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IEC/IEEE 63195-1:2022—Assessment of Power Density of Human Exposure to Radio Frequency Fields from Wireless Devices in Close Proximity to the Head and Body (Frequency Range of 6 GHz to 300 GHz)—Part 1: Measurement Procedure

Preview: Learn more about IEC/IEEE 63195-1 and its measurement procedure for assessing power density from wireless devices used close to the head or body.

IEC/IEEE 63195-1:2022 specifies measurement protocols and test procedures for repeatable and reproducible assessment of radiofrequency power density incident on the human head or body from wireless communication devices. It covers the frequency range from 6 GHz to 300 GHz and is intended to produce conservative exposure estimates with a stated measurement uncertainty.

The document is an IEC/IEEE dual-logo international standard developed for devices operating close to the body as millimetre-wave and other high-frequency wireless technologies became more common. It supplies an engineering method for determining conformity with an applicable maximum power-density requirement; it does not itself select the legal exposure limit.

Scope and covered devices

The procedures apply to hand-held and body-worn RF transmitting communication devices used by a significant majority of the population. Devices can contain one or several transmitters or antennas and can operate with their radiating structures at distances up to 200 mm from the head or body.

Covered categories include mobile telephones, radio transmitters in personal, desktop, and laptop computers, and multi-band or multi-antenna devices. The method also addresses configurations involving accessories, combined transmitting and non-transmitting equipment, belt clips, and transmitters embedded in garments. Its procedures may be adaptable to non-communication devices used close to the body, but those products are outside the stated scope.

The standard does not apply to measurements of devices or objects intended to be implanted in the body. Product-specific regulation can impose additional restrictions on test positions, operating modes, separation distances, averaging areas, or compliance reporting.

Why power density is used

At frequencies above about 6 GHz, RF energy is absorbed predominantly in superficial tissues. Exposure frameworks therefore use incident or absorbed power-density quantities, with spatial and temporal averaging, rather than relying only on the mass-averaged SAR procedures traditionally used at lower frequencies.

The relevant power-density metric and limit must be identified from the applicable regulatory or exposure framework. The standard’s task is to define how the incident field is measured and processed so that results are technically sound, conservative, and comparable between laboratories.

There is an intentional overlap between 6 GHz and 10 GHz with IEC/IEEE 62209-1528:2020, which permits SAR assessment through 10 GHz. The published scope notes that ICNIRP and IEEE exposure guidance uses power density as the conformity metric in this overlap, while SAR may be accepted where local regulatory requirements allow it. The chosen method must therefore match the governing jurisdiction.

Measurement concept

A close-proximity device can produce a highly non-uniform field containing propagating, reactive, and evanescent components. A single broadband reading at one convenient point cannot adequately characterise that exposure. The measurement system instead scans an evaluation surface near the device and reconstructs the spatial distribution of the electromagnetic field or power density.

The evaluation surface represents the location at which conformity is assessed relative to the body or the device. Its placement, dimensions, sampling grid, and relationship to the radiating structure are important because small changes can alter a near-field result. The test arrangement must reproduce the intended use and the separation conditions required by the applicable compliance regime.

Measurement equipment

The system requires probes and positioning equipment suitable for the frequency, field composition, spatial gradients, and expected level. Probe dimensions and sensor spacing affect spatial resolution; isotropy, linearity, frequency response, dynamic range, noise, and cross-axis response affect accuracy. Mechanical positioning and knowledge of the probe’s effective measurement location are also significant.

The measurement setup must be characterised and validated. Calibration must be traceable and appropriate to the measured quantities and frequencies. System checks are used to show that the scanner, probe, reconstruction process, and data handling produce acceptable results before an unknown device is assessed.

Device preparation and test configurations

The equipment under test must operate in the modes capable of producing the highest relevant exposure. Frequency channel, modulation, bandwidth, antenna configuration, conducted or radiated power, beam state, duty factor, power control, and thermal behaviour can all affect the result. Test software or call-box control may be required to hold a reproducible maximum condition.

All relevant device positions and accessories must be considered. A product used at the face, on the body, in a computer, or within clothing can require different configurations. The compliance record should distinguish tested positions from conditions covered by technical analysis or conservative bounding.

Modern arrays and beamforming systems require particular care. The assessment must account for beam direction, codebook or antenna states, simultaneous transmission, and any averaging or power-control algorithm relied upon. A short scan of a non-representative state cannot be assumed to bound a dynamic system.

Spatial assessment and averaging

Measured field data are converted to the specified power-density quantity and evaluated over the spatial averaging area prescribed by the applicable exposure limits. The assessment must locate the maximum averaged result, not merely the maximum sampled point or an average over an arbitrarily chosen surface.

The scan extent and resolution must be sufficient to capture narrow beams and local maxima. Interpolation, reconstruction, and spatial averaging must not smooth away a relevant peak. Edge effects can indicate that the scan area should be extended.

Multiple frequencies and transmitters

Where several transmitters operate simultaneously, the combined exposure must be assessed under the summation rules of the applicable limits. Contributions below 6 GHz may require SAR measurement using IEC/IEEE 62209-1528 or IEC/IEEE 62209-3, while contributions at and above 6 GHz use the power-density procedure. Mixed-metric results must be combined as the regulator requires.

Measurement uncertainty

An uncertainty budget is essential because the compliance result depends on the probe, calibration, positioning, sampling, reconstruction, field variability, device power, drift, test repeatability, and other influence quantities. Components are quantified and combined according to the standard’s procedure, and the reported result must be interpreted using the compliance rule required by the relevant authority.

Uncertainty is not a reason to omit a potentially significant configuration. Where gradients are steep or the result is close to the limit, improved resolution, additional measurements, or a more conservative test condition may be needed.

Relationship to Part 2

IEC/IEEE 63195-2 provides a complementary computational route using validated numerical methods. Measurement is often preferred for final hardware and regulatory testing, while computation can assist design, antenna-state analysis, and cases where a probe cannot readily access the required surface. The two parts pursue the same objective but have different validation and uncertainty requirements.

Practical significance

IEC/IEEE 63195-1 is the principal international measurement procedure for close-proximity wireless devices assessed by power density from 6 GHz to 300 GHz. It extends exposure testing into the millimetre-wave range with controlled scanning, field reconstruction, spatial averaging, validation, and uncertainty analysis.

For RF radiation safety, the standard should be understood as a measurement method within a larger conformity system. Correct use depends on the applicable exposure limit, a complete inventory of device modes and antennas, representative maximum-power operation, appropriate evaluation geometry, competent uncertainty treatment, and any additional requirements of the equipment-authorisation authority.