Could Your Product be Exempt from EMC Testing Altogether?

Andy Eadie EMC Exemptions, Regulations Tips 44 Comments

This week I’m going to talk about a few little known exemptions that I learned about when I was wading knee deep through the murky waters of several regulatory standards. I hope you can take advantage of a few of them and save yourself and your company some serious money. Firstly, I’ll focus on exemptions related to the EMC Directive for CE Mark testing. Then I’ll go into the top 10 exemptions to part 15 of the FCC’s rules! Please let me know your thoughts in the comments section at the bottom.

CE Mark Exemptions

CE Mark testing under the EMC Directive is usually quite a bit more expensive than FCC testing because it involves emissions and immunity testing whereas FCC testing usually only involves emissions testing. Therefore, if you can avoid it you stand to save some serious time and money.

The latest guide for the EMC Directive outlines many products that are exempt. Firstly, take a look at this flow chart that gives you a general overview of the applicability of the EMC Directive. CE_Exemptions If you’re reading this blog post, the chances are that you are involved with the design of some kind of electronic or electrical equipment, so it’s safe to skip the exemption at the top of the tree.

Next is the ‘excluded product families’ exemption. This refers to equipment covered by other standards such as radio equipment (covered by the R&TTE Directive instead). This doesn’t necessarily mean that EMC testing won’t be required for your product; it is usually just defined differently in another standard.

Components, sub-assemblies or other units which are intended for incorporation into apparatus, but which have no “direct function” for the end user, are not considered to be apparatus for the purposes of the EMC Directive. This is a good one to take advantage of if your company makes electrical products that will be integrated into other equipment. Note that your end customer may demand proof of compliance even if it isn’t mandatory.

Some examples of this are:

– Components forming parts of electrical circuits, e.g. resistors, capacitors, coils, transformers, diodes, transistors.

– Cards or modules required for the minimum level of function of the apparatus, e.g. central processing, minimum memory.

– Internal power supplies, including batteries- cathode ray tubes, light-emitting diodes (LED’s), liquid crystal displays (LCD’s).

– Private telecommunications and data networks

9 kHz Lower Limit

Measuring emissions from electrical equipment in Europe is only required for equipment that has internal switching above 9 kHz. This may be especially useful knowledge if you are designing a low frequency product such as a simple micro-controller or a low frequency switching power supply. If you have the flexibility to drop the highest clock frequency in your product below 9 kHz, then do so because you’ll avoid emissions testing altogether and save yourself a headache!

Low Voltage Directive (LVD) Exemptions

Closely related to the EMC Directive for CE Mark compliance is the LVD which covers electrical safety requirements. For many electronic/electrical products destined for sale in Europe, the recipe for demonstrating compliance with the rules is:

CE Mark  = EMC + Safety (The LVD)

And the LVD applies to: “all electrical equipment designed for use with a voltage rating of between 50 and 1000 V for alternating current and between 75 and 1500 V for direct current. Voltage ratings refer to the voltage of the electrical input or output, not to voltages that may appear inside the equipment.

I’m not particularly familiar with safety requirements, but there is a well known method that a company can use to avoid this arduous testing requirement. Typically safety testing costs $5000+ per product, plus an annual ‘maintenance’ fee. It’s obvious why companies seek to avoid the fees if possible and if safe to do so.

Based on the scope clause above, you can see that if you reduce the input voltage to your product below 50V AC or 75V DC, then the directive does not apply. If your design constraints allow, rather than having a mains AC input into your product, all you need to do to avoid the LVD is purchase a pre-approved (CE Marked) AC-DC power adapter and ship it with your product.

Make sure that you trust the power adapter vendor, because often cheap power supplies will bear the CE Mark, but not actually be compliant. This can bite you in the butt because a non-compliant power adapter can cause your whole product to fail a number of tests such as conducted emissions, surge and EFT. I’ve also witnessed cheap power adapters that were ‘cost reduced’ after initial passing samples were provided, which lead to a conducted emissions failure!

It’s key here to note that even if your device is exempt from the LVD, there may caveats or other safety standards that apply to your product. Always double check with a test lab, but also read between the lines of their ‘sales speak’ to work out what is mandatory and what are just scare tactics.

