What is a sampling test?

Nowadays, due to the continuous emergence of food safety problems, consumers are no longer trusting products as they used to, and how businesses can gain the trust of consumers is a very effective way to pass products through the Bureau of Quality Supervision and Inspection and other departments to meet standards. The goods will naturally regain the trust of consumers. The most commonly used method for quality inspection is the sampling inspection. What is the following sample detection?

Sampling inspection, referred to as inspection, refers to randomly sampling some of the unit products from a batch of N batches of products, then testing each product in the sample according to the product quality characteristics, and judging the product according to the sample inspection results. The process of passing the batch or not.

First, the sampling test is suitable for:

(1) When the product volume is large.

(2) When there are many inspection items.

(3) When the test is destructive or damaging.

(4) The inspection cost per unit product is high or the working hours are long.

Second, the sample inspection has the following characteristics:

(1) According to the sampling plan determined in advance, the sample of the unit product shall be taken from the product lot and tested, and the sample inspection result shall be compared with the criterion for the approval of the batch to judge whether the batch of the product is qualified or unqualified.

(2) Sampling inspections have the wrong judgment risk.

(3) The sample as a representative of the batch should be able to extract from the product with equal probability.

(4) There should be clear criteria and sampling inspection procedures and programs. No matter who is the inspector, it should be done in the same way.

(5) Unqualified products may still be allowed in inspection-qualified batches, but also in batches in which the inspection is judged to be unqualified, and qualified products may be in the majority.

Sampling inspections apply to more average, frequently used materials. Usually the factory uses this inspection method. According to its type, sampling inspection can be divided into the following categories:

1. Type-based sampling inspection.

The type-based sampling inspection is to judge whether the inspection and approval batch is qualified under the premise of balancing the interests and losses of the supply and demand sides.

2. Acceptance Level (AQL).

Acceptable quality level (AQL) is a defective product rate acceptable to both parties, and is denoted by the symbol AQL. Types applicable to the AQL type sampling plan are: when continuously purchasing same-type goods from different suppliers; when the delivery is judged to be unqualified and the loss of the supplier is large; the batch of qualified standards should be accepted as much as possible.

3. Adjusted sampling inspection.

Adjusted sampling inspection shall be based on the past performance of the supplier and the inspection results of the batch: normal inspection, strict inspection and decrement inspection.

4. Continuous production type sampling inspection.

Continuous production type sampling inspection is applicable to the inspection type when a large number of continuously produced products and materials continuously flow.

5. Selection type sampling inspection.

Selective type sampling inspection shall be carried out on all batches that are judged to be unqualified, and the rejected products after the full inspection shall be returned to the supplier for replacement of the same quantity of good products.

Sampling test related explanations:

1. Unit product: The basic unit that makes up the product.

2. Sample size: The number of unit products contained in the sample, generally denoted by n.

3. Quality product representation method: counting and metering

4. Unqualified and defective products

(1) Unqualified: The quality characteristics of a unit product deviate from the technical standards (norms), that is, it does not meet the requirements.

According to the importance of the quality characteristics of the unit product, some industries can be classified as Class A unqualified, Class B unqualified and Class C unqualified.

Type A failure: The very important quality characteristics of a unit product do not conform to the regulations or the important quality characteristics are extremely inconsistent with the regulations.

Type B unqualified: The important quality characteristics of the unit product do not meet the requirements or the quality characteristics do not meet the requirements.

Category C failed: The general quality characteristics of the unit product did not meet the requirements or the quality characteristics did not meet the requirements.

And some industries can be divided into A-level unqualified, B-level unqualified, C-level unqualified and D-level unqualified.

A very serious failure score of 100 points

Grade B serious unqualified score 50 points

Grade C Medium Severe Failed Score 10 points

Grade D is not severe failure score 1 point

(2) Nonconforming product: One or more unqualified unit products.

According to the degree of unqualified weight, it can be divided into Class A unqualified product, Class B unqualified product and Class C unqualified product.

5. Check batch and batch

(1) Inspection lot: Unit products that are collected for the purpose of sampling inspection, abbreviated as batch.

(2) Batch: The number of unit products contained in a batch, that is, the total number of unit products contained in a batch of products submitted for inspection, denoted by N.