Table 2.

Comparison of the pH/Oxygen planar optode and electrodes for pH measurements. AE: absolute error; RE: relative error; SD: standard deviation.

pH Electrodes	pH/Oxygen Planar Optode
Measured	Calculated	AE	RE	SD
4.23	3.92	0.31	7.32%	0.0462
4.89	4.63	0.26	5.32%	0.1487
5.56	5.80	0.24	3.72%	0.1292
6.45	6.27	0.18	2.79%	0.3043
7.75	7.45	0.3	3.87%	0.2945