For decades, specific absorption rate (SAR) testing has been the gold standard for measuring how the human body absorbs radiofrequency energy. It is a perfect solution for sub 6 GHz frequencies but as we push through 2026, frequencies are changing fast. If your device operates in the FR2 range (24.25 GHz to 52.6 GHz) or utilizes the 6 GHz capabilities of Wi-Fi 7, then traditional SAR testing is no longer technically applicable.

As frequencies climb above 6GHz, the radio frequency energy stops penetrating the body as deeply and begins to be absorbed primarily at the skin’s surface. This shift forced a regulatory change that requires devices above the standard SAR testing range to be fulfilled by Power Density Testing or another approved test. 

The Transition From Volume to Surface Testing

Radiofrequency energy is essential in the operation of a wireless device, products like smartphones, laptops, and wearable devices all emit radiofrequency waves. We are in constant contact with radiofrequency waves. Our bodies absorb these waves over time. The change in testing method is one way that lawmakers and governing bodies adapt to accommodate these changing times. 

At lower frequencies (under 6GHz), wavelengths are long enough to penetrate deep into human tissue. SAR measures the rate that this energy is absorbed into human tissue. The shift towards mmW and Wi-Fi 7 has changed the way that these devices interact with the human body. The wavelengths of mmW and Wi-Fi 7 do not penetrate the skin like their lower frequency counterparts, they absorb into the surface of the skin, measured in Watts per square meter (mmWave/Power Density Testing method) instead of Watts per kilogram (SAR testing method).

How is Power Density Testing done?

Unlike traditional SAR testing that uses phantom liquids, Power Density testing for high frequencies is focused on surface exposure. This test utilizes ultra-small high frequency probes that measure as close as 2mm from the device without distorting the signal. This scan is done at multiple heights to determine the exact phase and amplitude at the skin’s surface. Once the test area has been mapped, the “Peak spatial average power density” is calculated. Each test done on these devices is individually calibrated for the accuracy and integrity of the specific product.

RF Exposure Lab is here to help

As new wireless connection standards like Wi-Fi 7 become more prevalent, the importance of SAR and RF testing will only continue to grow. Manufacturers must adopt proactive strategies to ensure compliance, integrating testing early in the development process and partnering with experienced labs. By staying ahead of the curve, manufacturers can not only meet regulatory requirements but also deliver safe, high-performing products that capitalize on the latest technological advancements.

Our expert team knows that the SAR and RF testing landscape is constantly changing, which is why we do the work of staying on top of it so our clients don’t have to. Through our unique expertise and commitment to our clients, we guarantee accurate testing and results.

We offer SAR testing services for a variety of wireless devices including wireless modems, laptops, tablets, cell phones, medical products, 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.