§ 1.1310   Radiofrequency radiation exposure limits.

   (a)  Specific  absorption  rate  (SAR)  shall  be used to evaluate the
   environmental impact of human exposure to radiofrequency (RF) radiation as
   specified in § 1.1307(b) within the frequency range of 100 kHz to 6 GHz
   (inclusive).

   (b) The SAR limits for occupational/controlled exposure are 0.4 W/kg, as
   averaged over the whole body, and a peak spatial-average SAR of 8 W/kg,
   averaged over any 1 gram of tissue (defined as a tissue volume in the shape
   of  a  cube).  Exceptions  are  the parts of the human body treated as
   extremities, such as hands, wrists, feet, ankles, and pinnae, where the peak
   spatial-average SAR limit for occupational/controlled exposure is 20 W/kg,
   averaged over any 10 grams of tissue (defined as a tissue volume in the
   shape of a cube). Exposure may be averaged over a time period not to exceed
   6 minutes to determine compliance with occupational/controlled SAR limits.

   (c) The SAR limits for general population/uncontrolled exposure are 0.08
   W/kg, as averaged over the whole body, and a peak spatial-average SAR of 1.6
   W/kg, averaged over any 1 gram of tissue (defined as a tissue volume in the
   shape of a cube). Exceptions are the parts of the human body treated as
   extremities, such as hands, wrists, feet, ankles, and pinnae, where the peak
   spatial-average SAR limit is 4 W/kg, averaged over any 10 grams of tissue
   (defined  as  a tissue volume in the shape of a cube). Exposure may be
   averaged over a time period not to exceed 30 minutes to determine compliance
   with general population/uncontrolled SAR limits.

   (d)(1) Evaluation with respect to the SAR limits in this section and in
   § 2.1093 of this chapter must demonstrate compliance with both the whole-body
   and peak spatial-average limits using technically supportable methods and
   exposure conditions in advance of authorization (licensing or equipment
   certification) and in a manner that permits independent assessment.

   (2) At operating frequencies less than or equal to 6 GHz, the limits for
   maximum permissible exposure (MPE), derived from whole-body SAR limits and
   listed in Table 1 of paragraph (e) of this section, may be used instead of
   whole-body SAR limits as set forth in paragraph (a) through (c) of this
   section  to  evaluate the environmental impact of human exposure to RF
   radiation as specified in § 1.1307(b), except for portable devices as defined
   in § 2.1093 as these evaluations shall be performed according to the SAR
   provisions in § 2.1093 of this chapter.

   (3) At operating frequencies above 6 GHz, the MPE limits shall be used in
   all cases to evaluate the environmental impact of human exposure to RF
   radiation as specified in § 1.1307(b).

   (4) Both the MPE limits listed in Table 1 of paragraph (e) of this section
   and the SAR limits as set forth in paragraph (a) through (c) of this section
   and in § 2.1093 of this chapter are for continuous exposure, that is, for
   indefinite  time  periods.  Exposure levels higher than the limits are
   permitted for shorter exposure times, as long as the average exposure over
   the specified averaging time in Table 1 is less than the limits. Detailed
   information on our policies regarding procedures for evaluating compliance
   with all of these exposure limits can be found in the FCC's OET Bulletin 65,
   “Evaluating  Compliance  with  FCC  Guidelines  for  Human Exposure to
   Radiofrequency Electromagnetic Fields,” and in supplements to Bulletin 65,
   all     available     at     the     FCC's    Internet    Web    site:
   http://www.fcc.gov/oet/rfsafety.