Top 10 FCC Exemptions

Most electronic devices destined for sale in the US fall under Part 15 (CFR 47) of the rules for limits to the unintentional (and sometimes intentional) emission of radiation. There are a number of exemptions that you may be able to take advantage of that you should keep in mind when designing your products. You can find the bulk of this info in section 15.103 of the rules. The FCC  recommends that you still aim to comply with the rules, and they have the power to halt sales of your device if the device has been found to cause harmful interference, so use with caution! FCC testing exemptions

1. A digital device utilized exclusively in any transportation vehicle including motor vehicles and aircraft. (Note: wireless devices are subject to other FCC rules)

2. A digital device used exclusively as an electronic control or power system utilized by a public utility or in an industrial plant. The term public utility includes equipment only to the extent that it is in a dedicated building or large room owned or leased by the utility and does not extend to equipment installed in a subscriber’s facility.

3. A digital device used exclusively as industrial, commercial, or medical test equipment.

4. A digital device utilized exclusively in an appliance, e.g., microwave oven, dishwasher, clothes dryer, air conditioner (central or window), etc.

5. Specialized medical digital devices (generally used at the direction of or under the supervision of a licensed health care practitioner) whether used in a patient’s home or a health care facility. Non-specialized medical devices, i.e., devices marketed through retail channels for use by the general public, are not exempted. This exemption also does not apply to digital devices used for record keeping or any purpose not directly connected with medical treatment. (Other EMC rules usually apply instead)

6. Digital devices that have a power consumption not exceeding 6 nW.

7. Joystick controllers or similar devices, such as a mouse, used with digital devices but which contain only non-digital circuitry or a simple circuit to convert the signal to the format required (e.g., an integrated circuit for analog to digital conversion) are viewed as passive add-on devices, not themselves directly subject to the technical standards or the equipment authorization requirements.

8. Digital devices in which both the highest frequency generated and the highest frequency used are less than 1.705 MHz and which do not operate from the AC power lines or contain provisions for operation while connected to the AC power lines. Digital devices that include, or make provision for the use of, battery eliminators, AC adaptors or battery chargers which permit operation while charging or that connect to the AC power lines indirectly, obtaining their power through another device which is connected to the AC power lines, do not fall under this exemption.

9. Same as the low frequency exemption for CE, if your device doesn’t generate and use timing signals or pulses at a rate in excess of 9,000 pulses (cycles) per second (9 kHz), then you can avoid emissions testing altogether.

10 Home-built devices: Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use. It is recognized that the individual builder of home-built equipment may not possess the means to perform the measurements for determining compliance with the regulations. In this case, the builder is expected to employ good engineering practices to meet the specified technical standards to the greatest extent practicable.

Caveat: Responsible parties should note that equipment containing more than one device are not exempt from the technical standards in this part unless all of the devices in the equipment meet the criteria for exemption. If only one of the included devices qualifies for exemption, the remainder of the equipment must comply with any applicable regulations. If a device performs more than one function and all of those functions do not meet the criteria for exemption, the device does not qualify for inclusion under the exemptions. (Note: for example, if you have a device with a wireless transmitter and some baseband circuitry that happens to be exempt, the wireless transmitter still has to be tested).

Wrap Up

So that was an outline of a few exemptions that I hope you can take advantage of at some point in your career. Please confirm with your test lab whether you are indeed exempt as there are some caveats to this information. If you can’t take advantage of any exemptions, you may want to have a look at how to source test equipment bargains for doing some pre-compliance testing.

Have you ever successfully used exemptions? What has your experience been with your test lab giving you guidance on what tests you can avoid? Or any other comments/suggestions in the comments section below! In a future post I’ll delve into some lesser known ways to avoid testing, such as risk assessments (for CE), in-house testing substitutions and ways to minimize re-testing of products in a family with minor hardware differences.

Andy Eadie

Andy Eadie

Andy Eadie is a former senior hardware design engineer and former EMC test lab owner. He's had a weird fascination with magnets since 4 years old and has been publishing articles, eBooks and online courses since he founded EMC FastPass in 2014.
Andy Eadie

Comments 44

  1. I believe that power supplies that produce signifigant energy levels are covered by IEC safety standards ( and the LVD ) regardless of the voltage produced. These standard not only address voltage levels, but also heat rise and fire safety. High currents can cause fires regardless of voltage. Its not a ggod iea to assume your are excempt form safety standards because of low operating voltages only. There are also product specific safety specs that address low voltage power sources like DC/DC converters.

