Certification marks can be used in different ways on many types of products. Specific marks and their types will vary depending on the region and the certification body. At Intertek, for example, products can be listed, recognized, classified, have a limited production certification (LPC), or be field evaluated and certified.
Because it is extremely likely that inspectors and authorities having jurisdiction (AHJs), manufacturers, and users may encounter a variety of marks in their daily lives, it is important to understand the differences between the certification options. To do that, it is important to know what is meant by the various certification types, and how they differ from each other.
When a product or component is listed, samples have been evaluated and found to be compliant to the product safety standards that apply to that product. Listing illustrates full compliance to required standards. It allows a manufacturer to continuously label production of the item, provided they do not deviate from the tested prototype in subsequent production. To ensure this, listing requires quarterly follow-up inspections and follow-up service reports. Given these requirements, listing is a good option for volume production. Testing can occur at a third-party testing lab or in the factory. Certification is based on a review of the testing data and granted by the certification body. A listed mark is accepted nationwide.
Recognized components are parts or objects that meet certain specifications and are used in an end-product. One example is a fuse used within a power supply. A motor casing is another. Recognition illustrates that components of a larger product meet certain specifications. It includes information on how the component was assessed and how it can be used to ensure the end-product complies with necessary safety standards and requirements. Using recognized components in an assembly or larger product can help with the inspection or certification of the end-product since those recognized components do not need to be reassessed.
Like the listing options, recognition allows manufacturers to continuously label production, requires quarterly follow-up inspections, and follow-up service reports. Testing can occur at a lab or factory. Recognized component certification is good for volume production and has nationwide acceptance.
A classified product or component has been assessed to accepted standards; however, only certain aspects of the design (for example, electrical safety) have been assessed, while others (such as physical characteristics or treatment effectiveness) are not evaluated. A classified medical product, for example, may meet the safety requirements of medical product standards, but not requirements for electromagnetic compatibility (EMC).
Classification should include the standard to which the product has been evaluated and represent evaluation to the full requirements of the stated standards for safety. This option requires quarterly follow-up inspections, as well as follow-up service reports. It is a good option for volume production as it allows manufacturers to continuously label production. Testing can occur at a testing lab or factory.
Limited Production Certification (LPC)
Limited Production Certification (LPC) applies when a limited number of pieces of equipment, possibly even just one piece, are manufactured or produced. Some certification bodies refer to it as single batch certification. An LPC involves illustrating full compliance to recognized standards by assessing a representative sample in the lab or factory. The process also includes a review of components, markings, and associated drawings. An LPC report is issued at the end of the process.
Following the assessment, equipment is certified, and the applicable label will be attached at the final point of assembly. Certification applies to a limited number of units, produced over a defined time. Once certified, the product can be sold anywhere in the United States and Canada. Because it is for a set number of units in a certain timeframe, ongoing quarterly inspections are not required.
There are several situations that may call for an LPC. If a limited “market test” run of a product that would normally be mass-produced is planned, an LPC can be valuable for the production schedule. Likewise, if a signification modification to a listed product will be made to a certain number of units, LPC may be used where a published or draft standard exists.
A “Field Evaluated” mark means the equipment was assessed and certified onsite via a field evaluation, a non-destructive compliance assessment of equipment that is either unlabeled or has been “red tagged” by an AHJ.
Field evaluations can also be used for one-of-a-kind, custom equipment or prototype equipment not intended to be mass produced.
During the field evaluation, an expert goes onsite to assess the equipment for safety risks, markings, warnings, and features, as well as doing a construction review and some non-destructive tests. If a product complies with applicable requirements, the unit is labeled with the field evaluation mark and a detailed report is issued. Non-compliant products receive a non-compliance report and can be corrected for further evaluation and potential certification.
With a variety of products serving a variety of uses, it is important to understand the difference between the certification types. This understanding can aid in equipment manufacture, inspections, and completion of projects. This in turn helps to ensure success for all involved.