RADIO FREQUENCY EMI/RFI Testing to

IEEE 299 Standards

Modern eavesdropping is more than standing around the corner listening to your conversation; sophisticated agents can monitor electronic communications from a great distance. Radio Frequency (RF) energy is generated by most standard equipment used in today’s workplace. Computer chips (microprocessors), monitors, printers, wires: all generate signals that can be monitored, recorded, and reconstructed. Computers are already an indispensable part of the modern world; as they become smaller, lighter, and more capable, the signals that they can generate are also receiving more scrutiny

CENTURION RF TESTS are performed in the field, with specialized equipment used to generate signals at specific frequencies and strengths, as well as equipment to observe and record signals. RF tests are generally performed for two reasons: to assess a barrier’s ability to attenuate RF energy; and to determine the ambient levels that exist in an area. All tests are performed to IEEE 299 Standards.

THE IMPORTANCE OF RF ENERGY

Energy that falls into the spectrum described above, or RF energy, has a number of special properties. For our purposes, the most important property is that the energy in an RF current can radiate from a conductor into free space as electromagnetic waves (radio waves). While this concept is the basis for directed wireless communication (your am\fm radio, wi-fi, cell phone, etc.), RF energy is also created in many other ways. RF energy is generated by most standard equipment used in today’s workplace. Computer chips (microprocessors), monitors, printers, wires: all generate signals that can be monitored, recorded, and reconstructed. Computers are already an indispensable part of the modern world; as they become smaller, lighter, and more capable, the signals that they can generate are also receiving more scrutiny.

INTERNAL AND EXTERNAL FREQUENCIES

The federal government of the United States has recognized the threat posed by RF energy emanating from equipment inside office space and work facilities. Modern eavesdroppers do more than stand around the corner listening to your conversation; sophisticated agents can monitor electronic communications from a great distance. For this reason, government facilities are required to protect themselves through a variety of technical security countermeasures designed to reduce or eliminate the ability of RF energy generated inside the facility to leak out and thus be exploited.

Assigning an STC rating to a barrier is a way to easily determine how much it is expected to dampen, or attenuate, sound waves. When a sound wave encounters a barrier, some of the energy from its vibrations transfers to that barrier. The properties of the barrier will determine how much energy is lost as the sound wave passes through it; this measurement, at a given frequency, is called the barrier’s transmission loss (TL) effectiveness. The higher the TL measurement, the more the barrier will reduce the sound’s power as the wave passes through it.

Since TL measurements are taken across a range of frequencies, it is sometimes difficult to compare two barriers. Sound transmission class (STC) ratings attempt to solve this problem by assigning a single integer value for acoustical performance.

To generally predict the ability of a constructed area to contain sound, a wide variety of barriers have been built and tested in laboratory settings. The STC values of these barriers are used by the construction industry to approximate the protection level that a space should achieve if the tested method of construction is implemented. Practically speaking, however, these values are only assumptions; from variances in the material creation process to differences in construction methods, field-built spaces rarely match laboratory test results. The only true way to measure an area’s attenuation properties is to perform field testing.