Quality control (QC) is a core component of success in the manufacturing and export-import business. In the past few years, consumer markets have been rocked by several large scale quality issues. From confectionery to pet food, motor vehicles, and even medical products, behind each case, there is evidence of disregard of quality control best practices leading to losses in the billions. But, the most disheartening consequence is the millions of consumers affected by the events. Most quality issues are avoidable. You need to exploit quality control services.
How can Tetra Inspection help you?
Quality Control Inspections Services
What is the Product Inspection?
Product inspections are used by quality control inspectors to assess whether the product conforms to AQL level, design requirements, and specifications. Quality control inspectors conduct product inspections at any stage of the production process to highlight the quality and regulatory issues early. This provides you ample time to take corrective measures if products do not conform to quality requirements. Product inspection is a part of on-site quality control inspections services.
On-site Quality Control Inspections Services
On-site quality inspection services require inspectors to visit the producer’s factory at any stage during manufacturing to monitor the process based on the requirement of the supplier or buyer. Inspectors focus on the client’s requirements. There are five types of on-site quality control inspections:
Inspection services are conducted as a quality control chain where the inspector undertakes one product inspection or quality check at a time. To avoid mix-up, your quality control inspector will a comprehensive quality control checklists.

What is Quality Control?

Who is a Quality Control Inspector?
Quality control inspectors are third-party inspection companies like Tetra Inspection with years of experience, expertise, and resources to conduct product inspections and quality checks according to international standards. The most established QC inspectors offer a wide range of quality control services, from audits to on-site inspections and checks. Manufacturers, retailers, and export-import companies can outsource all checks and product inspections in their quality control chain to a reliable QC inspector.
Why Should You Hire Quality Control Inspectors?
Hiring quality control inspectors can help you avoid quality issues in the future. You will also have peace of mind knowing that your inspections and tests are in capable hands.
Experienced quality control inspectors like Tetra Inspection can streamline factors that contribute to product quality. Quality control in manufacturing relies heavily on the expertise of QC inspectors. Here are a few reasons why you need to hire a quality control inspectors:
Whether you manufacture, export, or import, you need quality control services offered by reliable and experienced QC inspectors.

What is a Quality Control Checklist?
Initial production checks start before production begins and focus on clarifying the requirements and specifications to ensure the manufacturer can deliver the quality needed. Inspectors can also assess the manufacturer’s process, expertise, and materials. The checks can last until 20% of production has been completed to allow inspection of the first items to be manufactured. This step is known as First Article Inspection and can highlight defects to be corrected before the start of mass production.
Also known, On-Line Inspections, During Production Inspection (DUPRO), is an on-site quality inspection service conducted in the early stages of production when about 20% of the batch has been produced. It can highlight any defects early for correction.
Pre-Shipment Inspection (PSI) involves a systematic inspection of a sample selected randomly from all the batches already produced. It is conducted based on ISO standard sampling procedures to ensure the accuracy of the results. PSI is carried out near the end of production when at least 80% of the units in the whole order have been produced.
Container loading check focuses on ensuring that all the batches are packed correctly for shipping. Inspector checks the total quantity and for different sizes, colors, and styles in shipments. They also ensure the safety of the products during shipment using packing materials like Styrofoam.
Production monitoring is conducted on-site to inspect factory processes and implementation of specifications. PM can enhance accountability and professional working relationship.
Pre-Customs Clearance Inspection is carried out before the dispatch of shipments. It includes the visual checking of packages, quantity, commercial invoices, and so on.
A quality control (QC) checklist, also known as the inspection checklist, is a criteria sheet to clarify product requirements. Five key elements should be outlined extensively and clearly in your quality control checklist:
- Product requirements: To avoid confusion, product requirements should specify materials to be used, and specifications like weight and dimensions. You can include a sample with the color for comparison. For electronics, including labeling and markings like CE mark.
- Packaging requirements: An effective quality control checklist clarifies how the products should be packaged, including weight, dimensions, and labeling requirements like size, contents, and markings. Labeling is particularly important if the cartons convey your brand.
-
On-site quality checks and tests:To avoid non-compliance and quality issues, you should list the tests and inspections, outline tolerances, and specify pass/fail criteria.
- Defect classification: It is used to determine whether the product passes or fails the inspections. Defects under AQL standard are classified into three types – minor defects, major defects, and critical defects that should not be tolerated.
- Constructive collaboration between all parties in a quality control chain is vital for success. You have to outline how all parties will collaborate during the inspection and start by consulting your supplier and QC staff as you develop your QC checklist.
- The other types of quality control services include QC checks, QC audits, and quality assurance.

Quality Control Testings
Quality control checks are conducted both on-site and off-site to determine whether the product meets the Acceptable regulatory requirements, or satisfies the client’s product specifications. QC inspectors conduct initial production checks and container loading checks as part of on-site quality checks during product inspections. Quality control checks also include on-site and off-site lab tests.
On-site quality control lab tests
This type of quality check is usually conducted during product inspections. Most quality issues tested on-site are common or known issues and undertaken in the factory’s labs or test areas. On-site lab tests can highlight the raw materials used on your product. QC inspectors can test for hazardous chemicals to ensure your product does not violate regulations or pose safety risks.
Off-site quality control lab tests
Off-site quality checks involve highly advanced lab tests in controlled environments. A sample is collected and sent to a well-established lab for advanced testing like functionalities, usability, and safety. If the contract specifies the delivery of lead-free products, the inspector can take a sample to test for lead in a lab. Off-site lab tests are useful in quality control checks and ensure your products conform to safety regulations.
Quality Control Audits
Quality control audits are conducted when importers and retailers are searching for the right partner to supply the products they need. It mainly focuses on evaluating if a potential supplier can deliver the client’s requirements. Most experienced quality control inspectors like Tetra Inspection offer Manufacturing Audits and Ethical Audits as part of quality control services, which include:
- Verification Audit: This is conducted to verify the authenticity of a potential supplier.
- Social Audit: QC inspectors use this audit to assess the ethicality of supplier’s social practices.
- Factory Audit: It assesses the capability and capacity of the potential supplier to deliver.
- Environmental Audit. Quality control inspectors evaluate if the supplier’s operations degrade or pollute the environment.
- Specific Audits. These are unique audits for specific importers, and sellers like Amazon FBA used to evaluate whether a company qualifies to supply products to Amazon sellers.
Quality control audits should be conducted by profession according to international standards. These audits can protect your brand against ethical and operational risks and also ensure safe working conditions in your supply chain. The profile of potential suppliers can help you choose the right supplier for your business.
Quality Assurance Services
Quality Assurance Services By Tetra Inspection
Tetra Inspection offers a wide range of quality control services with years of experience in the field. Our quality control services include Factory and Ethical Audits and inspection services at every stage of manufacturing.