National Institute for Occupational Safety and Health

Sandia National Laboratories - Albuquerque

SEC-00188 Addendum 2

Charles Nelson, MS

Health Physicist

Sandia National Laboratory Work Group

March 3, 2022
Summary of SEC-00188 Petition History

 Petition qualified (83.13) for evaluation: October 21, 2011

 Petitioner proposed class definition:

• All Security Inspectors, Security Clerks, Firemen, Non-regular Recurrent Security 

Inspectors, Security Officers, Security Police Officers I, Security Police Officers II, 

Security Police Officers III, and Central Alarm System Operators that worked in 

any area at SNL-A for the period from January 1, 1963, through May 21, 2011

 NIOSH proposed the following class to be added to the SEC on February 21, 2012:

• All personnel that worked in any area at Sandia National Laboratories in 

Albuquerque, New Mexico for the period from January 1, 1949, through 

December 31, 1994
Basis for 1949-1994 SEC Class

 Insufficient monitoring data and information to reconstruct internal dose from 

January 1, 1949 through December 31, 1994:

• Lack of internal monitoring program documentation

• Lack of internal monitoring data

• Lack of process information 

 The Evaluation Report published February 21, 2012, concluded that external doses, 

including medical X-rays performed onsite as a condition of employment can be 

reconstructed for the duration of the evaluation period January 1, 1949, through May 

21, 2011

• Continued evaluation since publication of the 2012 report has not identified any 

information which would contradict this conclusion regarding external dose
Summary of SEC-00188 Addendum (1995-1996)

 NIOSH proposed the following class to be added to the SEC on July 26, 2018:

• All personnel that worked in any area at Sandia National Laboratories in 

Albuquerque, New Mexico for the period from January 1, 1995, through 

December 31, 1996
Basis for 1995 – 1996 SEC Class

 Internal monitoring program concerns

 Air monitoring data deficiencies

• Uncertainties and concerns associated with the transitional and 

developmental nature of SNL-A’s internal monitoring program

• The site was making several improvements in the internal monitoring 

program including an increase in the use of personal and area air monitoring

• The program seemed to be lacking formalization in that NIOSH did not find 

adequate evidence that some key implementing procedures were fully in 

place until 1996 & 1997
SEC-00188 Addendum 2 (1997 – 2011)

The focus of Addendum 2 was determining Internal Dose Reconstruction feasibility:

 Determine suitability of monitoring program and documentation 

 Determine monitoring data sufficiency

 Address security guards’ monitoring concerns
Data Sources Reviewed for SEC-00188 Addendum 2

 21 Interviews with 17 people

 1 Site data capture effort/trip since last SEC designation

 4 Written data capture requests

 Over 900 relevant documents captured and reviewed since SEC-0188 was issued in 

2012 (NIOSH has over 5,500 total documents in its database pertaining to SNL-A):

• Internal procedures and memos

• 10 CFR pt. 835 Compliance and self-assessment reports/memos

• Facility and process information

• Radiation Work Permits

• Incident reports

• Air monitoring data

• Internal and external radiological program audits and assessments
Data Sources Reviewed, cont.

 Extracts from SNL-A’s “WebDose” database which the site uses for bioassay

monitoring and as a reporting tool

 Internal/external monitoring records

 Breathing Zone (BZ) monitoring and air sample records

 Derived Air Concentration (DAC)-hour tracking
Available Internal Monitoring 

WebDose Urine Bioassay

Year Non-H3 Sample Results Persons Sampled (Non-H3) H3 Sample Results Persons Sampled (H3) 

1997 111 45 238 100

1998 144 59 375 126

1999 187 67 440 83

2000 119 46 375 50

2001 90 39 426 58

2002 111 46 575 78

2003 160 55 679 78

2004 158 51 677 70

2005 172 60 647 69

2006 128 40 500 51

2007 115 35 438 47

2008 101 33 424 40

2009 121 42 435 40

2010 138 48 446 39

2011 165 47 534 54

Total 2020 317 7209 362
Available Internal Monitoring, cont.

WebDose WB/Thyroid Count Data

Year Measurements Persons Monitored

1997 59 54

1998 66 55

1999 58 52

2000 265 40

2001 73 33

2002 54 43

2003 102 61

2004 60 46

2005 65 58

2006 61 54

2007 45 42

2008 29 28

2009 48 40

2010 40 39

2011 90 50

Total 1115 207
Internal Dose Monitoring Program Overview

 SNL-A shifted the emphasis of the Internal Monitoring Program from reliance on 

bioassay to the use of breathing zone sampling as a primary method of monitoring

 It was SNL-A’s position that no individual was likely to receive an internal exposure 

of 100 mrem

• This is stated both in the Internal Technical Basis documentation and in external 

assessments performed in 1996 and 1999

 SNL-A used a confirmatory bioassay monitoring program

• BZ monitoring was the primary method of internal dose monitoring

• The site did not rely solely on bioassay monitoring to assess potential exposure to SNL-A

personnel

• Change of emphasis from internal dosimetry to internal radiation protection and reliance 

on other types of monitoring to be indicative of the need for bioassay
Internal Dose Monitoring Program Evidence of Field 

Implementation

 February 3, 1998, summary of Radiological and Mixed Waste Management Facility 

(RMWMF) safety committee discussion regarding routine bioassay 

• “The RCTs at the RMWMF are on routine bioassay. If a trend developed indicating 

internal doses, RMWMF personnel would undoubtably [sic] be asked to submit 

special bioassay samples to determine the scope of the problem.”

