Value chain · CLM-1170
In plain terms
In the 2020 international guidelines, besides the half-hour whole-body limit there is a six-minute limit on the hottest spot on the body, 40 watts per square metre for the public and 200 for workers at these frequencies, and a rule for bursts shorter than six minutes that lets a single brief pulse carry at most about 720 joules per square metre for the public.
The claim as recorded
ICNIRP 2020's local reference levels at 2.45 and 5.8 GHz are the >2-6 GHz row of Table 6, "Reference levels for local exposure, averaged over 6 min": 200 W/m2 occupational and 40 W/m2 general public, taken as "peak spatial Sinc, Einc or Hinc, over the projected whole-body space" (the 4 cm2 averaging applies only above 6 GHz); for exposures shorter than six minutes Table 7 limits the incident energy density to 200 x "0.36[0.05+0.95(t/360)0.5]" kJ/m2 occupational and 40 x the same bracket for the public, so that "exposure from any pulse, group of pulses, or subgroup of pulses in a train, as well as from the summation of exposures (including non-pulsed EMFs), delivered in t seconds, must not exceed these reference level values"; behind them are local SAR basic restrictions of 10 and 2 W/kg (head and torso) and 20 and 4 W/kg (limbs), "averaged over a 10-g cubic mass" and 6 min.
Evidence behind this: T1-the normative instrument quoted for its own requirement; local and brief-exposure levels with their averaging rules at the page.
Scope and limits
THE 40 AND 200 W/m2 ARE LOCAL, SIX-MINUTE, PEAK-SPATIAL LEVELS AND DO NOT REPLACE THE 10 AND 50 W/m2 WHOLE-BODY LEVELS - both must be met. The 4 cm2 averaging often quoted for "local" limits does not apply below 6 GHz in this guideline. The Table 7 bracket's exponent is a superscript the layer flattens; read at the page.
What it assumes
"Peak spatial ... over the projected whole-body space" means the highest point value over the body's projected area, as the note reads.
Where it comes from
PDF 15 / printed 496: "Reference levels for local exposure, averaged over 6 min, to electromagnetic fields from 100 kHz to 300 GHz (unperturbed rms values)" (normalised); ">2 - 6 GHz" rows "6 GHz NA NA 200" (occupational) and "6 GHz NA NA 40" (general public) (normalised; crop read); note 3 "Sinc, Einc, and Hinc are to be averaged over 6 min, and where spatial averaging is specified in Notes 6" - 7, "over the relevant projected body space" (raw; normalised); note 5 "For frequencies of >30 MHz to 6 GHz: (a) within the far-field zone, compliance is demonstrated if one of peak spatial Sinc, Einc or Hinc, over the projected whole-body space, does not exceed the above reference level values (only one is required)" (normalised). PDF 16 / printed 497: "Reference levels for local exposure, integrated over intervals of between >0 and <6 minutes, to electromagnetic fields from 100 kHz to 300 GHz (unperturbed rms values)" (normalised); ">2 - 6 GHz" rows "6 GHz 200" and "6 GHz 40" each times "0.36[0.05+0.95(t/360)0.5]" (normalised; raw; the 0.5 is a superscript); note 2 "exposure from any pulse, group of pulses, or subgroup of pulses in a train, as well as from the summation of exposures (including non-pulsed EMFs), delivered in t seconds, must not exceed these reference level values" (normalised). PDF 10 / printed 491, Table 2 (crop read): "Occupational 100 kHz to 6 GHz 0.4 10 20 NA"; "General public 100 kHz to 6 GHz 0.08 2 4 NA" (normalised); "Local SAR and Sab exposures are to be averaged over 6 min" (raw); "Local SAR is to be averaged over a 10-g cubic mass" (raw). Recomputed: at t = 360 s the bracket is 1.0, so 40 x 0.36 = 14.4 kJ/m2 = 40 W/m2 x 360 s and 200 x 0.36 = 72 kJ/m2 = 200 W/m2 x 360 s, Table 7 meeting Table 6 at six minutes; at t -> 0 the bracket is 0.05, giving 0.72 kJ/m2 public and 3.6 kJ/m2 occupational per brief burst; 200 / 40 = 5.
Basis: W/m2 incident power density, 6-min average, peak spatial over the projected whole-body space; kJ/m2 incident energy density over t seconds, 0 < t < 360; W/kg local SAR over 10 g and 6 min
Cite this
energyaperture.com/c/clm-1170
CLM-1170, Energy Aperture, as of 2020-05.
Connected records
Other published records linked to this one. A list, not a judgement.
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