DOC316.53.01179 Ed8.pdf - Oxygen Dissolved DOC316.53.01179...

Oxygen, Dissolved
DOC316.53.01179
Azide Modification of Winkler Method Method 8215 and 8332
1 to more than 10 mg/L Digital Titrator
Scope and application: For water, wastewater and seawater.
Test preparation
Before starting
As an alternative to stirring by hand, use the TitraStir Titration Stand to hold the Digital Titrator and stir the sample.
Review the Safety Data Sheets (MSDS/SDS) for the chemicals that are used. Use the recommended personal protective
equipment.
Dispose of reacted solutions according to local, state and federal regulations. Refer to the Safety Data Sheets for disposal
information for unused reagents. Refer to the environmental, health and safety staff for your facility and/or local regulatory
agencies for further disposal information.
Items to collect
Description Quantity
Digital Titrator 1
Delivery tube for Digital Titrator, J-hook tip 1
Clippers for plastic pillows 1
For Method 8215, 300-mL BOD bottle
Dissolved Oxygen Reagent Set 1
Sodium Thiosulfate Titration Cartridge, 2.00 N varies
Bottle, with stopper, BOD, 300-mL 1
Cylinder, graduated, 250-mL 1
Flask, Erlenmeyer, 250-mL 1
For Method 8332, 60-mL BOD bottle
Dissolved Oxygen 1 Reagent Powder Pillows 1
Dissolved Oxygen 2 Reagent Powder Pillows 1
Dissolved Oxygen 3 Reagent Powder Pillows 1
Sodium Thiosulfate Titration Cartridge, 0.2000 N 1
Bottle, with stopper, BOD, 60-mL 1
Flask, Erlenmeyer, 125-mL 1
Beaker, polypropylene, 50-mL, low form 1
Refer to Consumables and replacement items on page 6 for order information.
1

Sample collection
Good sample collection and handling techniques are important to get correct results. The
dissolved oxygen content of the sample can change with depth, turbulence, temperature,
sludge deposits, light, microbial action, mixing, travel time and other factors. A single
dissolved oxygen test frequently is not an accurate reflection of the overall condition of a
body of water. Several samples taken at different times, locations and depths are
recommended for most reliable results.
• Collect samples in clean BOD Bottles.
• If prompt analysis is not possible, do steps 1 through 4 of the procedure and keep the
samples protected from light at 10 to 20 °C (50 to 68 °F).
• Pour a small quantity of water into the flared lip area of the stopper to seal the bottle.
• Use a BOD bottle cap on the flared lip.
• Keep samples for a maximum of 8 hours. For analysis start with step 5.
Method 8215, 300-mL BOD bottle
1. Collect a water sample in
a clean 300 ‑ mL BOD bottle.
Let the sample overflow the
bottle for 2 or 3 minutes to
make sure that a
representative sample is
collected.
2. Add the contents of one
Manganous Sulfate Powder
Pillow and one Alkaline
Iodide-Azide Reagent
Powder Pillow to the
sample.