SAR Testing

Exposure excessive levels of radio frequency (RF) energy can damage human tissue. To minimize the potential for damaging exposure to RF Energy, many countries around the world have adopted standards that limit the amount of RF exposure allowed from transmitters of all types. BACL can determine if your product meets those requirements.

RF exposure from licensed radio devices or from certain classes of unlicensed wireless devices that are (or may be) used within 20 cm of the human body (i.e., from devices that are worn on or close to the body, or are hand-held) are subject to SAR requirements. The RF exposure from such devices is evaluated using one or more “phantoms” whose shapes and tissue simulant liquids simulate the electrical characteristics of the human head or body.

During SAR testing, the RF energy penetrating the applicable “phantom” is monitored by using a robotic system that precisely positions probes that measure the Specific Absorption Rate (SAR) of RF Energy emitted from the product in Watts per kilogram (or milliWatts per gram) of tissue.  Therefore, SAR, is a measure of the heating value of radiated RF energy on human tissue.

In the United States, the FCC regulates SAR under 47 CFR Part 2, Section 2.1093.  The equivalent SAR requirements for Canada are stated ISED Canada RSS-102.  Products intended for general use in the USA and Canada must meet a SAR limit of 1.6 mW/g averaged over one gram of tissue in any part of the head or body, and 4 mW/g averaged over 10 grams for hands, wrists, feet, and ankles.

In Europe (i.e., in the EU, EFTA, and EEA nations), the RF exposure limits are based upon the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits that are used in various Standards (e.g., EN 50360, EN 50566, etc.) that are harmonized under the 2014/53/EU Radio Equipment Directive [RED].  These Harmonized standards cover the most common products such as cell phones and RFID devices.  Products intended for general use must meet a SAR limit of 2.0 W/kg averaged over 10 grams of tissue in any part of the head or body, and 4 W/kg averaged over 10 grams for limbs.  Additionally, the “whole body” exposure is required to be limited to 0.08 W/kg.  The methods of RF exposure evaluation in the EU are similar but not identical to those in the US.

In order to assist our customers with compliance to regulations that limit RF exposure, BACL offers comprehensive Specific Absorption Rate (SAR) testing for unlicensed wireless and licensed radio devices.  BACL Sunnyvale’s ISO/IEC 17025 Scope of Accreditation includes 27different SAR Standards, including all of the SAR Standards required in the USA, Canada, Japan, Europe (i.e., in the EU, EFTA, and EEA nations), Australian / New Zealand, Korea, and in many other nations.

Due to the recent advances in both Licensed Radio and Unlicensed Wireless Technologies (including but not limited to 5G LTE and massive MIMO), BACL Sunnyvale upgraded its already comprehensive SAR and HAC testing Capabilities to include a state-of-the-art, high-end SPEAG DASY6 SAR Test System that is equipped with a new, very-high accuracy (i.e.,  better than +/- 0.02 mm in all three axes) TX90L robotic system and its controller, new phantoms (i.e., the Twin SAM and ELI Phantoms), new measurement probes, new calibration and validation dipoles, and the latest SPEAG DASY Version 5.2 and 6.0 test software.  The System is supported with the latest versions of call box hardware (i.e., the Rohde & Schwarz CMW 500 and the Rohde & Schwarz CMU200) and software, vector-modulation signal generators and transmit antennas, a vector network analyzer, and the new Broadband SAR Tissue Simulant Liquids that simulate both head and body tissues.  Because this System includes a large support frame, it is ready for the “in-air” tests that will eventually be required for making power density SAR measurements on 5G Systems that will operate at frequencies up to 110 GHz.

In order to ensure the highest levels of accuracy and repeatability, the entire System is housed in a dedicated RF Shielded Enclosure that is equipped with EMI Facility Filters that provide AC Power directly to the System.

For assistance in obtaining SAR testing and/or HAC testing, please contact our friendly Sales Team for information.