General
pH value	4,005
Deviation	± 0,008
Bottle content	25 ml
Number of vials per pack	10

The COFRAC-certified pH buffer solution pH 4.005 from Chauvin Arnoux serves as reference material for the calibration and testing of pH measuring devices. The solution is directly traceable to the primary pH calibration standard of the French testing laboratory LNE and complies with the requirements of DIN standard 19266 as well as the recommendations of NIST and IUPAC. It ensures precise and traceable adjustment of the measuring electrode/measurement device pair, thereby maintaining the accuracy of measurement results over time. The buffer solution is packaged in single-use vials, each containing 25 ml, ensuring a fresh, uncontaminated solution for each calibration.

Applications
This pH buffer solution is specifically designed for the regular calibration of pH meters. It is used to check the function of the measuring electrode, compensate for aging effects, and ensure traceability of measurement results. The solution is suitable for laboratory and industrial applications where high measurement accuracy and documentation are required. The use of COFRAC-certified reference materials is particularly important in sectors with strict quality requirements, such as the food industry or pharmaceutical manufacturing.

Functions and Equipment in Detail
The pH buffer solution pH 4.005 has a defined pH value of 4.005 at 25 °C with an allowable deviation of ± 0.008. The solution is supplied in 25-ml vials, with the package containing 10 units. The packaging is designed to dispense each dose individually, preventing contamination and mixing. The color coding of the vials supports unambiguous identification of the respective buffer solution.

Technology Explained Simply
The traceability of measurement results is ensured by direct connection to the national primary standard of LNE. The COFRAC accreditation confirms that the production and certification of the buffer solution meet international standards. The pH values are defined at a temperature of 25 °C, which represents standard conditions for calibration. The low uncertainty of ± 0.008 ensures high accuracy when setting the measuring device.

Compatibility and Accessories
The buffer solution is designed for use with pH measuring devices that require calibration with reference solutions. It is part of a series of COFRAC-certified buffer solutions, which also include the values pH 6.865 and pH 9.180. These can be used together to perform a complete calibration across the entire measurement range. The solution is delivered with a certificate as reference material, confirming traceability and accreditation.

Installation and Mounting
The buffer solution requires no mounting or installation. It is taken directly from the vial into the measuring device or into a suitable container for calibration. Use follows the instructions of the respective pH measuring device. The vials are intended for single use and should not be reused after opening.

Operational Advantages
The use of this COFRAC-certified buffer solution ensures high measurement accuracy and documentable results. The single-use vials prevent contamination and ensure consistent quality for each calibration. Certification by COFRAC and traceability to the LNE primary standard increase the acceptance of measurement results in certified environments. The shelf life is 36 months before opening, providing long-term stability and planning security.