1. Regulations
  2. title 49
  3. chapter I
  4. part 173
  5. subpart I
  6. § 173.434

View all text of Subpart I [§ 173.401 - § 173.477]

§ 173.434 - Activity-mass relationships for uranium and natural thorium.

The table of activity-mass relationships for uranium and natural thorium are as follows:

Thorium and uranium enrichment 1(Wt% 235 U present) Specific activity TBq/gram Grams/Tbq Ci/gram Grams/Ci 0.45 (depleted)1.9 × 10−85.4 × 10 75.0 × 10−72.0 × 10 60.72 (natural)2.6 × 10−83.8 × 10 77.1 × 10−71.4 × 10 61.02.8 × 10−83.6 × 10 77.6 × 10−71.3 × 10 61.53.7 × 10−82.7 × 10 71.0 × 10−61.0 × 10 65.01.0 × 10−71.0 × 10 72.7 × 10−63.7 × 10 510.01.8 × 10−75.6 × 10 64.8 × 10−62.1 × 10 520.03.7 × 10−72.7 × 10 61.0 × 10−51.0 × 10 535.07.4 × 10−71.4 × 10 62.0 × 10−55.0 × 10 450.09.3 × 10−71.1 × 10 62.5 × 10−54.0 × 10 490.02.1 × 10−64.7 × 10 55.8 × 10−51.7 × 10 493.02.6 × 10−63.9 × 10 57.0 × 10−51.4 × 10 495.03.4 × 10−63.0 × 10 59.1 × 10−51.1 × 10 4Natural thorium8.1 × 10−91.2 × 10 82.2 × 10−74.6 × 10 6

1 The figures for uranium include representative values for the activity of uranium-234 which is concentrated during the enrichment process. The activity for thorium includes the equilibrium concentration of thorium-228.

[Amdt. 173-244, 60 FR 50307, Sept. 28, 1995, as amended by 63 FR 52849, Oct. 1, 1998]

AUTHORITY: 49 U.S.C. 5101-5128, 44701; 49 CFR 1.81, 1.96 and 1.97.

CITE AS: 49 CFR 173.434