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Surface Contaminated Objects (SCO)

Surface contaminated object (SCO) means a solid object which is not itself radioactive but which has radioactive material distributed on its surface.

SCO is classified in one of three groups:

  1. SCO-I: A solid object on which:
    1. the non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 0.4 Bq/cm2 for all other alpha emitters; and
    2. the fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 4 × 103 Bq/cm2 for all other alpha emitters; and
    3. the non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 4 × 103 Bq/cm2 for all other alpha emitters;
  2. SCO-II: A solid object on which either the fixed or non-fixed contamination on the surface exceeds the applicable limits specified for SCO-I in (a) above and on which:
    1. the non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 400 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 40 Bq/cm2 for all other alpha emitters; and
    2. the fixed contamination on the accessible surface, averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 8 × 104 Bq/cm2 for all other alpha emitters; and
    3. the non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 8 × 104 Bq/cm2 for all other alpha emitters.
  3. SCO-III: A large solid object which, because of its size, cannot be transported in a type of package described in these Regulations and for which:
    1. all openings are sealed to prevent release of radioactive material during conditions defined in 4.1.9.2.4 e) (ADR, RID, ADN) or 4.1.9.2.4.5 (IMDG Code);
    2. the inside of the object is as dry as practicable;
    3. the non-fixed contamination on the external surfaces does not exceed the limits specified in 4.1.9.1.2; and
    4. the non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm2 does not exceed 8 × 105 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 8 × 104 Bq/cm2 for all other alpha emitters.