    1. Hi Steve, thanks for the input. I couldn’t find any reference in the ‘Guidelines on the application of the the LVD” (http://ec.europa.eu/enterprise/sectors/electrical/files/lvdgen_en.pdf) that includes higher power equipment not otherwise excluded by the scope mentioned in the article. Could it be that the equipment you have in mind is subject to safety standards other than the LVD?

      I absolutely agree that you should verify the applicability of other safety and EMC standards to your product. This article only outlines some potential exemptions to the specific standards mentioned. when in doubt, ask your test lab!

  2. Hi Andy
    I work for a UKAS accredited UK test lab. Our interpretation of the LVD is that if you supply a product that is powered from the mains, the whole product is within the scope of the LVD, irrespective of whether it consists of a separate power adaptor or not. Having a separate adaptor that is already certified simplifies the testing and reduces the cost, but does not remove the requirement for fully assessing the product.
    Steve Boegle is correct that Safety requirements still apply for equipment below the LVD limits, but this is not invoked by the LVD. For consumer equipment the GPSD would apply, or for radio equipment the R&TTE Directive applies. Neither of these have lower voltage limits. Often the same Standards as listed for the LVD can be used to confirm compliance of excluded equipment.

    1. Hello Ted,
      You state that “the whole product is within the scope of the LVD, irrespective of whether it consists of a separate power adaptor or not.” Could you please direct me to a regulatory or a guidance document in support of this statement? From what I have been able to find so far is the LVD directive which refers to the “equipment rating” (which is of course different from the external power supply rating) and the LVD guidance document which only mentions integrated Power supplies being in the scope of the LVD directive. Thanks.

  3. Can you clarify the exemption statement 3:

    A digital device used exclusively as industrial, commercial, or medical test equipment.

    I ask, as one can interpret this as meaning:

    a. industrial, commercial, or medical test…. equipment
    meaning – Industrial equipment, commercial equipment, or medical test equipment

    b. industrial, commercial, or medical …test equipment
    meaning – Industrial test equipment, commercial test equipment, or medical test equipment

    Which is it, as there is some ambiguity with the statement.

    Thank you in advance!

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      Author
    2. The meaning of this sentence is your item b

      Industrial test equipment, commercial test equipment, or medical test equipment.

      “Test” equipment is the key word. Otherwise, the definition of Class A would make no sense.

  4. Are there any exemptions for “small run” items (powered off of mains)? It seems that there isn’t a proper exemption for someone who say, designed a unique device for a small market but never expects to profit more than $5k off of building a small run of devices (say 100 or so). Where do the small time guys fit in this picture?

    1. Good day N. Gladstone,

      I believe the standard allows for a limited number of prototypes only…5 if I remember… and I believe that they cannot be sold and must be suitably labelled… i.e. for testing only.
      To my knowledge there is not exclusion for small firms and/or limited production runs. In reality small volumes would be off their radar and would only be officially an issue if the device caused excessive interference resulting in complaints. However, if one exports the items then most countries require some form of conformity declaration which could get you in hot water should you fraudulently completed it.

  5. Can you comment on host devices containing an MCU, storage devices such as a SSD, ethernet switching, etc. that support otherwise certified RF modules (ISM, wifi and cellular)? It is my understanding that such devices REQUIRE registered testing lab certification, but I have a client that is under the impression that those host devices can be self-certified.

    1. Depends where you’re selling into. The US, Canada, Australia, Japan etc would all require testing at a listed or accredited test lab. Europe is a little more ambiguous, but a long story short, yes you would also need to have it tested at a 3rd party lab. If you were trying to do it yourself legally, somehow you would need to prove compliance with the rules, so you would essentially need to have a full lab yourself.

      1. Andy,

        Thanks for the reply. My client now understands the necessity of full testing and is proceeding forthwith. They were unaware of the issue (their expertise lies elsewhere) and expressed their appreciation for my bringing it to their attention.

        Your response confirms my viewpoint on this important matter. The costs associated with the launch and shipping of a non-compliant product would have been staggering.

        Again, thanks!

