Incidental X-Ray Devices - hdbk110997

DOE-HDBK-1109-97

Radiological Safety Training for Radiation-Producing (X-Ray) Devices

Student's Guide

televisions, electron microscopes, high-voltage electron guns, electron beam welding

machines, electrostatic separators, and Jennings switches.

An intentional X-ray device is designed to generate an X-ray beam for a particular use.

Examples include X-ray diffraction and fluorescence analysis systems, flash X-ray

systems, medical X-ray machines, and industrial cabinet and noncabinet X-ray

equipment. Intentional X-ray devices are further divided into two subcategories:

analytical and industrial.

ANSI has issued two standards that provide radiation safety guidelines for X-ray systems.

ANSI N43.2 applies to non-medical X-ray systems and ANSI N43.3 applies to X-ray

diffraction and fluorescence systems.

INCIDENTAL X-RAY DEVICES

Exempt Shielded Systems.

Exempt shielded systems are defined in the ANSI Standard N43.3. Electron

microscopes and other systems that are exempt shielded are inherently safe, and

require review only on purchase or modification. The exposure rate during any

phase of operation of these devices at the maximum-rated continuous beam

current for the maximum-rated accelerating potential should not exceed 0.5

mrem/hour at 2 inches (5 cm) from any accessible external surface.

(Add facility-specific examples.)

ii.

Other Devices.

At a research laboratory, many devices produce incidental X-rays. Any device

that combines high voltage and a vacuum could, in principle, produce X-rays. For

example, a television or computer monitor generates incidental X-rays, but in

modern designs the intensity is small, much less than 0.5 mrem/hour.