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The product approval process— testing and when required, certification— lies on the path between product design and market access. Like it or not, test laboratories and approval agencies are going to accompany you down the path from lab to market. Selecting the test laboratory you will work with is an important decision. If you are new to the process, what should you look for and what should you expect?

It is easy at first to think of the lab’s job solely in terms of the testing that you need to get done, but there is a lot more to it than that. True, you’ve got a product and you will take it to a laboratory to see if it meets the technical requirements necessary for it to be sold—that is, you are going to get it tested. For the simplest types of products, that may in fact be all there is to it, but often there is a lot more involved. The regulations and standards that a product is governed by vary widely depending on the product type.

Assessing Your Product Requirements
The approval process will have two, and sometimes three basic steps:

Testing to standards (which may include inspection and constructional analysis as well as electrical and environmental performance tests)
Report generation
Final certification and approval (where a third party does the final approval after review of the report and any additional required applications)

For simple products, the first two are so closely linked that you might not even think of them as separate steps. For example, an ITE product intended for use only in the United States and powered by safe low voltage supplies such as batteries or a separately approved and listed “wall wart” transformer will only be subject to the FCC’s Part 15 requirements, and will need no safety investigation. For such a unit, the required lab service is a simple test and report, along with instructions on proper labeling. No additional third-party review and certification is involved.

Once the product becomes a little more complex, or is more broadly marketed, the process becomes substantially more involved. If the product operates from mains power, safety becomes a concern. It must be evaluated against the appropriate safety standard (e.g., IEC 60950 for ITE, IEC 60065 for consumer electronics), and in the United States and Canada, must be approved by a nationally recognized laboratory. If the product deliberately transmits radio signals—such as a cordless telephone or a wireless LAN component – more complex testing and certification will be required. Telecom network connection brings a new round of requirements. Note that often telecom and intentional transmitter requirements will be country- or region-specific. And, if your product targets the U. S. telecom central office, be prepared for extensive electromagnetic and environmental testing to meet the operating companies’ NEBS (Network Equipment Building System) requirements. These will have to be documented in a lengthy and detailed report.

In Europe, products must meet the requirements of the EMC Directive, and usually, the LVD (Low Voltage Directive), which governs product safety. The EMC Directive introduces something new to the emissions requirements found in the United States and Canada, which are concerned with protecting communications by limiting interference—immunity. In addition to limiting interference, the Directive requires that the equipment “operate as intended” in its expected electromagnetic environment. Demonstrating this involves approximately a half-dozen additional tests, including radiated and conducted immunity, electrostatic discharge, fast and slow transients, power dips and interrupts, power-line harmonic current measurements, and mains voltage fluctuations and flicker.

This may seem daunting at first glance. It is important that the laboratory you select be able to help you by figuring out what is applicable to your product, performing the necessary tests, and helping you interface with the applicable certification bodies. Here are some laboratory features to consider:

Facilities and Equipment
Accreditations
Personnel
Reporting

Your first concern will be whether a lab can perform all or just some of the work you require. One stop shopping—having all the required work on your product performed under one roof—has its obvious attractions. Over the past 20 years, labs have tended to expand their services. It used to be that safety and EMC labs didn’t often mix; now it is very common to find laboratories offering both at the same facility. This may be done directly, or though alliances with other organizations where the laboratory acts as a test site or an agent.

Accreditations—Why are they important?
A lab’s capacity to do all a product requires involves accreditations, personnel, and equipment. The intricacies of lab accreditation alone merit an article in themselves, but the basics are easy enough to understand.

Many laboratories will claim accreditation to IEC Standard 17025, “General requirements for the competence of testing and calibration laboratories” for a number of different standards. What does this mean? It means that the laboratory has undergone a standards-specific competence assessment by a nationally recognized impartial third party, such as, in the United States, A2LA or NVLAP. Sometimes this merely provides a certain amount of reassurance; often it is essential.

Here are two examples where accreditation is a must. First, for equipment claiming compliance to the FCC’s rules under a Declaration of Conformity, the measurements must be carried out by a laboratory which is accredited to ISO/IEC 17025 (FCC §2.948(d)). Second, where international approvals are required, as is often the case with telecom or intentional radiators, accreditation of the test laboratory is effectively mandatory. When two countries have a memorandum of understanding concerning accreditation, the international accreditation bodies will recognize data from a lab accredited by their corresponding accreditor. The agreement runs between the accrediting bodies. For example, A2LA (a U.S. accreditor) has an agreement with NARTA in Australia. This facilitates the acceptance of telecom test data from an accredited US lab by the Australian telecommunications authorities.

