The Federal Communications Commission (“FCC”) has resolved many of the issues that it has been considering since 2013 with respect to limits on exposure of human beings to radiofrequency (“RF”) energy. An important aspect of the decision is that existing exposure limits will not be tightened. However, the environmental rules dealing with RF exposure have been significantly re-written, with more uniform criteria for exemptions from environmental assessment, more flexibility in how to establish compliance, and more specificity in required mitigation techniques in exposure risk situations.

The issue of whether or not to tighten exposure limits has been controversial and has been the focus of increasing concern because of the proliferation and increased use of RF devices close to the human body, including cellphones, medical implants, wireless power chargers, and small cells for 5G mobile services. In declining to tighten limits, the FCC decided to follow the lead of the Food and Drug Administration (“FDA”) in finding that the weight of scientific evidence has not linked cellphones with health problems and does not dictate revisions on exposure limits for other devices. The FCC declined to adopt lower limits for environments where children are likely to be present. It noted that the extremely low limits advocated by some commenters would make it impossible to transmit any usable amount of energy and would thus essentially end the explosion of wireless radio technologies.

Although the limits themselves remain unchanged, the criteria for determine exemptions have been made more uniform across different types of equipment. There will be three categories of exemptions: (1) extremely low power devices that transmit at no more than 1 millwatt; (2) devices used within 0.5m to 40 cm of the human body, based on a table of values that takes into account power, distance, and frequency; and (3) other devices based on a general formula. In determining exemptions, account must be taken of multiple fixed devices operating in proximity to one another, based on the number of signals emitted and not the number of antennas. For example, if two 1 mW devices are intended to be used next to each other, they will be treated as a 2 mW device and will not be eligible for the 1 mW exemption. However, the fact that a mobile device may pass close to a fixed device will not be taken into account, since mobile device locations are impossible to predict, and a mobile device is not likely to remain near a fixed device for more than a short time.

Unlicensed devices operating under Part 15 of the FCC’s Rules will be subject to the new rules. All equipment currently being marketed in compliance with FCC standards and used as specified in user instructions may continue to be marketed and used; but manufacturers will have to evaluate their products under the new rules after an 18-month transition period.

The new rules limit situations where exposure levels at specific locations may be evaluated pursuant to exposure standards for trained workers to sites where access is realistically limited, and all workers (including contractors) who may come close to an antenna are all properly trained. Otherwise, the lower exposure levels for the general public will apply. Transient exposure above FCC limits may not exceed 30 minutes. The FCC is particularly concerned about rooftops that are supposedly not open to the general public but to where untrained persons have access (whether authorized or not). The more small cells that are installed on buildings, the higher the risk of exposure to harm. The new rules specify four levels of signage required for sites that pose exposure risks.

Compliance at sites with multiple users will be the responsibility of all users. The exemption from an environmental assessment (“EA”) relied on by many broadcasters if their emissions will result in exposure of less than 5% of the FCC limit for uncontrolled environments remains in the rules, but exemption from an EA will not relieve low level emitters from the obligation to cooperate in mitigating overall exposure at the site. It behooves site tenants to insist on language in their leases or licenses that requires the site owner to make all site users cooperate in keeping the overall site below FCC limits. Multi-user sites will have two years from the effective date of the new rules to determine whether their sites are in overall compliance or whether a deeper EA is needed.

In the coming months, FCC Bulletin OET56, with general questions and answers about RF exposure, will be withdrawn. Bulletin OET65, with more detailed requirements, will be revised.

Finally, the FCC has invited comments as to whether it should extend its regulation of RF emissions from the present range of 100 kHz to 100 GHz up to 3 THz (3,000 GHz). In light of current research and development efforts focusing on frequencies well above 100 GHz and into the THz range, it is likely that the FCC will adopt some standards to regulate emissions in these bands.

The effective date of the new rules and the deadline for comments on the proposed regulation of higher frequency bands will be based on when the FCC decision is published in the Federal Register. Watch for a posting when the dates are set.

Meanwhile, operators of transmission systems that have previously been considered “categorically exempt” from environmental assessment should analyze their installations under the new rules to make sure that they will continue to be in compliance.