• “If trends developed indicating elevated air concentrations or increased surface 

contamination levels, special bioassay samples would be requested from 

appropriate facility personnel.”

• “Job specific RWPs require bioassay, as appropriate, for those workers involved 

with tasks where significant levels of radionuclides, or certain specific 

radionuclides (e.g., 3H) are handled.”
Internal Dose Monitoring Program Evidence of Field 

Implementation, cont.

 May 30, 2001, memo documenting the routine bioassay program for RCTs at TA-V

• “The current schedule calls for annual whole body counting and semi-annual 

urinalysis samples for U, Th, Am, and Pu.”

• “The SNL bioassay program is confirmatory in nature. The bioassay program 

confirms the results and effectiveness of contamination control and other 

personnel protection activities.”

• “Since Radiological Control technicians (RCTs) must be present in all work activities 

where the possibility of meaningful intakes is credible, their bioassay serves as a 

good proxy indicator for potentially exposed line personnel,...”
Internal Dose Monitoring Program Evidence of Field 

Implementation, cont. 

 Captured RWPs and work planning documents were reviewed for indication of 

airborne radioactive material, respiratory protection, personal/area air monitoring 

requirements, and bioassay

 Indications of surface and airborne radioactive materials were noted as was the use 

of respiratory protection, personal and/or area air monitoring requirements, and 

bioassay

 Review of RWPs supports Rad Program adherence to contemporary procedures
Analysis of Breathing Zone (BZ) Data

In order to evaluate the internal dose associated with BZ filters, the following steps 

were performed

 Intake quantity associated with each BZ filter was determined

 Committed Dose associated with the intake quantities were calculated and based 

on the stochastic Annual Limit on Intake (ALI) for the limiting nuclide for the 

analysis type (i.e., gross alpha, beta/gamma, tritium)

 Committed Dose analyzed to determine the distribution of the data grouped by 

event. An event is defined two ways: a radiological work task at a given location on 

a given day, and all radiological work on a given day
Results of Analysis of Breathing Zone (BZ) Data

 The median quantity of radioactive material available for internal uptake to individuals 

located alongside personnel performing high risk radiological work would correspond to an 

internal dose of 0.5 mrem per work event or per workday 

 This dose quantity assumes that the individual is present within the work area and is not 

wearing respiratory protection (note respiratory protection is typically used) 

• The fact that such individuals would be afforded a significant reduction in intake 

potential by the separation between the actual work and the area that can be occupied 

without the same level of radiological controls is not considered in this assessment

 It is not likely that an individual would be able to receive 100 mrem per year of internal 

exposure under these conditions (i.e., an individual would have to be present for 200 

events, based on the median dose, to receive an exposure in excess of 100 mrem in a year
Assigned Committed Dose (rem); WebDose: 1997 – 2011

Year H3 BZ Urine Thyroid Total

1997 0 0 0 0 0

1998 0 0.010 0 0 0.010

1999 0 0 0 0 0

2000 0 0 0 0.005* 0.005

2001 0 0 0 0 0

2002 0 0 0 0 0

2003 0 0.012* 0 0 0.012

2004 0 0 0 0 0

2005 0 0 0 0 0

2006 0 0 0 0 0

2007 0 0 0 0 0

2008 0 0 0 0 0

2009 0 0 0.023 0 0.023

2010 0 0.004 0.019 0 0.023

2011 0.004 0 0 0 0.004

Total 0.004 0.026 0.042 0.005 0.077

* Indicates dose was distributed among multiple individuals.
Feasibility of Dose Reconstruction 1/1/97 – 5/21/11

 Based on its review of radioactive material use at Sandia-Albuquerque and the 

associated radiation protection programs, NIOSH has concluded that intakes for 

unmonitored workers with access to controlled areas were unlikely to have resulted 

in committed effective dose equivalents (CEDE) in excess of 0.1 rem per year 

 This conclusion is not wholly based upon the implementation of 10 C.F.R. §

835.402, but rather on a review of exposure monitoring records for individuals 

involved in radiological activities with the highest risks at the site during the period 

under evaluation
Feasibility of Dose Reconstruction 1/1/97 – 5/21/11, cont.

 The total assigned internal dose (CEDE) for all employees combined for the 15-year period 

from 1997 through 2011 is 77 mrem 

 A review of available breathing zone bioassay data indicates that the median quantity of 

radioactive material available for internal uptake to individuals located alongside personnel 

performing high-risk radiological work would correspond to an internal dose of 0.5 mrem 

per work event or per workday 

• Assumes the individual is present within the work area alongside of worker

• Assumes no respiratory protection/breathing same concentration of air as worker

 In either case, consistent with the recorded internal dose of 77 mrem above, it is not likely 

that an individual would be able to receive 100 mrem per year of internal exposure under 

these conditions

• An individual would have to be present for 200 events, based on the median dose, to 

receive an exposure in excess of 100 mrem in a year
Feasibility of Dose Reconstruction 1/1/97 – 5/21/11, cont.

 As previously identified in SEC-00188 Evaluation Report in 2012, NIOSH finds it is 

feasible to reconstruct occupational medical doses and principal sources of 

external radiation exposure including beta, gamma, and neutron radiation for 

Sandia National Lab-Albuquerque employees with sufficient accuracy

 As previously identified in SEC-00188 Evaluation Report, the principal sources of 

internal radiation for members of the proposed class included exposures to 

plutonium, tritium, uranium, americium, and fission and activation products 

• Potential exposure pathways could have involved the handling of these 

radionuclides during waste-burial operations or exposure to surface or air 

contamination associated with reactor and/or accelerator work

• Considering the potential exposure scenarios, program policies, procedures, and 

monitoring data availability, NIOSH finds it able to estimate these internal doses 

with sufficient accuracy for the period
Feasibility of Dose Reconstruction 1/1/97 – 5/21/11, cont.

 Based upon its analysis of the available resources, NIOSH found no part of the class 

under evaluation for which it cannot estimate radiation doses with sufficient 

accuracy
Feasibility Findings

SEC-00188, Addendum 2

(January 1, 1997 – May 21, 2011)

Source of Exposure Dose Reconstruction is Feasible

Internal – All Radionuclides Yes

External – Beta/Gamma Yes

External – Neutron Yes

External – Occupational Medical X-Ray Yes
Recommendation

Class Feasibility Health Endangerment

January 1, 1997 – May 21, 2011 Yes N/A
Updates to BZ Monitoring Dataset

 Additional Data received from the site on July 2, 2019, successfully augmenting 

the previously available BZ data

Year Prior Additional Total Year Prior Additional Total Year Prior Additional Total

1997 357 0 357 1997 357 0 357 1997 0 0 0

1998 1583 4 1587 1998 1583 4 1587 1998 0 0 0

1999 708 0 708 1999 708 0 708 1999 0 0 0

2000 336 11 347 2000 336 11 347 2000 0 0 0

2001 172 7 179 2001 172 7 179 2001 0 0 0

2002 405 3 408 2002 405 3 408 2002 0 0 0

2003 0 394 394 2003 0 394 394 2003 0 90 90

2004 131 0 131 2004 137 0 137 2004 119 0 119

2005 177 0 177 2005 177 0 177 2005 165 0 165

2006 75 0 75 2006 72 0 72 2006 88 0 88

2007 111 0 111 2007 170 0 170 2007 52 0 52

2008 189 0 189 2008 358 4 362 2008 8 47 55

2009 38 173 211 2009 74 370 444 2009 0 0 0

2010 23 298 321 2010 26 523 549 2010 0 1 1

2011 0 311 311 2011 0 606 606 2011 0 0 0

Total 4305 1201 5506 Total 4575 1922 6497 Total 432 138 570

Available Alpha BZ Results Available Beta BZ Results Available H3 BZ Results

 Dose analysis showed no significant change
Event Timeline after April 2019 AB ER Presentation

 April 17, 2019, Advisory Board Meeting 

• The AB assigned SC&A to perform a review of SEC-00188 Addendum 2 (Jan. 1, 

1997 – May 21, 2011)

 January 2020 Members of the SNL-A WG attended a site visit

• Included a focused tour

• Interview(s) in a conference room following the tour

 March 2020, the interview notes were sent to the participants for any comments or 

additional input. 

• There was quite a delay in getting feedback from the interviews and tour notes as 

the site was at a reduced work force as a result of COVID-19 pandemic

 August 24, 2020, the petitioner stated that he and the participants had no 

comments on the interview and tour notes from the site visit
Events after April 2019 AB ER Presentation, cont.

 During the week of 11/09/2020, SC&A’s report of their review of SEC Petition 

Evaluation Report: Petition SEC-00188, Addendum 2 made it through final 

classification review through DOE HQ

 12/04/20 SC&A submitted the OUO copy of their review of the SNL-A ER 

Addendum 2 to NIOSH and the AB

 03/01/21 SNL provided a UUR-Unclassified Unlimited Release of SC&A Review of 

the Sandia ER Addendum 2 to SC&A and DCAS

• SC&A had 1 finding and 7 observations
Events after April 2019 AB ER Presentation, cont.

 06/03/21, NIOSH provided a response paper titled "NIOSH Response to SC&A’s

Review of SEC-00188 Sandia ER Addendum 2"

 01/03/22 SC&A submitted SCA-TR-2021-SEC006, “Reply to NIOSH’s Response to

SC&A’s Review of the Sandia National Laboratories – Albuquerque SEC-00188

Addendum 2 Evaluation Report” to DCAS and the SNL WG