ANSI HPS N43.2-2001 pdf download Radiation Safety for X-ray Diffraction and Fluorescence Analysis Equipment
6.1.1.3 System barrier. Each radiation area shall be surrounded by a system barrier with sufficient inherent shielding so that the dose equivalent received by individuals in the surrounding controlled area does not exceed 0.05 mSv (5 mrem) in any one hour at 30 cm (1 foot) from the source or any surface that the radiation penetrates.
6.1.1.4 Caution sign. Each radiation area shall be conspicuously posted with a sign or signs bearing the trefoil radiation symbol and the words: CAUTION: RADIATION AREA The standard colors for signs are a magenta trefoil and wording on a yellow background. Additional wording may be included such as “When the Equipment Is Energized”.
6.1.1.5 Supervision. Each radiation area shall be under the general supervision of a Radiation Safety Officer and under continuous supervision by an operator during operation. Note that continuous supervision may not require continuous personnel presence, but control over access to the radiation area is to be maintained. For example, continuous supervision may involve personnel presence, door locks, entry monitors, or other engineered solutions.
6.1.2 Controlled Area
6.1.2.1 Designation of a controlled area. Any area in which the dose equivalent received by individuals may exceed 1 mSv (100 mrem) in any year, but does not exceed the levels that would require it to be designated a radiation area (see 6.1.1.1), shall be designated a controlled area. Access to controlled areas is managed in order to protect personnel from occupational radiation exposure.
6.1.2.2 Installation enclosure. Each controlled area shall be visibly separated from adjacent uncontrolled areas by an installation enclosure so that the dose equivalent received by individuals in the uncontrolled areas does not exceed 1 mSv (100 mrem) in any year. This may be accomplished by the use of shielding, distance, or other means.
6.1.2.3 Identifying sign. Each controlled area shall be identified by an appropriate and easily recognizable warning sign posted at each entrance. For example, a black and yellow sign with the following words could be used: