In a Notice of Inquiry, the FCC proposes to reopen the controversial question of radiofrequency exposure limits.

Do cell phones cause cancer?

Those on both sides of the question will carefully parse the FCC’s 201-page “First Report and Order, Further Notice of Proposed Rule Making and Notice Of Inquiry,” as the agency wades again into one of its murkiest controversies: what effect do radio waves have on health?

The FCC has had rules limiting RF (radiofrequency) exposure for decades. Other bodies recommend numerical exposure limits, that being outside the FCC’s expertise. The FCC nevertheless decides which recommendations to adopt, what kinds of transmitters must be tested for compliance, and how those tests are to be carried out.

The proper limits for safe exposure are a matter of considerable debate – a debate that helped to prompt the FCC’s current action. The question is controversial in part because of disagreement over how radio waves affect bodily tissue.

Everyone agrees that RF exposure causes heating. A microwave oven works simply by spraying your popcorn with radio waves. A cell phone held up your ear has a similar effect on your brain, in principle, although at much lower energy levels. The FCC directly regulates the amounts of heating permitted from cell phones and many other devices that are used within eight inches (that’s 20 centimeters, for our non-U.S. readers) of the body and operate below 6 GHz. Required tests assess the so-called “specific absorption rate” (SAR) by measuring actual heating of a model or manikin representing the affected part of the body. Devices operating above 6 GHz or used more than eight inches away, such as vehicle-mounted radios, instead are subject to a much simpler test of energy reaching the user, called “maximum permissible exposure” (MPE). The MPE limits are here.

Wi-Fi, Bluetooth, and most other unlicensed consumer devices are “categorically excluded” from RF evaluation because they operate at low enough power to be deemed intrinsically harmless. Certain fixed transmitters are also excluded, based on a combination of low enough power and high enough antenna mounting.

The current RF exposure levels date back to 1996. There are two sets of numbers: one for the general public, which the FCC intends to be conservative, and somewhat higher limits for those whose occupations entail working with and around radio transmitters, and who are presumed to understand the risks and know how to avoid them.

A large community of people believe the present RF standards – and particularly the “general population” standards – are far too lenient. Some fear that even FCC-compliant cell phones and other radio-based devices may be dangerous, especially to children. Others are concerned about exposure from antennas on buildings and towers.

Some of these concerns arise from theories that RF energy does more than just heat tissue. No one with scientific training seriously thinks radio waves can damage cells in the same ways that x-rays can. But other hypotheses abound – for example, that radio waves affect magnetic or electrical properties of molecules within cells. None of these hypotheses has been proven, at least to scientific standards. But that does not hinder their circulation on the Internet. Some observers assert other kinds of evidence – such as ADHD diagnoses growing in synchrony with cell phone adoption – to argue the two are connected. Every statistics student learns that correlation does not mean causation, but the human brain is wired to find these kinds of patterns, which can be very compelling.

The FCC’s recent action is unlikely to satisfy anyone on any side of the issue.

The opening section of the document, dubbed the “First Report and Order” (First R&O) adopts rules the FCC formally proposed ten years ago – a long time even by federal standards. There are no major policy shifts here, just a lot of fine-tuning.

Manufacturers are now permitted to use SAR testing even when it is not required. (Although more conservative and more expensive, SAR compliance can spare a manufacturer the need to design special housings that keep the user at a specified distance from the antenna.) The FCC has withdrawn its infamous OET Bulletin 65 Supplement C, long the bible on RF exposure testing. Instead, the FCC will now keep that information in its Knowledge DataBase (KDB) system, for easier updates. The First R&O clarifies that body-worn and implanted medical devices are subject to the RF exposure rules. Labeling and other requirements for use of the “occupational” limits are revised. There are adjustments to the rules for certain fixed transmitters. The FCC now classes the outer ear as an “extremity,” like hands and feet, a step that it concedes will have no discernible practical effect.

The “Further Notice of Proposed Rulemaking” (FNPRM) section of the document suggests several additional changes to the rules. These, too, are relatively small-scale adjustments that do not alter the basic structure of the FCC’s regulatory approach.

First are revisions of certain key definitions to better accord with reality. Second, the FCC proposes extensive changes to the methods for determining whether a device is categorically excluded from RF exposure testing. These do not seek to change the level of energy reaching the user. (That happens in the “Notice of Inquiry” section, described below). The aim here, rather, is to make the rules both simpler to apply and more consistent across different kinds of devices. Various of these proposals apply to individual devices and to multiple devices operating at the same location. Third, the FCC proposes to adjust the methods used for assessing compliance of “portable” devices, i.e., those used within eight inches of the body. Fourth, the FCC offers proposals for “mitigating” RF exposure, which involve such activities as labels, signs, barriers, job training, and enforcement. Many of these concern details of limiting and calculating occupational exposure. Finally, the FCC proposes an overall edit and clean-up of the RF exposure rules generally.

The specifics are too detailed for adequate summary here. We urge those interested to consult the NPRM, paragraphs 110 through 204.

The “Notice of Inquiry” (NOI) section is likely to be the most controversial. Here the FCC proposes to reopen the whole question of what numerical exposure limits are appropriate. It may have added fuel to the fire by stating the intent to “adequately protect the public without imposing an undue burden on industry.” No doubt some commenters will stress the importance of protecting the public regardless of the burden on industry. In addition to numerical limits, issues laid on the table in the NOI include:

  • the information that manufacturers and others should provide to consumers;
  • methods for reducing exposure (other than lowering the limits);
  • methods for evaluating exposure; and
  • the costs of imposing “precautionary” limits that are lower than current science can justify.

We hope the FCC is ready for a large volume of submissions. It has signaled, as plainly as it can, that “vague and unsupported assertions” will not carry much weight. But it will probably get a lot of those anyway.

Comments and replies will be due 90 and 150 days, respectively, after publication in the Federal Register, which will probably happen in late April or in May. Watch for updates.