Page 1 of 2

National Institute for Occupational Safety and Health 

Division of Compensation Analysis and Support 

DEPARTMENT OF HEALTH & HUMAN SERVICES 

This working document was prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions with the

ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or ABRWH (or their technical

support and review contractors) positions unless specifically marked as such. This document represents preliminary positions taken on technical issues prepared

by NIOSH or its contractor. NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC 

§552a and has been cleared for distribution. 

Memorandum

To: URAWE Working Group 

From: LaVon Rutherford, DCAS Health Physicist 

 Mutty Sharfi, ORAU Team Health Physicist

Subject: Response to SC&A’s Comments on SEC Evaluation Report for SEC-00217 

Date: May 24, 2016 

The following are responses to SC&A’s July 2016 report on the Special Exposure Cohort Evaluation 

Report (ER) for SEC-00217, Westinghouse Electric Corporation (New Jersey), which was issued in 

April 14, 2015. 

Observation 1. Mode 2 ingestion exposures based on OCAS-TIB-009 should be adjusted for the 

duration of the work-day (i.e., 8, 8.8 or 9.6 hr) based on the dates which the exposures occurred.

The assumption was made that during the residual period the occupancy time was 8 hours per work-day. 

However, SC&A is correct that to be consistent with Battelle-6000, the occupancy time should be as 

follows: 

 1950 – 48 hours (9.6 hr/day) 

 1951–1955 – 44 hours (8.8 hr/day) 

 After 1955 – 40 hours (8 hr/day) 

Therefore, the occupancy times will be updated to reflect the recommendations in Battelle-6000. 

Observation 2. The deposition time used in the Model DR (Spreadsheet 2015) is not consistent 

with that proposed on p. 37 of NIOSH 2015.

NIOSH agrees that there is an inconsistency with the 5 days reported in the ER and the application of 30 

days in the calculations. Since the 3rd operational period only lasted 5 days, NIOSH agrees that the 

residual surface contamination levels for the 3rd residual period should not be based on 30 days. NIOSH 

will update the calculations for the 3rd residual period to 5 days. 

Finding 1. The procedure for calculating air concentrations during the 1st residual period is not 

consistent with the guidance provided in ORAUT-OTIB-0070.

NIOSH agrees that the recommended approach for a residual period with a known end concentration is 

to estimate the operational air concentration using Battelle-6000 or ORAUT-OTIB-0070. NIOSH also 

agrees with SC&A that the interpretation of that is unclear. 

We understand SC&A’s concern that backwards extrapolation using the default removal rate of 

0.000067/day provided in OTIB -0070 is not necessarily claimant favorable. However, given that 
Page 2 of 2

This working document was prepared by NIOSH’s Division of Compensation Analysis and Support (DCAS) or its contractor for use in discussions with the

ABRWH or its Working Groups or Subcommittees. Draft, preliminary, interim, and White Paper documents are not final NIOSH or ABRWH (or their technical

support and review contractors) positions unless specifically marked as such. This document represents preliminary positions taken on technical issues prepared

by NIOSH or its contractor. NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC 

§552a and has been cleared for distribution. 

SC&A’s independent analysis of the available data using TBD-6000 demonstrated that NIOSH’s 

backwards extrapolation was indeed claimant favorable (85 dpm/m3 vs 69 dpm/m3), we believe that the 

air concentration value calculated by NIOSH should be used. 

Finding 2. The guidance provided in OTIB-0070 (Section 3.6) for calculating doses during the 

residual period refers to OCAS-TIB-009 (NIOSH 2004). This guidance should be revised, since the 

OCAS-TIB-009 approach cannot be used to calculate ingestion intakes from transfer of surface 

contamination to the hands and then to the mouth. Use of the procedure in TIB-009 understates 

this source of ingestion. The calculations in the SEC-00217 ER for the 1st residual period should 

be modified accordingly.

NIOSH agrees that they have committed to limit the scope of OCAS-TIB-009 to operational years. 

Therefore, NIOSH agrees to modify the ingestion intakes to be equal to the non-radiation production 

area workers ingestion intakes from the prior operational period for the first year and then apply source 

term depletion rate for all subsequent years. Given that during the residual period there is no on-going 

covered operations, the ingestion rate for the first year of the residual should not exceed the ingestion 

rate of a worker that works in the production area, but does not handle the material directly (i.e. source 

term for the worker is indirect exposure or exposure to contamination). This change is applicable to all 

three residual periods. 

This can be done during the 1st residual period using the approach suggested by SC&A or by taking the 

85 dpm/m3calculated for the start of the residual period and using the equation for resuspension of 

surface contamination from OTIB-70 calculate back to determine the surface contamination. Then take 

the surface contamination and divide by the deposition velocity and deposition time to get the 

operational air concentration. The operational air concentration can be multiplied by .2 for the initial 

ingestion rate. 

LaVon Rutherford 

DCAS SEC Health Physics Team Leader