§  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]

   return arrow Back to Top