YSI ProDSS Meter Calibration and Maintenance
K:\Streamkeepers\Monitoring\Eqpt & supplies\Calibration-Maintenance\SOPs\YSI ProDSS maint-
cal SOP's
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water
6.
Set the unit aside right side up and wait 5 to 15 minutes for complete air saturation in the cup
chamber.
7.
Select the
calibration button
, then select DO, then DO%.
8.
Confirm stabilization by watching the
actual readings
on the screen, if DO% and Temp
remain within ± 0.1 for 2 minutes, the sensor is stable.
9.
After observing stabilization, press Accept Calibration. “Calibration Successful!” will be
displayed on the screen.
NOTE:
If you see a calibration error message, verify the barometer reading and inspect the
sensor cap. Clean and/or replace the sensor cap as needed (see the
Maintenance
section
below).
DO Calibration Check (Winkler side-by-side)
DO calibration is done in the lab just prior to, and, at the end of each sampling event. We test the
validity of this calibration at the beginning and end of each quarter by doing a side-by-side
Winkler titration. Proof of the validity of the meter’s DO calibration is essential to acceptance of
our data by the State.
Equipment needed:
•
1 or 2 large plastic bucket(s) - depends on method used below
•
DI water from lab
•
“DO/Barometer Calibration Protocol & Data Sheets” notebook
•
Blank DO calibration sheet
•
YSI ProDSS meter
•
Purified water, lint-free tissues for cleaning
•
Aquarium air pump and aeration stone
First prepare the 100% oxygenated water in the lab:
Method 1
1.
Fill one of the buckets with DI water in the lab
2.
Pour this water into the other bucket and repeat 20 times
3.
Let this water sit with a lid on it until the following day. If the temperature does not change,
it will stabilize and remain at 100% oxygenation
Method 2 (preferred)
4.
Fill a bucket with DI water in the lab
5.
Place the aeration stone on the bottom of the bucket and turn on pump
6.
Loosely cover the bucket and set aside for approximately 24 hours
Preparing Winkler samples:
1.
Put on safety equipment: goggles, gloves, apron
2.
Take out BOD bottle #1 and fill it with the air saturated water previously prepared - fill to
neck, a clean beaker can be used to transfer water from the sample bucket you prepared
earlier
3.
Put on the glass stopper.
4.
The BOD bottles need to have the DO stabilized as they are collected immediately by adding
two chemicals as follows:
