How to Choose a Test Lab for FCC Certification of IoT Products

I’ve been an engineer in some very heavily regulated industries where products are tested out the wazoo to make sure they’re safe. Even so, getting FCC certification for an IoT product was still a significant endeavor. Choosing the right company to perform the testing is the most important decision for success with minimum expense and agony. Read on to learn about choosing a test lab for FCC certification.

What’s a test lab and why would I need one?

It was a surprise to both my boss and I that we needed an FCC compliance testing. The chief engineer had selected our IoT RF (radio frequency) module specifically because it said pre-certified. It had seemed like a safe assumption that we could go wild with sales and installation as soon as we were done manufacturing.

Imagine my shock when I found a single bolded paragraph in the User Guide. It said that, at a minimum, we needed to test any product containing this module for unintentional emissions and the product probably still needed a full certification.

Lesson learned: You should actually read any and all documentation for all components going into your system. Even if you don’t have an RF module, you may have “unintentional radiators” in your system. Check the FCC rules (listed in FCC Part 15B) to see what applies to your design. If like me, you’re starting out with little experience with the FCC rules, you should find someone who is. I started with my local IEEE Section. You can search their consultant network even if you aren’t a member.

If you need any kind of FCC certification or verification for your product, then you’ll need a test lab to do it.

Okay, how do I find a lab?

I found the test lab we used after going to an IEEE sponsored talk. (I should have gotten my membership reimbursed by work. It’s for some companies to do this, you should ask about it.) If you want to try the IEEE approach, your best bet is to reach out to the EMC Society and ask if anyone has experience, recommendations or talks you could attend. EMC testing and the EMC test lab are important things to be familiar with.

Alternatively, you can find a lab through a search at the FCC site without talking to any strangers. You should bookmark this site, even if it’s not where you start. You’ll need to check if the labs you are considering an accredited lab by the FCC testing. Many test labs do a variety of work besides just FCC verification, so every lab won’t be up to spec for the tests you need.

You can also ask your RF module vendor who certifies their products. It may save time to work with a lab that’s familiar with the specific RF characteristics of your module. If things are looking a little off, they may be able to identify the reason more quickly. We got a quote from the lab that certified the module we were using, but they weren’t a great fit for what we needed.

How do I choose which lab to use?

After your search, you may find several test labs available to you. Picking a good one will make a huge difference in how your testing goes. Here are a few questions to ask as you narrow down your equipment options.

How do I know if it’s a good company?

There’s no Yelp for hardware testing labs, so finding reviews can be tough. Ask other engineers in your area for referrals. I promise I’m not getting a commission from IEEE, but they can be so helpful here. At a good tech talk, you might get lunch, and be able to meet test lab employees and their customers. This is better than asking for testimonials from the lab since they probably can’t share specifics on their clients.

When you are researching a lab, they should be able to answer any questions you have about the process and requirements. If you aren’t sure what to ask them, you can start with these questions.

Can they do what I need?

What your device is, how it functions, and its size, all affect the testing requirements. Ask the lab about what their capacity is and if they’ve tested something similar to your product. If you will be selling your product in other countries, make sure they know what the differences in certification requirements are, and that they can perform all of the tests required.

Make sure you select a lab that has the facilities and experience to complete all the testing you’ll need for your product.

Do I need other certifications?

If you need other testing and certification done, like getting electrostatic discharge tolerance, or a CE mark (for "Conformité Européene" if you’ll be selling in Europe), find out if the same lab can do all the testing for you.

How much will it cost? What’s the lead time?

Price can vary widely. I got two quotes for the same certification on the same system that had a 25% difference in price. As far as I could tell, the only difference was that one lab was in California.

When you request a quote, be sure you also ask about lead time. Smaller labs often have really great service, but get booked up months in advance. Make sure you’ll have enough time to test and still get your product to market on schedule.

Where are they located? Can I be present for testing?

It’s great to test someplace local, where you can be on hand in case something breaks or there’s a question about how the device operates. I went to every moment of the test that I could, and I learned an insane amount. Policies vary by lab, so make sure you ask in advance.

Final questions to ask before you accept a quote

If you’re ready to get started, take a moment and get a couple final questions answered:

• Do they have a guide for the testing requirements? There should be specific guidance on the hardware setup for testing, such as power supplies and antennas. They may also need to put your system into a test mode, so be prepared to tweak the code in your microcontroller or software interface.

• Is it possible to do pre-screening? A pre-screen is a quick and dirty scan of the system emission, both powered and unpowered. It gives you a chance to see if there are unintentional radiators when a signal is transmitted from the system and if there’s unexpected emission when the system is turned on. It’s much cheaper than a full test and gives you a chance to fix any problems before you start the full certification process.

• Is there on-site mitigation help? If you do find a problem, you want to be working with someone who will help you figure it out. This is another reason that I learned so much by staying on-site during testing. From putting a ferrite bead on the board, or trying different shielding material, you want someone who knows what the options are and how they might affect the system you’re testing.

• What is the filing process? There’s a lot of paperwork involved. Make sure there’s a clear process for who fills out what, what documentation you’ll need to provide, and how the registration process is managed.

Final thoughts

With all the work that goes into a certification, you want to be sure your design is solid, and hopefully reusable in future products. A great way to do this is use PCB software, like Altium Vault^®. Altium Designer’s Design Data Management tools to keep track of versions and components within your PCB design. Good documentation is key for successful testing, and being able to use your design again.

Contact an Altium Designer representative today to learn how their tools can protect and support your designs for successful IoT product designs.