Department of Energy (DOE) Radiological Control Manual

Chapter 2 - Radiological Standards

Part 3 - Posting

Table of Contents (Articles 23x)

• 231 Posting Requirements
• 232 Posting Controlled Areas
• 233 Posting Radiological Buffer Areas
• 234 Posting Radiation Areas
• 235 Posting Contamination, High Contamination and Airborne Radioactivity Areas
• 236 Posting Radioactive Material Areas
• 237 Posting Underground Radioactive Material Areas

Article 231 - Posting Requirements

1. Radiological posting shall be used to alert personnel to the presence of radiation and radioactive materials and to aid them in minimizing exposures and preventing the spread of contamination. Boundaries used for radiological control purposes are depicted in Figure 2-1.

2. Signs shall contain the standard radiation symbol colored magenta or black on a yellow background. Lettering shall be either magenta or black. Magenta is the preferred color over black. Standardized signs, as described in the standardized core training, shall be used where practicable.

3. Signs shall be conspicuously posted, clearly worded, and, where appropriate, may include radiological control instructions. Radiological postings should be displayed only to signify actual or potential radiological conditions. Signs used for training should be clearly marked, such as "For Training Purposes Only."

4. Posted areas should be as small as practicable for efficiency.

5. Postings should be maintained in a legible condition and updated based upon the results of the most recent surveys.

6. If more than one radiological condition (such as contamination and high radiation) exists in the same area, each condition should be identified.

7. In areas of ongoing work activities, the dose rate and contamination level or range of each should be included on or in conjunction with each posting as applicable.

8. Entrance points to areas of ongoing work activities controlled for radiological purposes should state basic entry requirements, such as dosimetry, Radiological Work Permit (RWP) and respirator required.

9. Rope, tape, chain and similar barriers used to designate the boundaries of posted areas should be yellow and magenta in color.

10. Physical barriers should be placed so that they are clearly visible from all directions and at various elevations. They should not be easily walked over or under, except at identified access points. These barriers shall be set up such that they do not impede the intended use of emergency exits or evacuation routes.

11. Posting of doors should be such that the postings remain visible when doors are open or closed.

12. A radiological posting that signifies the presence of an intermittent radiological condition should include a statement specifying when the radiation is present, such as "CAUTION: RADIATION AREA WHEN RED LIGHT IS ON."

Article 232 - Posting Controlled Areas

1. Each access point to a Controlled Area shall be posted, identifying it as a Controlled Area, whenever radioactive materials or radiation fields which would require posting under Articles 234 or 235 (except for Fixed Contamination Areas) may be present in the area. Persons who enter only the Controlled Area without entering Radiation, Contamination, Airborne Radioactivity or Radiological Buffer Areas are not expected to receive more than 100 mrem in a year.

2. The contractor may select the type of sign used to avoid conflict with local security requirements. This selection shall be approved by the site senior executive.

Article 233 - Posting Radiological Buffer Areas

Radiological Buffer Areas shall be established within the Controlled Area to provide secondary boundaries to minimize the spread of contamination and to limit doses to general employees who have not been trained as radiological workers. It is not expected that Radiological Buffer Areas will be established around inactive or secured Contamination Areas. The need for Radiological Buffer Areas in conjunction with Radioactive Material Areas should be evaluated.

1. The size of the Radiological Buffer Area should be commensurate with the potential for the spread of contamination outside Contamination, High Contamination and Airborne Radioactivity Areas. At a minimum, the Radiological Buffer Area should include the area adjacent to any exit from and entrance to Contamination, High Contamination and Airborne Radioactivity Areas.

2. A Radiological Buffer Area is not required for High Contamination Areas or Airborne Radioactivity Areas that are completely within Contamination Areas.

3. A Radiological Buffer Area established to limit exposure to external radiation should surround Radiation, High Radiation and Very High Radiation Areas. The boundary for the Radiological Buffer Area should be established to limit radiation doses to general employees to less than 100 mrem per year. Radiological Buffer Areas need not be posted for external exposure control if other posted boundaries provide equivalent employee protection.

4. Posting of Radiological Buffer Areas shall be in accordance with Article 231 and shall contain the wording "CAUTION, RADIOLOGICAL BUFFER AREA."

Article 234 - Posting Radiation Areas

1. Areas shall be posted to alert personnel to the presence of external radiation in accordance with Table 2-3 and Article 231.

2. Dose rate measurements used to determine criteria for Radiation Areas should be made at a distance of 30 centimeters from the radiation source or from any surface through which the radiation penetrates. For Very High Radiation Areas, the measurement should be made at 100 cm.

3. Contact readings should be used to determine the need for posting Hot Spots. Measures taken to identify sources of elevated general area radiation levels while conducting routine radiation surveys should be sufficient to identify hot spot locations. Special surveys for the sole purpose of identifying hot spots should not be required.

