SCO
Surface Contaminated Object (SCO) means a solid object which is not itself radioactive but which has radioactive material distributed on its surface. SCO exists in two phases:
(1) SCO-I: A solid object on which:
(i) The non-fixed contamination on the accessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 4 Bq/cm
2 (10−4 microcurie/cm
2) for beta and gamma and low toxicity alpha emitters, or 0.4 Bq/cm
2 (10−5 microcurie/cm
2) for all other alpha emitters;
(ii) The fixed contamination on the accessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 4 × 10
4 Bq/cm
2 (1.0 microcurie/cm
2) for beta and gamma and low toxicity alpha emitters, or 4 × 10
3 Bq/cm
2 (0.1 microcurie/cm
2) for all other alpha emitters; and
(iii) The non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 4 × 10
4 Bq/cm
2 (1 microcurie/cm
2) for beta and gamma and low toxicity alpha emitters, or 4 × 10
3 Bq/cm
2 (0.1 microcurie/cm
2) for all other alpha emitters.
(2) SCO-II: A solid object on which the limits for SCO-I are exceeded and on which:
(i) The non-fixed contamination on the accessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 400 Bq/cm
2 (10−2 microcurie/cm
2) for beta and gamma and low toxicity alpha emitters, or 40 Bq/cm
2 (10−3 microcurie/cm
2) for all other alpha emitters;
(ii) The fixed contamination on the accessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 8 × 10
5 Bq/cm
2 (20 microcurie/cm
2) for beta and gamma and low toxicity alpha emitters, or 8 × 10
4 Bq/cm
2 (2 microcuries/cm
2) for all other alpha emitters; and
(iii) The non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm
2 (or the area of the surface if less than 300 cm
2) does not exceed 8 × 10
5 Bq/cm
2 (20 microcuries/cm
2) for beta and gamma and low toxicity alpha emitters, or 8 × 10
4 Bq/cm
2 (2 microcuries/cm
2) for all other alpha emitters.