mg/L Glucose,
3000 mg/L Glutamic acid).
On a standard containing 150 mg/L each of glucose and glutamic acid, a single analyst
using 6 BODTrak II instruments and testing 44 samples obtained a mean of 235 mg/L BOD
with a 95% Confidence Limit of Distribution of 11 mg/L or a range of 224 to 246 mg/L BOD
after 5 days.
Always prepare the seed blank before the GGA samples. Use the same amount of seed for
all GGA samples and seed blank.
Refer to section 5.7 on page 33 for special considerations.
Prepare seed blank
Use steps 1, 3 to 7.
Prepare sample
Use steps 1 to 7.