4. A label marking the location of the Hot Spot should be placed on or as near the spot as practical. The provisions of Article 231.7 through 231.11 do not apply to the Hot Spot posting. Posting of Hot Spots is not required in areas with general area dose rates greater than 1 rem/hr.

5. The requirement for personnel dosimetry should be included on the sign.

6. The requirement for an RWP should be included either on or in conjunction with the posting.

7. Dose received in an hour may be used as the criterion for posting (Column 2 of Table 2-3). In this table, the unit "rad" is associated with dose rates that pose an immediate danger.

              Table 2-3  Criteria for Posting Radiation Areas




AREA          DOSE RATE CRITERIA        POSTING


Radiation     > 0.005 rem/hr            "CAUTION, RADIATION AREA"
Area          and < 0.1 rem/hr          "Personnel Dosimeter Required
              at 30 cm.                 for Entry"

High          > 0.1 rem/hr at           "DANGER, HIGH RADIATION AREA"
Radiation     30 cm and < 500           "Personnel Dosimeter,
Area          rad/hr at 100 cm.         Supplemental Dosimeter and RWP
                                        Required for Entry"*

Very High     > 500 rad/hr at           "GRAVE DANGER, VERY HIGH
Radiation     100 cm.                   RADIATION AREA"
Area                                    "SPECIAL CONTROLS REQUIRED FOR
                                        ENTRY"*

Hot Spot      5 times general           "CAUTION, HOT SPOT"
              area dose rate
              and > 0.1 rem/hr

* Access requirements may be deleted or modified if personnel
access is specifically prohibited.

Article 235 - Posting Contamination, High Contamination and Airborne Radioactivity Areas

1. Areas shall be posted to alert personnel to contamination in accordance with Table 2-4 and Article 231.

2. The requirement for an RWP should be included either on or in conjunction with each posting as applicable.

3. Derived Air Concentration (DAC) values for use with Table 2- 4 are found in 10 CFR 835.

4. Areas meeting the criteria for Fixed Contamination Areas specified in Table 2-4 and Article 222.3 do not have to be posted as Contamination or High Contamination Areas.

     Table 2-4  Criteria for Posting Contamination, High Contamination
                     and Airborne Radioactivity Areas


    AREA           CRITERIA                    POSTING

Contamination      Contamination levels        "CAUTION, CONTAMINATION
                   (dpm/100 cm2)               AREA"
                   > 1 time but
                   < 100 times
                   Table 2-2 values


High               Contamination levels        "DANGER, HIGH
Contamination      (dpm/100 cm2)               CONTAMINATION AREA"
                   > 100 times Table 2-2       "RWP Required for Entry"
                   values

Fixed              Removable contamination     "CAUTION, FIXED
Contamination      levels < Table 2-2          CONTAMINATION"
                   removable values and
                   total contamination
                   levels > Table 2-2
                   total values

Soil               Contaminated soil not       "CAUTION, SOIL
Contamination      releasable in               CONTAMINATION AREA"
                   accordance with
                   DOE 5400.5

Airborne           Concentrations              "CAUTION, AIRBORNE
Radioactivity      (æCi/cc) > 10% of        RADIOACTIVITY AREA"
                   any DAC value               "RWP Required for Entry"

Article 236 - Posting Radioactive Material Areas

1. Areas where radioactive materials are used, handled or stored should be posted "CAUTION, RADIOACTIVE MATERIAL." The posting shall meet the requirements in Article 231.

2. Radioactive Material Areas should be located within Controlled Areas.

3. Radioactive Material Areas are not required when the radioactive material in any one location:

4. Consists of ten or less sealed sources with half-lives less than 30 days or activities less than those specified in Table 1 of DOE N 5400.9 (Extended by DOE N 5400.10)
5. Is inside a Contamination, High Contamination, or Airborne Radioactivity Area.

• The definition of radioactive material and the requirements for labeling radioactive material are contained in Chapter 4. Return to Chapter 2, Part 3 Table of Contents

Article 237 - Posting Underground Radioactive Material Areas

1. Underground Radioactive Material Areas shall be established to indicate the presence of underground items that contain radioactive materials such as pipelines, radioactive cribs, covered ponds, covered ditches, catch tanks, inactive burial grounds, and sites of known, covered, unplanned releases (spills).

2. Underground Radioactive Material Areas shall be posted "UNDERGROUND RADIOACTIVE MATERIAL." Posting should include instructions or special warnings to workers such as "Consult With Radiological Control Organization Before Digging" or "Subsurface Contamination Exists." The posting shall meet the applicable requirements of Article 231.

3. Underground Radioactive Material Areas may be located outside Controlled Areas unless access is likely to result in individual doses greater than 100 mrem/year in a year from underground radioactive material.

4. Underground Radioactive Material Areas are exempt from the entry and exit requirements of Chapter 3 when access is not likely to result in individual doses greater than 100 mrem in a year. When access is likely to result in individual doses greater than 100 mrem in a year, entry requirements in Article 332.1 should be implemented.