Regulations & pH Meters
1. Japanese Industrial Standards
In addition to the JIS regarding electrodes, and that covering measurement methods, there are others that also relate to pH meters. A typical example is the JIS for “Methods for measurement of industrial wastewater.”
JIS for devices used for continuous automatic pH measurement have also been established in recent years.
JIS Z 8802: Methods for determination of pH of aqueous solutions
JIS Z 8805: Glass electrodes for measurement of pH
JIS K 0102: Testing methods for industrial wastewater
JIS K 0802: Recording pH Meters
JIS K 2190: Fuel ethanol
2. Laws relating to measurement
In order to improve the reliability of pollution measuring equipment, the Ministry of Economy, Trade and Industry (the former Ministry of International Trade and Industry) revised part of the law regarding measurement in 1972. As a result of this revision, in addition to the conventional weighing equipment already included, the use of 17 types of concentration meters was also legally recognized. The glass-electrode pH meter was one of these newly included concentration meters.
(1) pH meters to be inspected
Glass-electrode hydrogen ion concentration meters are designated as requiring inspection because they are classified as being of the glass-electrode type. The detection element (electrodes) and display section of the device are inspected separately. pH meters other than the glass-electrode type are not subject to inspection.
(2) Applications of approved pH meters
For business or certification, only approved glass-electrode pH meters may be used. That is to say, it is strictly stipulated that only glass-electrode pH meters that have been approved through inspection may be used for purposes such as reporting to administrative organizations, certification work of analysis centers, and quality labeling.
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