GB/T 6678-2003General principles for sampling chemical products (English PDF)

4.1 Purposes in technical aspect

4.2 Purposes in business aspect

4.3 Purposes in law aspect

4.3.1 To check whether the material meets the statutory requirements;

4.3.2 To check whether the leakage of hazardous substances in the production process exceeds the allowable limit;

4.4 Purposes in safety aspect

4.4.1 To determine whether the material is safe or dangerous;

6.1 Factors influencing the sampling plan

6.1.1 The nature, physical state and range of the overall material to be collected. The range can be a certain delivery batch agreed by the purchaser and supplier, or a certain production batch produced intermittently; and in the case of continuous production, it can be the material produced within a certain time interval;

6.1.6 Precision of the detection method;

6.1.7 Value of the material;

6.1.8 Possibility to simplify sampling operations […]

6.2 Basic content of sampling plan

6.2.1 Determine the range of the overall material;

6.2.2 Determine the sampling unit and the secondary sampling unit;

6.2.5 Specify the processing method of the sample;

6.2.6 Specify sampling safety measures […]

7.1 Sampling error

7.1.1 Sampling random error

Sampling random error is the deviation caused by some uncontrollable accidental factors in the sampling process, which cannot be avoided. Increasing the number of sampling repetitions can reduce such error.

7.2 Variability types of material characteristic values

Materials can be divided into two types according to the variability of characteristic values, namely uniform materials and non-uniform materials. Non-uniform materials can be subdivided as follows. […]

7.3 Variability of overall material characteristic values and inference of their types

The variability of the overall material characteristic values and their types are the basis for designing a sampling plan. They exist objectively, but it is expensive and difficult to operate to estimate them through the detected data. Therefore, the actual measurement is generally not carried out when designing the sampling plan, but inferences and assumptions are made based on experience and the material information that has been mastered.

7.4 Sampling of uniform material

7.5 Sampling of non-uniform materials

For the sampling of non-uniform materials, in addition to paying attention to the same two points as uniform materials, random sampling is generally adopted.

7.6 The number of samples and the quantity of samples

Under the premise of meeting the needs, the minimum number of samples and the minimum quantity of samples that can give the required information are the optimal number of samples and the optimal quantity of samples.

7.6.1 The number of samples

For general chemical products, multi-unit materials can be used for processing. Its unit boundaries may be tangible, such as a container; or imagined, such as a specific time interval for flowing material.

7.6.2 The quantity of samples

On the premise of meeting the needs, the quantity of samples shall at least meet the following requirements.

7.6.2.1 At least meet the requirements of three repeated inspections;

7.6.2.2 When it is necessary to keep the test-prep samples, the requirements for the test-prep samples shall be met;

10.1 Sample container

10.2 Sample label

10.2.1 The name and serial number of sample;

10.2.5 The quantity of sample;

10.2.6 Sampling date

10.2.7 Samplers, etc. […]

10.3 Saving and withdrawing of samples

The product sampling method standard or sampling operation procedure shall stipulate the storage amount of the sample (as a test-pre sample), storage environment, storage time and withdrawal method. […]