Electromagnetic Regulations

CONTACT US

WATCH VIDEO

Cell La Vie title

You are invited to review the below article regarding electromagnetic radiation regulations. Additional updates, posts and Q&A can be found in the Forum section of this site.

 

 

Overview

 
Exposure standards and guidelines have been developed by various organizations and countries over the past several decades.  In North America and most of Europe exposure standards and guidelines have generally been based on exposure levels where effects considered harmful to humans occur.  Safety factors are then incorporated to arrive at specific levels of exposure to provide sufficient protection for various segments of the population.

 

Not all standards and guidelines throughout the world have recommended the same limits for exposure.   For example, some published exposure limits in Russia and some eastern European countries have been generally more restrictive than existing or proposed recommendations for exposure developed in North America and other parts of Europe.  This discrepancy may be due, at least in part, to the possibility that these standards were based on exposure levels where it was believed no biological effects of any type would occur.  This philosophy is inconsistent with the approach taken by most other standards-setting bodies which base limits on levels where recognized hazards may occur and then incorporate appropriate safety margins to ensure adequate protection.

 

U.S. federal, state and local governmental agencies and other organizations have generally relied on RF exposure standards developed by expert non-government organizations such as ANSI, the Institute of Electrical and Electronics Engineers (IEEE) and the National Council on Radiation Protection and Measurements (NCRP).

 

The ANSI/IEEE standards have been widely used and cited and have served as the basis for similar standards in the United States and in other countries.  

In addition to NCRP and ANSI/IEEE, other organizations and countries have issued exposure guidelines. For example, several European countries are basing guidelines on exposure criteria developed by the International Committee on Nonionizing Radiation Protection (ICNIRP). The ICNIRP guidelines are also derived from an SAR threshold of 4 W/kg (for adverse effects) and are similar to the 1992 ANSI/IEEE and NCRP recommendations with certain exceptions.  For example, ICNIRP recommends somewhat different exposure levels in the lower and upper frequency ranges and for localized exposure due to such devices as hand-held cellular telephones.

 

Many, but not all, countries have based exposure recommendations on the same general concepts and thresholds as those used by the NCRP, ANSI/IEEE and ICNIRP.  Because of differences in international standards, the World Health Organization (WHO), as part of its EMF Project (discussed earlier), has initiated a program to try and develop an international framework for RF safety standards. 
 
 

Safety Limits

 

Most radiofrequency safety limits are defined in terms of the electric and magnetic field strengths as well as in terms of power density.  For lower frequencies, limits are more meaningfully expressed in terms of electric and magnetic field strength values, and the indicated power densities are actually "far-field equivalent" power density values 

 

FCC Limits for Maximum Permissible Exposure (MPE)

 

(A)  Limits for Occupational/Controlled Exposure

 

Frequency                        Electric Field             Magnetic Field          Power Density        Averaging Time

Range

(MHz)

Strength

(V/m)

(E)

Strength

(A/m)

(H)

(S) (mW/cm2)

|E|2, |H|2  or S (minutes)

 

0.3-3.0

 

614

 

 

1.63

 

 

(100)*

 

6

3.0-30

1842/f

 

4.89/f

 

(900/f2)*

6

30-300

61.4

 

0.163

 

1.0

6

300-1500

--

 

--

 

f/300

6

1500-100,000

--

 

--

 

5

6

 

 

 

(B)  Limits for General Population/Uncontrolled Exposure

 

Frequency                        Electric Field             Magnetic Field          Power Density        Averaging Time

Range

(MHz)

Strength

(V/m)

(E)

Strength

(A/m)

(H)

(S) (mW/cm2)

|E|2, |H|2  or S (minutes)

 

0.3-1.34

 

614

 

 

1.63

 

 

(100)*

 

30

1.34-30

824/f

 

2.19/f

 

(180/f2)*

30

30-300

27.5

 

0.073

 

0.2

30

300-1500

--

 

--

 

f/1500

30

1500-100,000

--

 

--

 

1.0

30

f = frequency in MHz                                          *Plane-wave equivalent power density

 

NOTE 1: Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their employment provided those persons are fully aware of the potential for exposure and can exercise control over their exposure. Limits for occupational/controlled exposure also apply in situations when an individual is transient through a location where occupational/controlled limits apply provided he or she is made aware of the potential for exposure.

