The FCC has launched a review of its rules covering health and safety issues related to exposure to RF emissions from radio transmitters.
The review of RF exposure limits and human exposure to RF electromagnetic fields is an effort to ensure FCC rules comply with the agency’s “environmental responsibilities and requirements,” as well as make sure the public is protected from adverse effects of RF exposure, the agency said.
The agency effort, which includes a Report and Order, a Further Notice of Proposed Rule Making and a Notice of Inquiry, was made public March 29. The Report and Order addresses technical issues and semantics raised in 2003 that revise agency regulations implementing the National Environmental Policy Act, which requires the government to evaluate the effects of its actions on the human environment.
In the order, the agency adopted rules giving licensees and grantees permission to show that they comply with the FCC’s RF exposure rules based on specific absorption rate (SAR) at frequencies below 6GHz in lieu of maximum permissible exposure (MPE) for fixed and mobile transmitters. By providing SAR as an alternative, the agency said it might be possible for those required to show compliance to reduce expenses.
The order also classifies the outer ear as an extremity because of its similarity to other body parts, like hands and feet, that currently are categorized as extremities. The reclassification of the outer ear should eliminate unnecessary compliance costs, the agency said.
FCC rules draw a distinction between the SAR limit of 1.6W/kg averaged over any one gram cube of tissue, and extremities, which prior to the inclusion of the outer ear included only hands wrist, feet and ankles. The SAR limit for extremities is 4W/kg as averaged over any 10g cube. The rules also draw a distinction between the limit of the general public and occupational exposure.
The Further Notice proposes new power- and distance-based exemptions used to determine if a routing RF evaluation is required: procedures, such as the use of signs, labels and barriers, to mitigate RF levels exceeding allowable limits following an evaluation; and clarification of the calculation or measurement methodologies used in the RF evaluation process, the agency said.
According to the FCC, the goal of the Further Notice is to ensure appropriate protection for the public while not creating “undue burden” on industry. The agency said it must “determine whether the overall costs of the regulation are outweighed by the benefit to consumers, workers and other members of the public.” The FCC is seeking comment on the questions raised in the Further Notice to “weigh those costs and benefits of our proposed rules,” it said.
The Further Notice proposes a general exemption criterion of 1mW for any single transmitter independent of frequency and service type. It also proposes a minimum 2cm separation between multiple transmitters operating up to 1mW. The agency is seeking comment on whether multiple transmitters using the exemption could exceed acceptable exposure limits.
The Further Notice also proposes other exemptions including a “quantitatively exempt” multiple transmitting antennas configurations and transmitters, where RF exposure determined during a previous evaluation may be significant based on application of transmitter frequency-threshold ERP information presented in a table in the Further Notice and a proposed formula that takes into account the fractional contribution of each antenna to the exemption threshold.
The Notice of Inquiry seeks comment on whether or not the agency’s RF exposure limits and policies need to be revised. In the notice, the FCC said while it remains confident in its RF exposure limits, it is nonetheless seeking comment on whether it should consider alternative limits.
In the Notice of Inquiry, the FCC is seeking analysis of technical differences between its existing exposure limits and more recent standards-setting activities and research, including partial- and whole-body averaging of exposure, averaging time, averaging area, peak pulsed-RF fields, constant currents, frequency range and conductive implanted objects, the Notice of Inquiry said.
The Notice of Inquiry also wants comments on: how to better provide the public with information about RF exposure; conventional exposure limits vs. other precautionary approaches; how the agency might be able to improve the process of developing evaluation procedures; and the FCC’s current portable device separation distance policy used to determine compliance.
Comments will be due 90 days following publication in the Federal Register; reply comments are due 150 days after that publication.