A second form of accreditation is to ISO Guide 65, “General requirements for bodies operating product certification systems.” In working with electronic products in the United States, you will commonly encounter two types of ISO Guide 65 certified facilities: Telecommunication Certification Bodies(TCBs) and safety organizations (Nationally Recognized Testing Laboratories, or NRTLS for domestic safety, as well as members of the internationally based CB-scheme). This too is an accreditation, although the scope is different than the measurement facility evaluation of ISO/IEC 17025 – operation of a certification scheme – as are the accrediting authorities. For example, in the United States, the TCBs are accredited under the auspices of ANSI to do FCC certification for devices requiring that form of authorization, while NRTLs are accredited by OSHA, the Occupational Safety and Health Administration.

Other, more specialized recognitions lie outside of the formal ISO/IEC 17025 and ISO Guide 65 scheme. For example, in the world of NEBS, Verizon imposes its own scheme of accreditation through its Independent Test Laboratory (ITL) program to assure itself of the validity of NEBS data.

The details of what accreditations and scope a laboratory should have to meet your needs may be straightforward or complicated. As noted above, it is not essential to have everything in-house if the laboratory has alliances and working relationships with other organizations.

Equipment and Facilities
Labs can vary widely in the way they implement their test facilities, especially in the area of electromagnetic compatibility. Some of these variations are the result of operational philosophy, as in the degree of automation employed, while others are more physical:

Emissions test sites—open area or anechoic
Available power, type and quantity (available voltages, phases, and power capability)
Equipment handling: Loading facilities, maximum size and weight limitations
Degree of support equipment, fixturing, and cabling pre-built and in place
Variety of standards supported

If you have multi-rack systems, you need to work with laboratories that can ship and receive them properly, not to mention having large enough test sites equipped with heavy duty mechanized turntables. On the other hand, if your equipment is modest in size, a simple manual turntable will be adequate and in fact easier to use.

For large systems, or systems running from unusual power combinations of phasing, frequency and voltage, you should inquire as to the laboratory’s power facilities. Almost anything can be powered with rented generators, but this will involve extra cost.

Personnel and Communications
A key issue in working with a laboratory is service. Three aspects of service you should consider are the amount of technical expertise available, the responsiveness of the lab’s personnel, and its IT interface to the client.

If all goes well, the lab will test, report, and, if it is required for your product, certify. What if the unit fails to meet the test requirements? Some labs will provide on-site consulting, or have referral arrangements with consultants who can help. This may be of value to you. You may also wish some pre-test review, possibly early in the design process, of the equipment to spot potential problem areas. Whether the laboratory you work with provides this, you provide it in-house, or you contract for it separately, is up to you. It is a good idea, however, to plan in advance where you will look for help if you require it. Bear in mind that diagnostic testing may involve additional charges which are not fully predictable. Sometimes product modifications are minor and can easily be incorporated; on occasion this is not the case, and retesting will be necessary after the modifications are introduced into your unit.

Communication with the sales and lab staff is important. Up front, you want to have confidence that you and the lab have correctly assessed your product’s compliance needs for the markets you are targeting. Once the project starts, you want progress reports on scheduling, test results, and the progress of your reports. Accuracy and predictability are what you need in order to meet your schedules.

A client interface to the lab’s IT system can make life easier. Some laboratories offer an electronic updating service where schedules, test results, and reports can be easily found.

Working with the Lab
Once you’ve selected a laboratory to work with, you are beginning a professional relationship where vendee (that’s you, the client) and vendor (the lab) have complementary goals. You both want a mutually beneficial relationship. The client wants efficient service; and the laboratory wants to provide it in order to please the client and cement the relationship. This requires work on both sides.

In order for the laboratory to perform efficiently, it needs product support and documentation support from the client. Testing requires an adequately supported product in terms of hardware and software. It isn’t sufficient to just drop off the equipment at the lab door; it has to be properly configured. Many tests require that the product be operational. For emissions tests, it is usually necessary to have realistic software and hardware in place so that worst-case emissions may be measured. The software doesn’t have to be a full production release, but it has to exercise all significant functionality of the equipment under test.

