Foreword
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This document is developed in accordance with the rules given in GB/T 1.1-2020 Directives for standardization - Part 1: Rules for the structure and drafting of standardizing documents.
This document is Part 13 of GB/T 5750 Standard examination methods for drinking water. The following parts of GB/T 5750 have been issued:
——Part 1: General principles;
——Part 2: Collection and preservation of water samples;
——Part 3: Water analysis quality control;
——Part 4: Organoleptic and physical indices;
——Part 5: Inorganic nonmetallic indices;
——Part 6: Metal and metalloid indices;
——Part 7: Aggregate organic indices;
——Part 8: Organic indices;
——Part 9: Pesticides indices;
——Part 10: Disinfection by-products indices;
——Part 11: Disinfectants indices;
——Part 12: Microbiological indices;
——Part 13: Radiological indices.
This document replaces GB/T 5750.13-2006 Standard examination methods for drinking water - Radiological parameters. In addition to structural adjustment and editorial changes, the following main technical changes have been made with respect to GB/T 5750.13-2006:
a) The clause "Terms and definitions" has been added (see Clause 3 hereof);
b) Two examination methods have been modified (see 4.1 and 5.1 hereof; 1.1 and 2.1 of Edition 2006);
c) Three examination methods have been added (see 6.1, 7.1 and 7.2 hereof).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This document was proposed by and is under the jurisdiction of the National Health Commission of the People's Republic of China.
The previous editions of this document are as follows:
——This document was firstly issued as GB/T 5750-1985 in 1985 and first revised as GB/T 5750.13-2006 in 2006;
——This is the second revision.
Introduction
The series of standards GB/T 5750 Standard examination methods for drinking water, as the recommended national standards for drinking water examination technology, are compatible with GB 5749 Standards for drinking water quality, and are also served as an important technical support of GB 5749. They provide examination methods for implementing GB 5749 and carrying out hygienic safety evaluation of drinking water.
GB/T 5750 consists of 13 parts.
——Part 1: General principles. It provides the basic principles and requirements for water quality examination.
——Part 2: Collection and preservation of water samples. It provides the basic principles, measures and requirements of water sample collection, preservation, management, transportation and sampling quality control.
——Part 3: Water analysis quality control. It provides quality control requirements and methods for water quality examination and testing laboratories.
——Part 4: Organoleptic and physical indices. It provides corresponding examination methods for organoleptic and physical indices.
——Part 5: Inorganic nonmetallic indices. It provides corresponding examination methods for inorganic nonmetallic indices.
——Part 6: Metal and metalloid indices. It provides corresponding examination methods for metal and metalloid indices.
——Part 7: Aggregate organic indices. It provides corresponding examination methods for aggregate organic indices.
——Part 8: Organic indices. It provides corresponding examination methods for organic indices.
——Part 9: Pesticides indices. It provides corresponding examination methods for pesticides indices.
——Part 10: Disinfection by-products indices. It provides corresponding examination methods for disinfection by-products indices.
——Part 11: Disinfectants indices. It provides corresponding examination methods for disinfectants indices.
——Part 12: Microbiological indices. It provides corresponding examination methods for microbiological indices.
——Part 13: Radiological indices. It provides corresponding examination methods for radiological indices.
Standard examination methods for drinking water - Part 13: Radiological indices
1 Scope
This document describes the methods for determination of gross α radioactivity concentrations, gross β radioactivity concentrations, mass concentrations of uranium, and activity concentrations of 226Ra in drinking water and water sources.
This document is applicable to the determination of gross α radioactivity concentrations of α radionuclides (excluding volatile nuclides under the conditions specified in this document), gross β radioactivity concentrations of β radionuclides (excluding volatile nuclides under the conditions specified in this document), mass concentrations of uranium and activity concentrations of 226Ra in drinking water and water sources. This document may serve as a reference to the determination of gross α radioactivity, gross β radioactivity, uranium and 226Ra in saline and mineralized water.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 5750.1 Standard examination methods for drinking water - Part 1: General principles
GB/T 5750.2 Standard examination methods for drinking water - Part 2: Collection and preservation of water samples
GB/T 5750.3 Standard examination methods for drinking water - Part 3: Water analysis quality control
GB/T 5750.6-2023 Standard examination methods for drinking water - Part 6: Metal and metalloid indices
GB/T 11682 Low background alpha and/or beta measuring instruments
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 5750.1, GB/T 5750.2 and GB/T 5750.3 apply.
4 Gross α radioactivity
4.1 Detection method for low background gross α
4.1.1 Method and principle
Acidify the water sample, evaporate and concentrate it to convert it into sulfate, evaporate it until the sulfuric acid smokes, and burn it at 350℃. After transferring the residue to the sample tray to make the sample source, conduct immediately gross α measurement. Calculate the activity concentration of gross α radioactivity in water by measuring α standard source calibration. For this method, there are three measurement methods available: effective thickness method, comparison method and thick source method, see 4.1.8.1, 4.1.8.2 and 4.1.8.3 for details.
For this method, the detection limit depends on the amount of inorganic salts in water sample, counting efficiency of the instrument, background count rate, counting time and other factors, which is about 0.02Bq/L.
4.1.2 Reagents
Unless otherwise specified, the reagents shall all be analytically pure agents complying with the national standard, and the water for test shall be deionized water or distilled water. There shall be no significant difference between the radioactive background counts of all reagents and those of instruments.
4.1.2.1 Nitric acid (HNO3): ρ20=1.42g/mL, [ω(HNO3)=65%].
4.1.2.2 Nitric acid solution: measure 100mL of nitric acid and dilute it to 200mL.
4.1.2.3 Sulfuric acid (H2SO4): ρ20=1.84g/mL.
4.1.2.4 Acetone (CH3COCH3).
4.1.2.5 Anhydrous ethanol (CH3CH2OH).
4.1.2.6 Calcium sulfate (CaSO4): guaranteed reagent. Some calcium salts may contain trace 226Ra and/or 210Pb, and it shall be verified that the calcium salts do not contain α radionuclides.
Foreword I
Introduction III
1 Scope
2 Normative references
3 Terms and definitions
4 Gross α radioactivity
5 Gross β radioactivity
6 Uranium in drinking water
7 226Ra in drinking water
