GB/T 6904-2026 Determination of pH in water for industrial recirculating cooling system and boiler English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 6904-2026
Determination of pH in water for industrial recirculating cooling system and boiler
工业循环冷却水及锅炉用水中pH的测定
Issue date: 2026-02-27 Implementation date: 2026-09-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents or materials
6 Apparatus
7 General requirements
8 Test procedure
9 Reporting of results
10 Permissible tolerance
Determination of pH in industrial circulating cooling water and boiler water
1 Scope
This document describes the method for the determination of pH in industrial circulating cooling water and boiler water.
This document is applicable to the determination of pH in industrial circulating cooling water and boiler water in the range of 0 to 14, and is also applicable to the determination of pH in natural water and wastewater.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 603, Chemical reagent — Preparations of reagent solutions and indicator solutions used in test methods
GB/T 6682-2008, Water for analytical laboratory use — Specification and test methods
GB/T 6907, Methods for analysis of water for boiler and for cooling — Sampling method for water samples
GB/T 27501-2011, Preparation method of buffer solutions for the measurement of pH
3 Terms and definitions
No terms and definitions are required to be defined in this document.
4 Principle
An indicating electrode and a reference electrode, or a combination electrode, are immersed in the same test solution, forming a galvanic cell. Its electromotive force conforms to the Nernst equation with respect to the pH of the solution. The pH of the solution is obtained by measuring the electromotive force of the galvanic cell.
5 Reagents or materials
Unless otherwise specified, the reagents and water used in this document shall be of analytical grade and Grade 3 water in accordance with GB/T 6682-2008. Unless otherwise specified, the reagents and preparations required for the tests shall be prepared in accordance with GB/T 603.
5.1 Carbon dioxide-free water.
5.2 Potassium tetraoxalate standard buffer solution: c[KH₃(C₂O₄)₂·2H₂O] = 0.05 mol/L. Prepare in accordance with 5.3.2 a) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.3 Potassium hydrogen tartrate standard buffer solution: saturated solution at 25 °C. Prepare in accordance with 5.3.2 b) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.4 Potassium hydrogen phthalate standard buffer solution: c(KHC₈H₄O₄) = 0.05 mol/L. Prepare in accordance with 5.3.2 c) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.5 Mixed phosphate standard buffer solution: c(KH₂PO₄) = 0.025 mol/L; c(Na₂HPO₄) = 0.025 mol/L. Prepare in accordance with 5.3.2 d) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.6 Sodium tetraborate standard buffer solution: c(Na₂B₄O₇·10H₂O) = 0.01 mol/L. Prepare in accordance with 5.3.2 e) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.7 Calcium hydroxide standard buffer solution: saturated solution at 25 °C. Prepare in accordance with 5.3.2 f) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
Note: Commercially available pH standard buffer solutions typically have pH values close to 4, 7 and 10. The specific pH and usage temperature are provided by the supplier and shall be used in accordance with the instructions.
Standard
GB/T 6904-2026 Determination of pH in water for industrial recirculating cooling system and boiler (English)
Standard No.
GB/T 6904-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
6500 words
Translation Price(USD)
195.0
Implemented on
2027-2-1
Delivery
via email in 1~3 business day
Detail of GB/T 6904-2026
Standard No.
GB/T 6904-2026
English Name
Determination of pH in water for industrial recirculating cooling system and boiler
GB/T 6904-2026 Determination of pH in water for industrial recirculating cooling system and boiler English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 6904-2026
Determination of pH in water for industrial recirculating cooling system and boiler
工业循环冷却水及锅炉用水中pH的测定
Issue date: 2026-02-27 Implementation date: 2026-09-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents or materials
6 Apparatus
7 General requirements
8 Test procedure
9 Reporting of results
10 Permissible tolerance
Determination of pH in industrial circulating cooling water and boiler water
1 Scope
This document describes the method for the determination of pH in industrial circulating cooling water and boiler water.
This document is applicable to the determination of pH in industrial circulating cooling water and boiler water in the range of 0 to 14, and is also applicable to the determination of pH in natural water and wastewater.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 603, Chemical reagent — Preparations of reagent solutions and indicator solutions used in test methods
GB/T 6682-2008, Water for analytical laboratory use — Specification and test methods
GB/T 6907, Methods for analysis of water for boiler and for cooling — Sampling method for water samples
GB/T 27501-2011, Preparation method of buffer solutions for the measurement of pH
3 Terms and definitions
No terms and definitions are required to be defined in this document.
4 Principle
An indicating electrode and a reference electrode, or a combination electrode, are immersed in the same test solution, forming a galvanic cell. Its electromotive force conforms to the Nernst equation with respect to the pH of the solution. The pH of the solution is obtained by measuring the electromotive force of the galvanic cell.
5 Reagents or materials
Unless otherwise specified, the reagents and water used in this document shall be of analytical grade and Grade 3 water in accordance with GB/T 6682-2008. Unless otherwise specified, the reagents and preparations required for the tests shall be prepared in accordance with GB/T 603.
5.1 Carbon dioxide-free water.
5.2 Potassium tetraoxalate standard buffer solution: c[KH₃(C₂O₄)₂·2H₂O] = 0.05 mol/L. Prepare in accordance with 5.3.2 a) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.3 Potassium hydrogen tartrate standard buffer solution: saturated solution at 25 °C. Prepare in accordance with 5.3.2 b) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.4 Potassium hydrogen phthalate standard buffer solution: c(KHC₈H₄O₄) = 0.05 mol/L. Prepare in accordance with 5.3.2 c) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.5 Mixed phosphate standard buffer solution: c(KH₂PO₄) = 0.025 mol/L; c(Na₂HPO₄) = 0.025 mol/L. Prepare in accordance with 5.3.2 d) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.6 Sodium tetraborate standard buffer solution: c(Na₂B₄O₇·10H₂O) = 0.01 mol/L. Prepare in accordance with 5.3.2 e) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
5.7 Calcium hydroxide standard buffer solution: saturated solution at 25 °C. Prepare in accordance with 5.3.2 f) of GB/T 27501-2011. Commercially available pH standard buffer solutions may also be purchased.
Note: Commercially available pH standard buffer solutions typically have pH values close to 4, 7 and 10. The specific pH and usage temperature are provided by the supplier and shall be used in accordance with the instructions.
