Types of Sampling for Product QC


Meta description: Quality control is implemented in manufactured goods to ensure it meets the required standard. EC Global Inspection Company can solve every quality control challenge and provide the most appropriate supply chain management.

Keywords: quality control, product sampling, product quality

Types of Sampling for Product QC

Quality control is implemented in manufactured goods to ensure it meets the required standard. This has promoted healthy consumption, especially in the food and beverage industry. Manufacturers are less worried about customers' needs when a quality control strategy is in place. However, only some of these strategies are suitable for some companies. This is why most companies rely on the sampling plan since it has proven effective over time.

In sampling quality control, several techniques best apply to most companies. Thus, every company needs to identify the best type of sampling plan for them, which varies with goals, product type, and quantity. Meanwhile, some companies may employ two or more methods, depending on the scope of work. You need to understand the various available options to identify your best sampling method.

What is Quality Sampling?

Quality sampling is one of the most effective methods in determining the quality of a particular set of elements among many products. It is considered a less intensive and cost-effective method of measuring production quality. This method is most adopted because determining the quality of each product produced by a company seems unrealistic. It is much possible to make errors while cross-checking every single product.

Professionals typically handle product samples and determine the quality rate based on a set standard. The process is usually done in batches to minimize the possibility of making errors. Once a set of products is rejected, the whole production is considered unsafe for human consumption. Thus, quality sampling plays a role in satisfying both consumers and manufacturers.

Types of Quality Sampling

Several factors determine your choice of quality sampling. However, below are the three common types you may want to consider.

Incoming Quality Control

Incoming Quality Control (IQC) examines the quality of raw materials needed for a product before it is manufactured. This method is most applicable to companies that use a third-party manufacturer. It also applies to companies that import products from a foreign country. Since you do not have direct control over the manufacturing process, you want to ensure the same principles are followed across all batches.

Sometimes, suppliers allocate a portion of the production and packaging to a sub-supplier. They tweak the quality of the product by introducing new changes little by little. Thus, you can only identify them if you apply a quality control strategy. Meanwhile, some suppliers may use poor ingredients due to a lack of understanding of customers' cultural perspectives or language. However, Incoming Quality Control helps to solve these barriers.

If your product is sensitive, like foods and drugs, you should take further steps such as laboratory tests. Ensure the third-party laboratory is reliable and free of germs that could complicate the manufactured items. Items of high market value, such as jewelry, may also be subjected to laboratory tests.

Acceptance Quality Limit Inspection

Acceptance Quality Limit inspection, also known as AQL sampling, is the most common type used in checking product quality. Here, the check examples are randomly selected, with a minimum number of defects assigned to them. If the number of defects in the sample is above the maximum range, the production is considered non-tolerable and rejected. However, it does not stop there. If the flaws keep reoccurring, manufacturers examine various parameters that may have affected the production process.

The AQL technique varies between industries, depending on the product type. For instance, the medical sector will implement a stringent AQL inspection because any minor defect will expose consumers to bad health. There are usually medical standards that an AQL inspection must meet. However, stringent AQL is generally more expensive than the lesser application process techniques.

Customers play a role in determining a production company's accepted defect limit. Thus, defects can be either critical, major, or minor. A critical defect is when the product passes the defect set mark but is unsafe for usage. Another type is the major defect, which is solely based on end users' preferences. It means customers will not accept the products, leading to production waste. Then, the minor defects are usually accepted by certain customers and discarded by others. These defects will cause no harm but fail to meet the regulatory standard.

Continuous Sampling

The continuous sampling process is used for identical products with a similar production process. The result from this sampling method is usually fast and accurate. It passes each product through a testing parameter to confirm its originality. Once a check sample scores the test, it will be added to the group or batches. More so, only a portion of the check examples will be randomly selected after running them through the trial stage.

The samples also pass through the screening phase. Any sample with a defect will be tested again. However, if the number of defects is much, the testing materials and techniques must be corrected. The essence is to ensure a fast response and immediately detect any issue. Thus, it is a priority that materials or products meet the quality standard.

Factors to Consider in Choosing a Quality Inspection Company

Even though there are several inspection companies, you may have better options. You must make the best selection and avoid being caught between uncertainties. Thus, this article encourages you to consider the factors below before choosing an inspection company.

Available Services

A proficient company should offer various services with different price packages. You should also confirm if the company outsources any part of its services to a third party. However, certain critical services should be performed by the inspection company. Some of these services are; full assessment, in-production inspections, and pre-shipment inspections. You may also confirm if the company specializes in a particular quality control method above others. Nevertheless, sampling quality control is a common method, and a reputable inspection company should be able to provide such a service.

A Transparent Customer Service

The professional inspection company will make its customer relation system as transparent as possible. This will also include setting up an account manager for customers, where you will receive news on the latest updates. It also hastens the inspection process, as you can effectively communicate your preference or any intended change.

Choosing an inspection company with a trained customer service system is also an advantage. They must have professional qualifications and training that make them fit for the job. Companies like this always have customers' interests at heart, and they can handle complex projects. You may also focus on companies with the highest rating. In most cases, they have met the needs of various manufacturing companies.


You need to check if the price charged by an inspection company is worth the service being provided. In this case, you are not worried about a high or low cost. If the price from an inspection company is meager, there is a high possibility the service will be of low quality. Thus, the best way to identify the proficiency of an inspection company is to check customers' reviews. You can determine if a company consistently delivers the promised services.

You also need to go through the price list provided by the inspection company. It helps you to allocate your resources appropriately and prepare your mind on what to expect. You may also compare the price with other inspection companies until you are confident you have found your preference.

Certain factors may influence the price charged by an inspection company. For instance, if the company needs to travel to another state, the price will be higher than the average price. However, it would help if you avoid companies that charge the additional fee on the essential extra criteria. For instance, a quality inspector should ideally report on photographs, inspection, and sampling and not charge extra.

Do You Need to Improve on Quality Control?

The best way to ensure product quality is to get professionals to run the necessary tests. EU Global Inspection Company has successfully helped established companies inspect their products from manufacturing to delivery. You can be sure to get a better result as you work with experts within the industry.

EC Global Inspection Company can solve every quality control challenge and provide the most appropriate supply chain management. The aim is to make end consumers happy and help companies minimize costs. Thus, there will be no product wastage during an inspection, especially when the raw materials are monitored at the pre-manufacturing stage.

The company has over 20 years of experience working across countries, using high technology to measure product quality. Thus, the experts are familiar with diverse manufacturing sectors, including food, agriculture, health, electronics, groceries, etc. A flexible arrangement option also ensures ease while checking product quality. You may further reach out to the customer service team, which is always available 24/7.