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        Author
  6. “10 Home-built devices: Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use.”

    So kits would still need FCC certification?

  7. So, a 6V/9V/12V battery operated device would not need certification? The batteries will not be charged while inside the device, nor will it be AC powered – no power adapter. There will be no Bluetooth or other wireless control.

    Thanks.

  8. I want to understand about conducted immunity test exemption.
    Is it possible exempt conducted immunity test if my device is battery operated industrial measurement device with USB micro AB connector port used for charging and same port is used for PC/Laptop Communication?
    I want to go for CE certification. I am using CE certified USB power adapter charging and All function of device works only with USB commands through laptop, and device never uses AC power for its functionality.
    Please help me.

  9. Is my understanding correct that a heating appliance that has a random phase control switching at only 120Hz and drawing 16Amps is exempt?

  10. Regarding the FCC exemptions (specifically #10): What about if I were to have “home built” devices that I will not be selling or marketing in any way, but will be given away to research partners for Beta testing the device? This would be a quantity greater than 5 devices.

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      Author
  11. Hi Andy,
    I have seen several devices sold, even in Walmart (US)
    with only CE marking. Is this allowed and can I use this
    in my product instead of FCC/UL marked product.
    Thx

  12. We have been designing and manufacturing optical polishing and related equipment since the early ’80’s. We received CE certification in the late ’90’s.
    We are considering a position sensor that has a 5 volt potential that when contact is made, an arm stops moving. This will be in the vicinity of the operator’s hands in a wet environment. Assuming that we can make this work, will this device pass CE?

    Thank you.

  13. Hi,

    I’m designing a very small wearable medical device operating with less than 4mA average current, and using BLE. The transmission protocol requires two crystals at 32kHz and 4MHZ. This is only to be used under the supervision of a medical professional (although at patient’s home). Do I need to do EMC testing? My feeling is that because of the low currents/dimensions of the circuit, there is no way the emissions are going to be high enough not to pass the standards, but if I wonder whether there is an easy way of justifying this without having to do testing

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      Author

      Yes, you more than likely still need EMC testing, and possibly RF depending on whether you’re using a pre-certified module. Medical device EMC is usually covered under EN60601-1-2. Medical device compliance can be extremely in-depth and challenging – I would recommend seeking consultation from an experienced company to assist you with this process.

  14. Thank you Andy. May I ask: since standards are not compulsory, ie. compliance can be proven with a different type of evidence, there are million of Bluetooth systems out there that cause no interference (because of the characteristics of the protocol and the emitted power), and Bluetooth Low Energy is at least one order of magnitude lower in power that Bluetooth, why would emission testing be required? (BTW, physics modeling can also prove that the rest of the components added to the transmitter can not cause problems either because of the values of the currents and the very small sizes of the PCB).

    I understand the EMI would still need to be tested.

    1. Post
      Author

      Even BLE can produce emissions over limits pretty easily. Testing ensures that the designer complies with the RF rules in the region that the product is being sold into. It isn’t just noise levels, it’s channel allocation, band edge compliance, dwell time and many other factors. Only sometimes can compliance be proven with different types of evidence (such as CE Marking (not in every case)).

      For any other applicability questions, please direct to an accredited lab.

  15. Hi Andy,

    May I please check for a battery operated Bluetooth headset (chargeable with USB charging cable) and it can also take in audio from a 3.5mm audio cable, is it required to test the EN61000-4-4 EFT test in order to qualify for the CE marking or can this test be exempted?

    Thank you.

  16. Hi Andy,

    I want to get a CE Marking for an ECG Device which is operated by a 5V lithium ion battery. It consists of a bluetooth and wifi modules as part of the ecg board. I would like to know if emission and immunity tests are applicable. Thanks in advance.

    1. Yes I believe emissions and immunity testing would be applicable if you’re going the harmonized standards route to proving compliance with the essential requirements. I believe the applicable standard would be EN301489 (available for free from ETSI.org). Always check with an accredited lab.

  17. Hi,
    My product is speed switch trasnmitter to be used in oil and gas industry for measurment and control of speed of turbine and engines. It uses the 24V DC for power. Will surge and conducted emisiion tests are applicable on it?
    Also my product is required CE marking for selling in the US market.

