GB/T 5750 "Standard Examination Methods for Drinking Water" is divided into the following parts:
——General Principles;
——Collection and Preservation of Water Samples;
——Water Analysis Quality Control:
——Organoleptic and Physical Parameters;
——Nonmetal Parameters;
——Metal Parameters;
——Aggregate Organic Parameters;
——Organic Parameters;
——Pesticides Parameters;
——Disinfection by-products Parameters;
——Disinfectants Parameter;
——Microbiological Parameters;
——Radiological Parameters
Part 1 Standard Examination Methods for Drinking Water-General Principles
1 Scope
This standard specifies the basic principles and requirements of water quality examination for drinking water.
This standard is applicable to the water quality examination of drinking water, is also applicable to the water quality examination of source water and processed, stored and delivered drinking water.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this national standard. For dated reference, subsequent modification to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest edition of these documents is applicable. For undated references, the latest edition of the normative document is applicable to this standard.
GB 5749 "Sanitary Standard for Drinking Water"
GB/T 6682 "Water for Laboratory Use-Specifications"(GB/T 6682-1992, neq ISO 3696: 1987)
GB 15603 "Rule for Storage of Chemical Dangers"
GB 19489 "Laboratories-General Requirements for Biosafety"
JJG 196 "Verification Regulation of Working Glass Container"
3 Terms and Definitions
The following terms and definitions are applicable to this standard.
3.1 Constant weight
It refers that the mass difference after continuous twice drying is below 0.2mg except total solubility solid.
3.2 Measure
It refers to adopting water sample or test solution with measuring cylinder.
3.3 Pipet
It refers to sucking with no-scale division suction pipet or scale division suction pipet (pipet).
3.4 Constant volume
It refers to the operation using pure water or other solvent to dilute to scale in the volumetric flask.
3.5 Reference solution
The listed items of this standard method shall take the blank solvent (pure water or organic solvent) as the reference except as otherwise herein provided.
4 Selection of Examination Methods
4.1 If the same item has two or more than two examination methods, it may be selected according to equipment and technical conditions, but the first law shall be the arbitration law.
4.2 Minimum detectable mass: the accurately measured minimum mass.
4.3 Minimum detectable mass concentration: corresponding concentration of minimum detectable mass.
4.4 The precision and accuracy are qualitative concept, which should not be expressed with fixed quantity, and the "uncertainty" shall be used for all expressed with quantity value. Presently, it is the transition stage of promoting to adopt uncertainty in domestic. This standard connects with previous data, and continues to adopt precision and accuracy, specific parameter adopting standard deviation, relative standard deviation and recovery rate.
5 Reagents and Concentration Expression
5.1 Reagent specification: all used reagents in this standard shall be analytically pure (AR) class if no specification indication. If other specifications are needed, it shall be explained separately, but the indicator and organism dye do not distinguish specification.
5.2 The calibration standard shall be adopted with certificated standard solution and prepared according to standard method by adopting certificated standard reference.
5.3 If the reagent solution is not indicated to prepare with which solvent, it refers to preparing with pure water.
5.4 All used hydrochloric acid, sulfuric acid and ammonia of this standard shall be concentrated reagents, which are expressed with HCl (ρ20=1.19g/mL), H2SO4 (ρ20=1.84g/mL).The reagent concentration after preparation shall be expressed with mol per liter (mol/L).
5.5 The preparation methods of all reagents are illustrated in each item, and Table 1 is the concentration of several common acid and alkali and formula of diluted solution preparation.
