8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.
Shield Your Body
Whole Body / General

SAR versus S(inc): What is the appropriate RF exposure metric in the range 1-10 GHz? Part II: Using complex human body models

Bioeffects Seen

Authors not listed · 2010

Share:

Safety standards should switch from SAR to power density measurements at 6 GHz for better protection.

Plain English Summary

Summary written for general audiences

Researchers compared two different methods for measuring radiofrequency radiation exposure safety limits in the 1-10 GHz range using computer models of adult and child heads. They found that the traditional SAR measurement works better at lower frequencies (1-3 GHz), while incident power density is more appropriate at higher frequencies (6-10 GHz), leading to a recommendation for switching measurement methods at 6 GHz.

Why This Matters

This study addresses a fundamental question in EMF safety standards: how should we measure exposure as frequencies get higher? The science demonstrates that our current approach of using SAR (specific absorption rate) becomes less reliable above 6 GHz, precisely where 5G and future wireless technologies operate. What this means for you is that safety standards may not adequately protect against the heating effects of higher-frequency radiation that penetrates less deeply but concentrates more intensely at the skin surface. The reality is that as wireless technology pushes into higher frequency bands, our safety metrics need to evolve accordingly. This research provides the scientific foundation for updating exposure limits, though whether regulatory agencies will act on these findings remains to be seen.

Exposure Information

A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 1-10 GHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 1-10 GHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Specific exposure levels were not quantified in this study.

Cite This Study
Unknown (2010). SAR versus S(inc): What is the appropriate RF exposure metric in the range 1-10 GHz? Part II: Using complex human body models.
Show BibTeX
@article{sar_versus_sinc_what_is_the_appropriate_rf_exposure_metric_in_the_range_1_10_ghz_part_ii_using_complex_human_body_models_ce782,
  author = {Unknown},
  title = {SAR versus S(inc): What is the appropriate RF exposure metric in the range 1-10 GHz? Part II: Using complex human body models},
  year = {2010},
  doi = {10.1002/bem.20574},
  
}
DOI: 10.1002/bem.20574PubMed: 20354998

Quick Questions About This Study

At higher frequencies, electromagnetic energy penetrates less deeply into tissue, concentrating near the surface. SAR averages energy over 10 grams of tissue, which becomes less meaningful when most energy absorption occurs in a much smaller surface area.
SAR measures energy absorbed per kilogram of tissue averaged over 10 grams, while incident power density measures the electromagnetic energy hitting the body surface. Each metric correlates better with tissue heating at different frequency ranges.
The study used both adult and 12-year-old child head models, finding similar patterns for both age groups. However, children's smaller head size and thinner tissues may result in different energy absorption patterns at higher frequencies.
Computer modeling showed SAR correlated better with tissue heating at 1-3 GHz, while power density worked better at 6-10 GHz. The 6 GHz breakpoint balances scientific accuracy with practical measurement considerations for safety standards.
Yes, many 5G frequencies operate above 6 GHz where this study suggests power density limits would be more appropriate than current SAR-based standards. This research provides scientific justification for updating regulatory exposure limits.