Everything You Should Know About SAR Standards

  • Post category:SAR Testing
Everything You Should Know About SAR Standards

As a manufacturer, are you familiar with SAR standards? Do you have an in-depth understanding of what goes into ensuring that your products are safe for consumer use and will be allowed into markets in all countries in which you plan to sell the product? If the answer to these questions is no, you’re not alone. Many manufacturers don’t have in-depth knowledge of SAR standards because it’s the job of SAR testing labs to have this knowledge and work with you to prove the compliance of your devices. Keep reading to learn more about these standards as well as how RF Exposure Lab can make testing easy for you.

The basics of SAR testing

SAR, or specific absorption rate, is a measurement for the quantity of radio frequency that a wireless device generates and that is absorbed by the body when the device is used. Because only some RF energy is absorbed by the body while the rest simply passes through, SAR testing evaluates both the amount of RF energy absorbed by the body from the wireless device and the rate at which it’s absorbed by body tissue exposed to it. RF energy heats tissue when it comes into contact with it, so operating these devices without testing to ensure their safety can cause harm to operators.

SAR value is indicated by watts per kilogram (W/kg) or milliwatts per gram (mW/g). RF exposure is a measure of both the electric and magnetic field strength and power density for transmitters operating at frequencies ranging from 300 kilohertz (kHz) to 100 gigahertz (GHz).

SAR testing provides manufacturers of wireless devices with a clear way to measure the RF exposure characteristics of wireless devices and prove that they meet the FCC’s safety guidelines. Wireless devices are required to be evaluated to meet the RF exposure limits that have been determined by the FCC and international governmental agencies, such as those in Canada and Europe. 

When is SAR testing necessary?

Any wireless product that emits RF energy is required to prove compliance with SAR standards set forth by the FCC or regulatory bodies of whatever country it is intended to be marketed in. In the US, the FCC requires that SAR testing to be conducted on all wireless devices with RF radiating parts that will be used closer than 20 cm (about 8 inches) from the body or head.

There are other factors that determine whether SAR testing is necessary as well. In Canada and the US, devices must prove compliance with SAR standards depending on:

  • The distance between the user and the device.
  • The device’s operating power.
  • The frequency in which the device operates.

In Europe, however, these factors differ. Any wireless device that operates at a power of 20mW or higher must undergo SAR testing. 

Keep in mind that even when it’s determined that a device needs to be tested, SAR value limits and guidelines defining what is safe will vary between devices. The FCC has classified wireless devices as fixed, mobile, or portable products depending on how they are installed and used. Devices are categorized based on the following criteria:

  • Fixed products: devices with an antenna that are permanently attached to a structure and can’t be easily relocated.
  • Mobile products: devices that can be easily moved from one location to another and are used more than 20cm away from the body.
  • Portable products: like mobile products, these are devices that can be easily moved from one place to another, but portable products are used within 20 cm of the body.

Even within these classifications, some devices will have exceptions determining their SAR value limits. For example, it’s a common misunderstanding that handheld devices can be classified as mobile even though they may be used within 20cm of the body, but all handheld devices must be evaluated for SAR against the extremity SAR values.

SAR Standards Internationally – US, EU, and CAN

SAR exposure limits vary from country to country. In the US and Canada, mobile devices must meet a limit of 1.6W/Kg measured from 1g tissue volume. This means that for a device to gain FCC or ISED certification and be allowed to be sold in either country, the device’s maximum SAR level cannot exceed this. In the EU, a device’s SAR limit cannot exceed 2.0W/Kg measured from 10g tissue volume.

Keep in mind that Canada’s SAR standards are the most strict. Canadian requirements include CE and FCC certification requirements along with requirements of their own. This makes obtaining certification in Canada more challenging than in other countries. In addition to this, certification can be further complicated by their strict millimeter-wave regulations.

The SAR test reports required for the device or devices you’ve manufactured will depend on the countries where the product will be sold. Because countries have varying SAR standards and limits, they will require different reports. Remember that if your product fails to meet SAR regulations in a country or region, you will not have access to that market.

Work With a Lab With Expert Knowledge of SAR Standards – RF Exposure Lab

We are a world-class leader in SAR testing committed to providing our clients with accurate SAR testing and technical competence. This commitment is shown in our knowledge of SAR standards as well as our A2LA accreditation. We’ve helped many clients conduct testing for devices sold in various countries, making the process easier and more efficient.

We go above and beyond to make sure our clients understand what we do and assist them in understanding what SAR testing is required for their products. Through our unique expertise and commitment to our clients, we guarantee accurate SAR testing.

We offer SAR testing services for a variety of wireless devices including millimeter wave devices, near field devices, and much more. If you’re looking for SAR testing help provided with speed, accuracy, expertise, and integrity, contact us to get a quote for our services.