What is FCC Class A vs. Class B?

fcc compliance Guide: Class A vs. Class B Devices and Related Requirements

By law, all electronic devices that may intentionally or unintentionally emit radio frequency (RF) signals must comply with the regulations of the FCC (Federal Communications Commission).

Overview of fcc part 15 Regulations

The testing standards for most electronic or digital devices come from Part 15 of the Code of Federal Regulations (CFR), which governs both intentional and unintentional RF/radiation-emitting devices. The FCC compliance process varies depending on the device classification and the level of compliance required—either Certification or a Supplier’s Declaration of Conformity (SDoC).

Differences Between FCC Class A and Class B Devices

What is a Class A Device?

Class A devices are designed specifically for commercial or industrial use and are not intended for general consumers.

- Looser emission limits, allowing for higher RF interference

- Must carry a label or display indicating "For Industrial/Commercial Use Only" or clearly state Class A status

- Not suitable for residential environments to avoid interference with consumer electronics

What is a Class B Device?

Class B devices are intended for use by the general public in residential environments, such as home electronics.

- Stricter emission limits to prevent interference with household devices like TVs and radios

- Includes most consumer devices with integrated circuits, clocks, oscillators, etc.

- Must carry a label indicating Class B classification

FCC Compliance testing and Requirements

SDoC (Supplier’s Declaration of Conformity)

Manufacturers must demonstrate that their products meet the strict standards under Subpart B of FCC Part 15. This typically involves testing by an accredited compliance laboratory.

Examples of Devices Requiring SDoC or Certification:

- Class B personal computers and internal components like power supplies and CPU boards

- Class B digital devices and their peripherals

- Broadband over power line (BPL) access equipment

- Class A digital devices, external power supplies, and peripherals

Radiated Emissions Testing (emi testing)

Radiated emissions testing measures the electromagnetic field strength unintentionally emitted by a device to determine if it complies with FCC emission limits.

- Non-compliant devices may interfere with the operation of other electronics

- If a device fails the test, root cause analysis and design modifications must be carried out before retesting

> For more on emi testing, refer to our training course: “The Ultimate Guide to EMI in Electronic Products”

Compliance Testing Consultation and Support

Ensuring your product complies with FCC regulations before market launch is critical. Non-compliant devices risk fines, legal liability, or prohibition from being sold.

As experts in FCC and international compliance testing, we can assist you with:

- Device testing

- Navigating the FCC certification process

- Ensuring full product compliance

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