 

NOTE 2: General population/uncontrolled exposures apply in situations in which the general public may be exposed, or in which persons that are exposed as a consequence of their employment may not be fully aware of the potential for exposure or cannot exercise control over their exposure.

 

For more information see: FCC's OET Bulletin 65, “Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields,” August 1997


Link | Download

 

 

 

ICNIRP Basic Restrictions for time varying electric and magnetic fields

 

For frequencies up to 10 GHz*

 

 

Exposure

 

Current density for head and trunk

Whole-body average SAR

Localized SAR (head and trunk)

 

Localized SAR

characteristics

Frequency range

(mA/m2) (rms)

(W/kg)

(W/kg)

(limbs) (W/kg)

Occupational

up to 1 Hz

40

exposure

1–4 Hz

40/f

 

4 Hz–1 kHz

10

 

1–100 kHz

f /100

 

100 kHz–10 MHz

f /100

0.4

10

20

 

10 MHz–10 GHz

0.4

10

20

General public

up to 1 Hz

8

exposure

1–4 Hz

8/f

 

4 Hz–1 kHz

2

 

1–100 kHz

f /500

 

100 kHz–10 MHz

f /500

0.08

2

4

 

10 MHz–10 GHz

0.08

2

4

*Note:

  1. f is the frequency in hertz.
  2. Because of electrical inhomogeneity of the body, current densities should be averaged over a cross-section of 1 cm2    perpendicular to the current direction.
  3. For frequencies up to 100 kHz, peak current density values can be obtained by multiplying the rms value by 1.414. For pulses of duration tp the equivalent frequency to apply in the basic restrictions should be calculated as f=1/(2tp).
  4. For frequencies up to 100 kHz and for pulsed magnetic fields, the maximum current density  associated with the pulses can be calculated from the rise/fall times and the maximum rate of change of magnetic flux density. The induced current density can then be compared with the appropriate basic restriction.
  5. All SAR values are to be averaged over any 6-min period.
  6. Localized SAR averaging mass is any 10 g of contiguous tissue; the maximum SAR so obtained should be the value used for the estimation of exposure.
  7. For pulses of duration tp   the equivalent frequency to apply in the basic restrictions should be calculated as f=1/(2tp). Additionally, for pulsed exposures in the frequency range 0.3 to 10 GHz and for localized exposure of the head, in order to limit or avoid auditory effects caused by thermoelastic expansion, an additional basic restriction is recommended. This is that the SA should not exceed 10 mJ/kg for workers and 2mJ/kg for the general public, averaged over 10 g tissue.

 

 

ICNIRP Reference levels for occupational exposure to time-varying electric and magnetic fields (unperturbed rms values)*

 

 

Organizations

 

Federal Communication Commission

 

The Federal Communications Commission (FCC) is an independent United States government agency. The FCC was established by the Communications Act of 1934 and is charged with regulating interstate and international communications by radio, television, wire, satellite and cable. The FCC's jurisdiction covers the 50 states, the District of Columbia, and U.S. possessions.

 

More info on FCC can be found here

 

 

International Commission on Non-Ionizing Radiation Protection

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) is an independent scientific organization whose aims are to provide guidance and advice on the health hazards of non-ionizing radiation exposure.

 

ICNIRP was established to advance non-ionizing radiation protection for the benefit of people and the environment. It develops international guidelines on limits of exposure to non-ionizing radiations which are independent and science based; provides science based guidance and recommendations on protection from non-ionizing radiation exposure; establishes principles of non-ionizing radiation protection for formulating international and national protection programs.

 

ICNIRP is a non-governmental organization in non-ionizing radiation in formal relations with the World Health Organization and the International Labour Office. It maintains a close liaison and working relationship with all international bodies engaged in the field of non-ionizing radiation protection, and interacts with radiation protection professionals worldwide through its close collaboration with the International Radiation Protection Association and its national societies.

 

Work is conducted in four standing committees - on Epidemiology, Biology, Physics and Optical Radiation - and in conjunction with appropriate international and national health and research organizations as well as universities and other academic institutions.

 

More info on ICNIRP can be found here
 
 
Return to top

Attention: open in a new window. Print | E-mail