Table 2-2 Summary of Surface Contamination Values [see 835 Appendix D]

DOE-STD-1098-99

Radiological Control

Radiological Standards

June 2004

Table 2-2 Summary of Surface Contamination Values [see 835 Appendix D]

TOTAL (FIXED +

REMOVABLE

REMOVABLE)

(dpm/100 cm2)

RADIONUCLIDE

(See Note 1)

(See Note 2)

(See Note 3)

U-natural, U-235, U-238, and associated decay products

1,000 alpha

5,000 alpha

Transuranics, Ra-226, Ra-228, Th-230, Th-228, Pa-231, Ac-227,

I-125, I-129

500

Th-nat, Th-232, Sr-906, Ra-223, Ra-224,

U-232, I-126, I-131, I-133

200

1,000

Beta-gamma emitters (nuclides with decay modes other than

alpha emission or spontaneous fission) except Sr-90 and others

1,000 beta-

noted above. Includes mixed fission products containing Sr-907.

gamma

5,000 beta-gamma

Tritium and tritiated compounds

10,000

Notes:

Except as noted in Footnote 5 below, the values in this Table apply to radioactive contamination deposited on, but not incorporated into the

interior of, the contaminated item. Where contamination by both alpha- and beta-gamma-emitting nuclides exists, the limits established for the

alpha- and beta-gamma-emitting nuclides apply independently [see 835 App. D, note 1].

The amount of removable radioactive material per 100 cm2 of surface area should be determined by swiping the area with dry filter or soft

absorbent paper while applying moderate pressure and then assessing the amount of radioactive material on the swipe with an appropriate

instrument of known efficiency (Note: The use of dry material may not be appropriate for tritium.). For objects with a surface area less than 100

cm2, the entire surface should be swiped, and the activity per unit area should be based on the actual surface area. It is not necessary to use

swiping techniques to measure removable contamination levels if direct scan surveys indicate that the total residual contamination levels are

below the values for removable contamination [see 835 App. D, note 4].

The levels may be averaged over 1 square meter provided the maximum activity in any area of 100 cm2 is less than three times the values in

Table 2-2 [see 835 App. D, note 3].

This category of radionuclides includes mixed fission products, including the Sr-90 which is present in them It does not apply to Sr-90 that has

been separated from the other fission products or mixtures where the Sr-90 has been enriched [see 835 App. D, note 5].

Tritium contamination may diffuse into the volume or matrix of materials. Evaluation of surface contamination shall consider the extent to

which such contamination may migrate to the surface in order to ensure the surface radioactivity value provided in this Table is not exceeded.

Once this contamination migrates to the surface, it may be removable, not fixed; therefore, a "Total" value does not apply [see 835 App. D, note

6].

These values should be applied to total Sr-90/Y-90 activity resulting from processes involving the separation or purification of Sr-90.

These values should be applied to total Sr-90/Y-90 activity resulting from the presence of Sr-90 in mixed fission products.

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