Over deze norm
1.1 This test method is applicable to determine the pH of water samples with a conductivity of 2 to 100 μS/cm over the pH range of 3 to 11 and is frequently used in power generation low conductivity samples. pH measurements of water of low conductivity are problematic. Specifically, this test method avoids contamination of the sample with atmospheric gases and prevents volatile components of the sample from escaping. This test method provides for pH electrodes and apparatus that address additional considerations discussed in . This test method also minimizes problems associated with the sample''s pH temperature coefficient when the operator uses this test method to calibrate an on-line pH monitor or controller (see ).
1.2 This test method covers the measurement of pH in water of low conductivity with a lower limit of 2.0 μS/cm, utilizing a static grab-sample procedure where it is not practicable to take a real-time flowing sample.
Note 1: Test Method for on-line measurement is preferred over this method whenever possible. Test Method is not subject to the limited conductivity range, temperature interferences, potential KCl contamination, and time limitations found with this method.
1.3 For on-line measurements in water with conductivity of 100 μS/cm and higher, see Test Method .
1.4 For laboratory measurements in water with conductivity of 100 μS/cm and higher, see Test Method .
1.5 The values stated in SI units are to be regarded as standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
|Engelse titel||Standard Test Method for pH Measurement of Water of Low Conductivity|