  18. Dear Andy,

    I have just bought your “Global Certifications For Makers and Hardware Startups”. Good job !
    I have seen the exception 9 (about 9 kHz) of the “Top 10 FCC Exemptions” is not the same as in you Website.
    My question is : I have to integrate a microcontroller into an existing device (fully analog active speaker, AC powered) to supervise the power supply, and I would like if I have to stay under 9 kHz to keep the CE certification.
    Many thanks in advance for your help.

    Best regards,
    Ralph

    1. Post
      Author

      #1.. there isn’t any such thing as ‘CE certification’. It’s a manufacturer’s declaration.

      #2.. Check out the CE Mark Guide page 53 (http://ec.europa.eu/DocsRoom/documents/9863/attachments/1/translations/en/renditions/pdf).

      “Although the EMC Directive does not specify a frequency range, it is
      general practice to take account of the range of frequency encompassed in
      the EMC assessment from 0 Hz to 400 GHz. This does not mean there is a
      need to apply a full assessment within this range as certain phenomena are
      limited in frequency range (e.g. for conducted high frequency emission:
      the frequency range to take into account is usually 9 kHz to 30 MHz). For
      some apparatus, electromagnetic phenomena are inherently limited in
      frequency range by the principle of construction or the physical nature of
      the apparatus.

      The frequency range to be applied in the assessment depends on the nature
      of the apparatus and its intended use. However it is important to make sure
      that the relevant frequency range has been covered in combination with the
      phenomena to be assessed.”

  19. Hello Andy,
    Thanks for these valuable comments on a very complicated and grey legal/political/technical environment.
    As an importer/distributor and maybe manufacturer life has not been made easier although this was one of the major concerns of the EC setting up the directives….

    I am referring to your exemption case involving a box with an internal switched power supply, fed for instance by an external 24V CE (EMC and Safety and RoHS and Ecodesign and Energy Class Labelling) compliant adapter (so we’re in the SELV application domain for the box here). Additionally assuming there is NO OTHER equipment in that box that generates additional issues about EMC except for some basic wiring between the power converter and say an LED..
    My conclusion is that one can thus safely assume that CE EMC compliance/certification of the internal switched power supply makes the whole unit exempt of EMC compliance testing? Is this a valid assumption?
    Needless to say that Safety, RoHS and Ecodesign of the unit remain to be assessed before CE can be labelled and DOC can be made.

  20. Sorry to dredge up an old topic, but I am not finding any guidance for the 9kHz exemption anywhere outside of this web site. This is regarding testing to EN 61326 (EN55011/CISPR 11). Is this still an exemption, and what can I cite when claiming the exemption? I have a lot of analog circuitry with just linear regulators and op amps (although some op amps are auto zeroing “choppers”….)

    Also, where is the flow chart in the article from?

    1. I agree. There is no exemption. I have had people explain to me that DC motors are exempt because of this limit. Who’s heard a motor whine on their radio? Any signal which changes state causes a broad splatter of frequencies as noise. If the splatter is infrequent then it’s average power is low and no-one cares. If it happens repeatedly it can be a problem. A 9kHz processor will probably produce at least 10 harmonics which are in the test band so it needs measuring, or rather “assessing”. You can assess as no problem, but it is at your (manufacturer’s) risk if it causes a problem and is investigated. The Eu EMC compliance is mandetory, not optional and has been for some time. To put a device on the market (even at home, and if you only make 1) it needs to be assessed. That means documentary evidence that it would pass if tested, or test results if it was formally done. If you don’t know how to calculate that your device is compliant then you’re not in a position to make that assessment and you should take it to a test house.

  21. Andy Eadie ,hi, I have some question about FCC, Exempted Devices list about Exempt Household Appliances for FCC, it means they do not need FCC certificate? and point 9. Same as the low frequency exemption for CE, if your device doesn’t generate and use timing signals or pulses at a rate in excess of 9,000 pulses (cycles) per second (9 kHz), then you can avoid emissions testing altogether. it means when a device rate is not excess 9KHZ, it also do not need any FCC certificate? thanks for your reply and assistance in advance.

  22. hi Andy,

    if I am building a device that includes a compoenent with working frequency higher than 9 K hz, but that component is CE marked, and it is the only radiation emitting compoenent in the device.

    still I need to have EMC test?

    Thanks.

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