GB/T 258-2025Determination of acidity of light petroleum products (English PDF)

3 Terms and definitions

4 Outline of the method

5 Reagents and materials

6 Apparatus and equipment

7 Sampling

8 Preparation for the test

9 Test procedure

10 Quality control

11 Processing of the test data

12 Expression of the results

13 Precision

14 Test report

Foreword

This document was issued on 5 October 2025 by the State Administration for Market Regulation and the Standardization Administration of the People's Republic of China, and has been in force since 1 May 2026.

It replaces GB/T 258-2016.

The document is under the responsibility of the Standardization Administration of China.

Classification: ICS 75.160.20, CCS E 31.

About this edition

GB/T 258-2025 is the current edition. It was issued on 5 October 2025 and has been in force since 1 May 2026, replacing GB/T 258-2016.

GB/T 258-2016 has been superseded: a specification that still cites it is citing a withdrawn edition.

The interval between issue and effect is the transition period. It exists so that producers, laboratories and buyers can requalify products, revise procedures and use up documentation before the new text becomes the one that applies. The date on this page is the official one from the record of the Standardization Administration.

Classification and status

GB/T 258-2025 is classified under ICS 75.160.20, in the field of petroleum and related technologies. ICS is the International Classification for Standards, the same scheme used by ISO and by the national bodies of most countries, which is what allows a Chinese standard to be placed beside its foreign counterparts on subject rather than on number.

Its Chinese Standard Classification code is CCS E 31. CCS is the domestic scheme, a letter for the sector and two digits for the subject within it, and it is the code by which the standard is filed and searched in China.

The GB/T prefix marks a recommended national standard. It is not, in itself, law: it becomes binding when a contract names it, when a regulation or a mandatory standard refers to it, or when a producer declares conformity with it. In practice that covers most of the cases in which it will be read — a purchase specification, an inspection agreement or a certification scheme.

The document is under the responsibility of the Standardization Administration of China, which is the body that maintains it and that will answer a formal question about its interpretation.