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Review of Appendix BB, Revision 1 – General Steel Industries 

Robert Anigstein and John Mauro, SC&A
 

February 5, 2015
 
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LIST OF FINDINGS 

Finding 1 Neutron Dose Rates: Effective dose incompatible with OCAS-IG-001 

Finding 2 Beta Skin Dose—Beta doses to the skin of the betatron operator lower than SC&A’s 

Finding 3 No Dedicated Radiographic Facility in No. 6 Building Prior to 1955: Mode of triangular 

distribution needs to be increased since radiographers were in an unshielded location 

Finding 4 Maximum of Triangular Distribution of Photon Exposures for 1961 Should Be 12 R/y 

Finding 5 Combined Exposures to 226Ra and Betatron Operations During 1952–1962 

Finding 6 Beta Skin Dose to Layout Man Significantly Lower than Those Calculated by SC&A 

Finding 7 Uranium Inhalation From Metal Handling in 1966: Intake during first 6 months of 1966 is 

understated by a factor of 2. 

Finding 8 Ingestion Intakes Not Consistent with OCAS-TIB-009 

Finding 9 Ingestion Intakes During Residual Period Inconsistent with Operational Period 

Finding 10 External Exposure of Betatron Operator (New Finding): Effective dose incompatible with 

OCAS-IG-001 
RESOLUTION OF FINDINGS
 

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Finding 1: 	 DCAS agreed to revise the neutron dose calculations to use either ambient dose equivalent or 

deep dose equivalent conversions. 

Finding 2: 	 DCAS disagreed with SC&A beta skin dose to the betatron operator, intends to recalculate the 

using a new model. 

Finding 3: 	 DCAS intends to revise mode of triangular distribution to reflect radiographer’s photon dose at 

2 mR/h exclusion boundary during radiographic exposures during 1952–1955. 

Finding 4: DCAS intends to revise maximum of triangular distribution of photon exposures for 1961 to 

12 R/y. 

Finding 5: 	 DCAS disagreed with SC&A’s finding that radiographer using 226Ra could also have worked on 

betatron. 

Finding 6:	 DCAS disagreed with SC&A beta skin dose to the layout man, proposed revised doses based 

on a new model. 

Finding 7: 	 DCAS agreed to correct inhaled uranium intakes during first 6 months of 1966. 

Finding 8: 	 DCAS agreed to revise ingested uranium intakes during operational period, based on average 

annual airborne uranium concentrations during year of peak concentrations. 

Finding 9: 	 DCAS agreed to revise ingested uranium intakes during residual period, based on ingested 

intakes at end of operational period. 

Finding 10:	 DCAS has not yet responded to this new finding. 
 

 

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DETAILED DISCUSSION OF UNRESOLVED FINDINGS 

• Beta skin dose 

o Betatron operators—Finding 2 

•	 Unresolved differences between SC&A and NIOSH values 

Annual Doses to Skin of Betatron Operators from Beta Radiation (rads) 

Hands and forearms	 Other skin Year SC&A NIOSHa Ä SC&A NIOSHa Ä 

1952-1957 35.29 36.74 4% 4.32 3.87 -10% 

1958 30.20 31.31 4% 4.05 3.56 -12% 

1959-1960 28.10 29.07 3% 3.94 3.43 -13% 

1961 31.69 32.91 4% 4.13 3.65 -12% 

1962 24.06 24.76 3% 3.72 3.19 -14% 

1963 9.35 9.06 -3% 2.94 2.3 -22% 

1964 5.87 5.35 -9% 2.75 2.09 -24% 

1965 5.32 4.76 -10% 2.72 2.06 -24% 

1966b 2.38 2.09 -12% 1.35 1.01 -25% 

a Appendix BB, Rev. 1
 

b During contract period January 1–June 30
 

• NIOSH to revise beta skin dose to betatron operators using new model—results not yet available 
 

 

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o Layout man—Finding 6 

•	 Unresolved differences between SC&A and NIOSH values 

Annual Doses to Skin of Layout Man from Beta Rays Emitted by Irradiated Steel 

Skin on: SC&A 

Dose (rad/y) 

NIOSH 

2014a 2015b 

Hands and forearms 1.89 0.807 0.264 

Rest of body 

a Appendix BB, Rev. 1 

b NIOSH Response Paper 

1.14 0.463 0.147 
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•	 Radiographer may have been exposed to both 226Ra and betatron—Finding 5 

o	 Reason for finding: NIOSH assigned zero doses from neutrons and beta rays to plant workers during 

1952–1962 

o	 Technical basis: 

•	 GSI application for AEC byproduct materials license: "A maximum of 30% of each shift is used for 

actual exposure” (using 226Ra). 

•	 Radiographer could have worked with 226Ra sources and have still spent up to 70% of his shift in 

the Old Betatron Building radiographing uranium and steel 

•	 Interview with former GSI radiographer from Radium Era 

o	 Did both radium and betatron radiography— perhaps 50–60% of the time using the betatron, the 

remainder using radium 

o	 Only worked weekends: 40–90 shifts/y 

o	 Recorded dose 2.02 R/y—extrapolated dose to full-time radiographer: 9.1–20.5 R/y 

o	 Consistent with triangular distribution: 6.279–9.69–12 or 15 R/y during 1957–1961 

o Conclusion: Radiographer’s assumed exposure to both 226Ra and betatron is plausible and claimant 

favorable 
 

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o Result: 

•	 No change in photon dose 

Beta Skin Doses and Neutron Doses to Radiographers During Radium Era 

Year 

Beta skin dose (rads/y) 

Hands & 

forearms 

Rest of 

body 

Neutron H*(10) 

(rem/y) 

1952-1957 34.13 3.53 0.320 

1958 29.04 3.25 0.308 

1959-1960 26.95 3.14 0.303 

1961 30.54 3.33 0.311 

1962 22.90 2.93 0.293 

Note: Adjusted for 70% of work hours devoted to betatron radiography 
 

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•	 Assumed residual photon radiation from betatron after shutdown expressed as effective dose— 

incompatible with the dose conversion factors listed in OCAS-IG-001 (Finding 10—new) 

Estimated Maximum Weekly Air Kerma Dose to Betatron Operators 

Dose Coefficients for Maximum weekly Photon Energy PA geometry Breast air kerma (keV) (Gy/Gy) (mrad) 

30 0.0489 204 

40 0.181	 55 

50 0.328	 30 

60 0.439	 23 

70 0.511	 20 

80 0.545 18 

100 0.574 17 

150 0.6 17 

200 0.625 16 

300 0.663 15 

400 0.693 14 

500 0.717 14 

600 0.737 14 

800 0.767 13 

1,000 0.791 13 

2,000 0.863 12 

4,000 0.905 11 

6,000 0.911 11 

8,000 0.911 11 

10,000 0.911	 11 

Note: Based on an assumed dose to female breast (surrogate for film badge) of 10 mrem/week 

o Recommend using 204 mrad/week (10.2 rad/y) air kerma with maximum DCF for 30 keV photons