   Note to paragraphs (a) through (d): SAR is a measure of the rate of energy
   absorption due to exposure to RF electromagnetic energy. The SAR limits to
   be used for evaluation are based generally on criteria published by the
   American National Standards Institute (ANSI) for localized SAR in § 4.2 of
   “IEEE Standard for Safety Levels with Respect to Human Exposure to Radio
   Frequency  Electromagnetic  Fields,  3  kHz to 300 GHz,” ANSI/IEEE Std
   C95.1-1992, copyright 1992 by the Institute of Electrical and Electronics
   Engineers, Inc., New York, New York 10017. The criteria for SAR evaluation
   are  similar to those recommended by the National Council on Radiation
   Protection and Measurements (NCRP) in “Biological Effects and Exposure
   Criteria for Radiofrequency Electromagnetic Fields,” NCRP Report No. 86,
   § 17.4.5, copyright 1986 by NCRP, Bethesda, Maryland 20814. Limits for whole
   body SAR and peak spatial-average SAR are based on recommendations made in
   both of these documents. The MPE limits in Table 1 are based generally on
   criteria published by the NCRP in “Biological Effects and Exposure Criteria
   for Radiofrequency Electromagnetic Fields,” NCRP Report No. 86, § § 17.4.1,
   17.4.1.1, 17.4.2 and 17.4.3, copyright 1986 by NCRP, Bethesda, Maryland
   20814. In the frequency range from 100 MHz to 1500 MHz, these MPE exposure
   limits for field strength and power density are also generally based on
   criteria recommended by the ANSI in § 4.1 of “IEEE Standard for Safety Levels
   with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3
   kHz to 300 GHz,” ANSI/IEEE Std C95.1-1992, copyright 1992 by the Institute
   of Electrical and Electronics Engineers, Inc., New York, New York 10017.

   (e) Table 1 below sets forth limits for Maximum Permissible Exposure (MPE)
   to radiofrequency electromagnetic fields.

   Table 1—Limits for Maximum Permissible Exposure (MPE)
   Frequency range
   (MHz) Electric field strength
   (V/m) Magnetic field strength
   (A/m) Power density
   (mW/cm^2) Averaging time
   (minutes)
             (A) Limits for Occupational/Controlled Exposure
             0.3-3.0                   614   1.63     *100  6
             3.0-30                 1842/f 4.89/f *900/f^2  6
             30-300                   61.4  0.163      1.0  6
             300-1,500                               f/300  6
             1,500-100,000                               5  6
             (B) Limits for General Population/Uncontrolled Exposure
             0.3-1.34                  614   1.63     *100 30
             1.34-30                 824/f 2.19/f *180/f^2 30
             30-300                   27.5  0.073      0.2 30
             300-1,500                              f/1500 30
             1,500-100,000                             1.0 30

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

   (1) Occupational/controlled exposure 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 a person is transient through a location where
   occupational/controlled limits apply provided he or she is made aware of the
   potential for exposure. The phrase fully aware in the context of applying
   these exposure limits means that an exposed person has received written
   and/or verbal information fully explaining the potential for RF exposure
   resulting  from his or her employment. With the exception of transient
   persons,  this  phrase  also means that an exposed person has received
   appropriate training regarding work practices relating to controlling or
   mitigating his or her exposure. Such training is not required for transient
   persons,  but  they must receive written and/or verbal information and
   notification (for example, using signs) concerning their exposure potential
   and appropriate means available to mitigate their exposure. The phrase
   exercise control means that an exposed person is allowed to and knows how to
   reduce or avoid exposure by administrative or engineering controls and work
   practices, such as use of personal protective equipment or time averaging of
   exposure.

   (2) General population/uncontrolled exposure limits apply in situations in
   which the general public may be exposed, or in which persons who 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.

   (3) Licensees and applicants are responsible for compliance with both the
   occupational/controlled    exposure    limits    and    the    general
   population/uncontrolled exposure limits as they apply to transmitters under
   their  jurisdiction. Licensees and applicants should be aware that the
   occupational/controlled exposure limits apply especially in situations where
   workers may have access to areas in very close proximity to antennas and
   access to the general public may be restricted.

   (4) In lieu of evaluation with the general population/uncontrolled exposure
   limits, amateur licensees authorized under part 97 of this chapter and
   members of his or her immediate household may be evaluated with respect to
   the  occupational/controlled exposure limits in this section, provided
   appropriate  training and information has been provided to the amateur
   licensee and members of his/her household. Other nearby persons who are not
   members of the amateur licensee's household must be evaluated with respect
   to the general population/uncontrolled exposure limits.

   [ 78 FR 33650 , June 4, 2013]

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