When finding strategic partners for business in a country other than your own there is a need to be assured that everything is under control. In search supplies in China, the task of supervision and inspection becomes more complicated, due to the peculiarities of that China has.
That is why we offer our services guiding on international standards.
Thanks to the inspection services we offer in Annex Asia you may know who you do business with in less than 4 days.
Generally performing these inspection services by your company or by yourself would impose an excessive hassle and cost, which will surely slow down the process of investment and cooperation with Chinese suppliers. For these reasons, from Annex Asia we help our clients in this process reaching all Mainland China, India, Thailand, Vietnam, Indonesia, Pakistan and Latin-America
When performing quality control services, it is important to understand the standard used for the selection of samples for visual appearance or review.
Most companies employ quality control for inspecting the product ISO 2859-1 (ANSI/ASQCZ1.4-2003), also known as standard tables AQL (Acceptance Quality Limit or Limit of acceptable quality).
Defects can be classified into three levels:
Critical: When the product is found to be unsafe, detrimental to the end user, and / or conflict with regulations.
Major: When the product exhibits failure that affects the performance and / or aesthetic considerable impact on the sale.
Low: When the failure does not significantly affect the aesthetics or functionality.
The first table indicates how the letter code is organized according to the quantities of the product. There are three levels I, II, and III. Level I is the least severe and level III is the most stringent. Level II is the standard and commonly is selected since it is also the QC listed companies. (Note: The customer may choose Level I or Level III). To fully understand the concept let's do an exercise. Suppose we have an order for 3000 units and the second is selected, then the code letter is "K".
The severity level can be recorded in the following table. Noted are the top levels ranging from 1 to 6.5; in most cases (standard) is 0% for critical defects, major defects to 2.5% and 4% for minor defects.
This example considers default 2.5% higher and 4.0% lower default. The sample number is 200 units, with a tolerance of 7 major and 10 minor defects.
This table lists the number of total units to the degree of thoroughness of the inspection. As we mentioned, the degree that is usually considered is Level II.
Special Levels S-1, S-2, S-3 and S-4 are special inspections in which small samples for special testing (eg Hi-Pot test, Seam testing) are selected. In some cases, the samples cannot be re-used or tests take too much time in doing. The level of severity ranging from S-1 (least severe) to S-4 (the most stringent).
The following table lists the number of samples to be taken depending on the stringency level selected. For example if the Level II for a total of 5000 units is selected, then we must take a sample of 200 units (sample size) and the degree of acceptance that usually states is 0% for critical errors, 2.5% for defects older and 4% for minor defects. At the top we see the acceptance for which we will consider only from 0.010 to 6.5. If the margin for error is greater than 2.5%, then the amount of errors allowed is 10 units (Ac). From 11 Units is rejected (Re). For minor defects the accepted amount of 14 units.
To visualize the difference in sample size, suppose we have a total of 5000 units. We can see the number of samples must be selected according to the rigor.