Ground-penetrating radar (GPR) provides images of the subsurface by using the electromagnetic spectrum (EMS) in the microwave range between 10 MHz and 2.6 GHz. These signals are transmitted through the ground and reflect off of subsurface structures based on their electrical permittivity. A receiving antenna records variations in the return signals, which the GPR device uses to generate images that generally indicate changes in electrical properties.
Most countries regulate devices that emit EM radiation, largely due to their potential for interfering with other devices on the same frequency. However, the specific laws and their level of enforcement vary greatly by jurisdiction. The manufacturers and operators of GPR need to stay abreast of these regulations, which change regularly.
Why Is Regulation Needed for Ground-Penetrating Radar?
Governments throughout the world have closely managed and regulated the use of the EMS for decades. The primary reason for all these rules is that powerful EM broadcasters like radio and TV stations could render each other’s broadcasts useless if they operated on the same frequency, especially if they’re in close proximity. International coordination is needed because two such stations can be on opposite sides of a national border, even when they’re near each other.
Furthermore, governments routinely license the EMS, meaning they sell the rights to use a particular frequency range within a certain geographic area. Once someone pays the license fee, they essentially own that frequency band within their designated area. These slices typically cover only a few kHz or MHz each, but they can cover the entire EMS from 100 kHz to 100 MHz. These licenses are extremely lucrative for governments, as some of the frequency bands used by cell phones have sold for over a billion dollars. Governments, therefore, have a strong financial incentive to ensure the EMS remains free of interference.
What Bodies Are Responsible for GPR Regulation?
The multinational nature of EM regulation makes its organizational and administrative structure complex. For example, the International Telecommunications Union (ITU) is the international coordinating body for EM spectrum regulation, although spectrum managers in the individual countries are the primary regulators.
The Federal Communications Commission (FCC) regulates public use of the EMS in the United States, while the National Telecommunication and Information Administration (NTIA) manages the U.S. government’s use of the EMS. The FCC generally requires an approved organization to test devices that emit EM radiation. The FCC then reviews the results and issues a unique identifier if it approves the device. This identifier must be displayed on the product and its manuals, along with FCC warnings regarding its proper use. All EM devices approved for use in the U.S. and Canada are listed on government web sites.
Industry Canada (IC) performs a role similar to the FCC in Canada, and the European Telecommunications Standards Institute (ETSI) is an independent organization that manages telecommunications standards in Europe. Manufacturers must indicate the specific ETSI standards that a device complies with and provide the documentation needed to verify these claims.
Tips on GPR Compliance
A GPR device must comply with its country’s regulations before it can be legally sold or operated. Furthermore, the penalties for violating these regulations can be severe. These regulations have applied to GPR for the last 10 to 20 years in most countries, which generally follow FCC or ETSI standards. However, jurisdictions typically have variations on these standards, which can change at any time.
Seemly minor changes in technology can pose major challenges in regulating these devices. For example, a revised ETSI standard with a series of minor technical changes in GPR devices have been awaiting adoption for the past four years, keeping these devices in regulatory limbo in Europe.
GPR users need to adhere to the current regulations, with the understanding that these rules are currently very much in flux. It’s particularly important that they only buy certified equipment to avoid causing significant interference on a heavily used frequency. Such an incident could prompt a review of the current standards, resulting in greater restrictions on GPR operations.
The most convenient way to do this is to locate the required sticker on the GPR device or search the applicable website for the manufacturer’s product. You can also request the FCC or IC identification number from the vendor. In Europe, you would ask for the ETSI declaration of conformity. Take your business elsewhere if the GPR doesn’t comply with your country’s EMS regulations.
Ground-Penetrating Radar Services
SoftDig®, is a full-service, Subsurface Utility Engineering (SUE) firm. Our SoftDig system was designed in 1959 by one of our founders and has been used to locate underground utility lines for many years in North America, Europe and Australia. We also provide a complete range of utility locating services throughout much of the United States that uses GPR.