YSI 52 - Manual (Page 32)

Discussion of Measurement Errors Section 9
2. Probe nonlinearity error: ±0.3% of reading
3. The variation from nominal response to sample temperature is ±0.2% of the DO
reading per degree C of the temperature difference between the temperature of the
sample and the temperature at which the probe was calibrated.
9.3 TYPE 3 ERRORS - CALIBRATION
1. Sample temperature uncertainty error: ±1% of reading
This error is zero when calibrating in the % air saturation mode or when
calibrating to a Winkler titration sample.
2. Error due to barometric pressure uncertainty of 13mm Hg: ±1.7% of reading
3. Error due to altitude estimation uncertainty of 500 ft: ±1.8% of reading
9.4 ERROR CALCULATION EXAMPLE
The example given presumes that air calibration is used. If the Winkler titration
calibration method is used, type 3 errors are replaced by the uncertainty attributable to
the overall Winkler determination. This example is for an extreme combination of
conditions.
Calibration conditions:
method: air calibration
temperature: 24°C
altitude: 600 feet
calibrated to: 8.24 mg/L
Measurement conditions:
temperature: 20°C
reading: 7.26 mg/L
mode: mg/L
YSI, Incorporated Model 52 28