Non-Ionizing Radiation

DOE-HDBK-1092-2004

9.13 NON-IONIZING RADIATION

9.13.1 ELECTROMAGNETIC RADIATION

Human exposure to electromagnetic (EM) radiation at certain power-density levels can be

hazardous. The hazards are generally regarded to be associated with the heating of biological

tissue, which occurs when EM radiation is absorbed by a body. This heating is essentially

similar to the cooking process in a microwave oven. Use caution where EM sources are being

used with the shielding altered or removed.

When working with EM radiation, it is recommended that the emitted radiation levels be

estimated by equations and measured by radiation hazard monitors.

EM radiation-safe levels have been established by the Institute of Electrical and Electronics

Engineers and are documented in the IEEE standard - C95.1-1999. Also, see Section 10.8.4.

Exposure to hazardous levels of EM radiation can be lessened by maintaining as much distance

as possible from the source. Power density is reduced by a factor the square of the distance

from the source (e.g., a factor of 4 for 2 times the distance).

9.13.2 ELECTROMAGNETIC RADIATION THREAT TO ELECTROEXPLOSIVE

DEVICES

Designers of enclosed electrical/electronic equipment must consider the possible effects on

nearby EED of electromagnetic radiation (EMR); i.e., radio frequency (RF) energy, emitted by

that equipment.

Energy induced into an EED by the electromagnetic field resulting from such emissions may be

adequate to cause the device to initiate detonation.

Factors which should be taken into account in assessing concerns for possible EMR emissions

are:

1. Wiring, shielding, and sensitivity

2. Proximity

3. Frequency of the emissions causing coupling of electrical energy

4. Power density

5. Type of emission modulation

Possible measures to mitigate the threat of EMR emissions include:

1. Enclosure and signal line shielding and grounding to prevent leakage of EMR from the

equipment.

2. Designed-in physical separation or barrier that would ensure that the power density of the

electromagnetic field is inadequate to cause detonation of an EED at the closest possible

distance to the emission source within the equipment.

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