Immunity tests require that the product maintain its function and perform within specified limits. On a communications product, where performance might be specified in terms of bit error rate, external communications test equipment, specialized cabling, and detailed operational instructions might be in order. Modified firmware or software may be necessary to enable certain functions for some telecom tests.

If your product uses a few standard cables, shielded or unshielded, your laboratory can probably supply them. But, if your product uses cabling that are unusual or proprietary, you’ll have to supply them. Also, if your product uses large numbers of cables—as is common with some types of telecom gear, you may have to provide them.

Advance preparation prevents unnecessary delays and helps testing stay on schedule. Your laboratory should be able to help you prepare. Sometimes the information on what will be needed is provided verbally by the sales department; in other cases a hard copy document will be provided.

For some types of equipment, documentation support will be necessary. The technical support we’ve been spoken of in preceding paragraphs is aimed at getting the equipment to function during testing. However, for some types of approvals, manufacturer-supplied documentation will need to be incorporated into the final laboratory report along with test data. For example, product safety evaluations require information on the properties of safety critical components and selected schematics. Some standards, such as IEC 60601-1 (medical equipment) and IEC 61010-1 (control and instrumentation equipment) require the instruction manual, or key excerpts of it in such areas as:

Protective symbols and their interpretation
Operator access to mechanically or electrically dangerous areas of the equipment
Cleaning, disinfection and sterilization (medical)
Protective earthing practices
Warnings about hazardous gases
Battery Replacement
Use of accessories

The certification report and application cannot be finalized until all required documents are provided.

How long will it take?
We’ve implied that the approval experience can vary from quick and painless to involved and long-term, depending on the product and type of approval sought. Also, we’ve noted that the technical and documentation support required will vary considerably depending on what type of product you have.

In Table 1, we’ve given rough descriptions of the process and the level of technical and documentation support required for several common types of equipment approvals. We’ve focused on the work at the laboratory, including testing and report preparation. Note that when a third party is involved in certification, an additional and variable waiting period will be involved while your report and application are reviewed.

A key part to a successful compliance experience is preparation. If you can support the laboratory so it can work at maximum efficiency, the process will flow smoothly and according to your expectations. n

Type of Approval	Process Notes	Technical Product Support	Documentation
EMI – unintentional radiator	Short. Emissions test and report. Troubleshoot as needed.	Minimal to modest. Product must function, be adequately cabled, have needed peripherals	Minimal. For FCC, some instructions to user on interference.
EMI – intentional radiator	Short to moderate. More detailed standards, often formal report to TCB (US) or to foreign radio authority.	Modest. Depending on type of transmitter, special data configuration, or forcing of operating mode may be necessary.	Minimal to modest.
EMC – Immunity	Primarily driven by EU EMC Directive. Tests in multiple areas. Report straight forward	Moderate operational support. Cabling, peripherals, software to verify performance meets manufacturers specifications under test application.	Minimal. May need schematics to aid if diagnostics and modifications are required.
Telecom	Test; formal report to third party approval agency. Length of test depends on type of equipment (e.g., many modes in newer XDSL units; multiple interface types lengthen test)	Moderate, and product dependent. Since equipment must operate in lab test bed, customization of test software may be necessary.	Modest. Interface schematics. In US and Canada, particular regulatory language must be inserted.
Product Safety	Construction/Design investigation, followed by testing and detailed report. Subsequent review (may be by same or different organization) and listing	Modest on operational side. May need manufacturing support to find info on construction materials such as plastics.	Fairly high. Partial schematics, parts lists, manuals. Critical component approvals and conditions of use important.
Bellcore (GR-1089, GR-63, and Electro-optical FOC)	Long series of tests, followed by very detailed formal report. For environmental (GR-63) videos of destructive tests (fire, earthquake) are included in report. For FOC (passive fiber optic components) environmental and reliability tests take months.	High. Multiple tests require frequent setup/breakdown. Specialized data testsets, customized software often needed to demonstrate levels of performance. Multiple product samples needed for GR-63 and for optical FOC tests. Engineering support needed in case of test failures.	Moderate to high. Important to fully document system tested (plug-ins, serial numbers, firmware/software revision levels). For reliability based GR- standards, manufacturer has to supply manufacturing and quality information.