iSAMI-pH - Inexpensive Ocean pH Sensor for Surface applications


The iSAMI-pH is based on the same technology as the larger, more expensive SAMI-pH, but is meant for use at the surface, for use on buoys, drifters, etc.

  • Measures pHT (total hydrogen scale) in the marine pH range of 7-9
  • Uses a highly accurate colorimetric reagent method
  • System does not suffer from the drift that plagues most electrode based pH probes
  • Designed to provide researchers with valuable in-situ time series data near the surface - depths to 3 m.
  • 160-day deployment capability (hourly measurements, 25C)
  • External battery package available, or power from buoy, drifter.



iSAMI-pH Performance Parameters

pH range  7-9
Salinity range* 25-40
Response time  3 minutes
Accuracy (based on CRM intercomparison)  +/- 0.01 pH units
Precision <0.003 pH units
Long term drift <0.002 pH units over 6 months
Thermistor accuracy, precision 0.1° C,  +/- 0.01º C
Dimensions -iSAMI / External battery  (length x diameter) 28 x 6.4 cm / 24 x 8.9 cm
Weight in air  - iSAMI/External battery  0.9 kg / 2.2 kg
* Extended range possible, please contact us with questions.