Cybersecurity Modernization Initiative

We are taking steps to continue to modernize and secure our data, applications, and systems. We completed the first phase and restored many of the functions put on pause in May 2021. Now that the first phase is complete, work will resume at a slower pace but will speed up as new systems and applications are brought online. For more information and updates, please visit our Cybersecurity Modernization Initiative web page.

Los Alamos National Laboratory (LANL)

On This Page

Special Exposure Cohort
Worker Outreach Activities
Advisory Board Work Group
Technical Documents
Advisory Board and NIOSH Discussions
Program Evaluation Plans and Reports (PEPs and PERs)
Public Comments
Document Archive

(Site Profile/Docket Number 027)

Location: Los Alamos, New Mexico

Also Known As: Los Alamos Scientific Laboratory

Special Exposure Cohort Petition Information

The Special Exposure Cohort (SEC) is a unique category of employees established by the Act (42 CFR Part 83). Claims compensated under the SEC do not have to go through the dose reconstruction process. To qualify for compensation under the SEC, a covered employee must meet specific requirements (e.g., must have at least one of 22 “specified cancers,” and have worked for a specified time period at one of the SEC sites). Classes of employees and work sites can be considered for addition to the SEC through a NIOSH petition process. More information about the Special Exposure Cohort can be found on our Frequently Asked Questions page.

Open/Active SEC Petitions

There is one open/active SEC petition from Los Alamos National Laboratory (LANL), Petition 109. The Advisory Board on Radiation and Worker Health has received the SEC Petition Evaluation Report from NIOSH, will review it, and will send its recommendation(s) to the Secretary of Health and Human Services.

Class(es) Added to the SEC

Employees of the Department of Energy (DOE), its predecessor agencies, or DOE contractors or subcontractors who were monitored or should have been monitored for radiological exposures while working in operational Technical Areas with a history of radioactive material use at the Los Alamos National Laboratory (LANL) for a number of work days aggregating at least 250 work days from March 15, 1943 through December 31, 1975, or in combination with work days within the parameters established for one or more other classes of employees in the Special Exposure Cohort.

Note: This class was established from Petition 51
Employees of the DOE predecessor agencies and their contractors or subcontractors who were monitored or should have been monitored for exposure to ionizing radiation associated with radioactive lanthanum (RaLa) operations at Technical Area 10 (Bayo Canyon Site), Technical Area 35 (Ten Site), and Buildings H, Sigma, and U (located within Technical Area 1) for a number of work days aggregating at least 250 work days during the period from September 1, 1944, through July 18, 1963, or in combination with work days within the parameters established for one or more classes of employees in the SEC.

Note: This class was established from Petition 61
All employees of the Department of Energy, its predecessor agencies, and their contractors and subcontractors who worked at the Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico from January 1, 1976, through December 31, 1995, for a number of work days aggregating at least 250 work days, occurring either solely under this employment or in combination with work days within the parameters established for one or more other classes of employees in the Special Exposure Cohort.

Note: This class was established from Petition 109
All employees of the Department of Energy, its predecessor agencies, and their contractors and subcontractors who worked at the Los Alamos National Laboratory in Los Alamos, New Mexico from March 15, 1943 through December 31, 1975, for a number of work days aggregating at least 250 work days, occurring either solely under this employment or in combination with work days within the parameters established for one or more other classes of employees in the Special Exposure Cohort.

Note: This class was established from Petition 170

Petitions Qualified for Evaluation

Below is a list of the petitions that qualified for evaluation. Select a petition on the list to view to the table for that particular petition.

Petition Information
Steps in Petition Process:	Petition Details:
Date Received	January 23, 2006
Date Qualified for Evaluation	August 2, 2006
Summary of Information in Petition	Job Titles and/or Job Duties: All Department of Energy employees, contractors, and subcontractors employed in all Tech areas Period of Employment: 1943 – 1975 Note: The information above is what qualified for evaluation. During our evaluation of whether dose reconstructions can adequately be completed for the above job titles and period of employment, information may cause NIOSH to change some the dates or job titles/duties. Therefore, as this petition proceeds through the SEC petition process and if an SEC class is proposed, the proposed class may not exactly match the above information.
Copy of the Petition Received	January 23, 2006 (January 1, 1943 – December 31, 1975) Pages 1-48 [2.0 MB (48 page)] Pages 49-97 [1.9 MB (49 page)] Pages 98-146 [3.3 MB (49 page)] Pages 147-192 [1.6 MB (46 page)]
Federal Register Notice Announcing that a Los Alamos National Laboratory (LANL) SEC Petition has met the Minimum Qualifications for Review and Evaluation	August 17, 2006 [40 KB (1 page)] (1943 – 1975)
SEC Petition Evaluation Report	February 6, 2007 [891 KB (117 pages)] (March 15, 1943 – December 31, 1975) Addendum #1 May 3, 2007 [20 KB (4 pages)] (March 15, 1943 – December 31, 1975) Addendum #2 June 5, 2007 [240 KB (10 pages)] (March 15, 1943 – December 31, 1975)
Evaluation Report Sent to the Advisory Board	February 6, 2007 (March 15, 1943 – December 31, 1975)
Petition Discussed by the Advisory Board	The Advisory Board discussed the petition on September 21, 2006, during its regular meeting. Note: Agendas and transcripts for Board meetings will be posted on the Advisory Board and Public Meetings page as soon as they become available.
Advisory Board Recommendation on SEC Petition	May 23, 2007 [543 KB (2 pages)] (March 15, 1943 – December 31, 1975)
HHS Letters to Congress Regarding the SEC Petition	June 22, 2007 [732 KB (6 pages)] (March 15, 1943 – December 31, 1975)
HHS Designation/Determination of Additional Members to the SEC	Designation: June 22, 2007 [499 KB (4 pages)] (March 15, 1943 – December 31, 1975) Note: A “designation” means that HHS is recommending a class be added to the SEC. A “determination” means that HHS is recommending a class not be added to the SEC.
Federal Register Notice: Designation/Determination of a Class of Employees for Addition to the Special Exposure Cohort	Designation: July 30, 2007 [40 KB (1 page)] (March 15, 1943 – December 31, 1975) Note: A “designation” will be published if there is a recommendation to add a class to the SEC. A “determination” will be published if there is a recommendation not to add a class to the SEC.
Effective Date for the SEC Class	July 22, 2007 (March 15, 1943 – December 31, 1975) Note: This only applies if the class is added to the SEC.
Federal Register Notice: Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort	August 7, 2007 [73 KB (1 page)] (March 15, 1943 – December 31, 1975) Note: This only applies if the class is added to the SEC.
Letter to DOL Regarding the Addition of a New Class of Employees to the SEC	July 30, 2007 [20 KB (1 page)] (March 15, 1943 – December 31, 1975) September 10, 2007 [63 KB (1 page)] (March 15, 1943 – December 31, 1975) Note: This only applies if the class is added to the SEC.

Petition Information
Steps in Petition Process:	Petition Details:
Date Received	June 5, 2006
Date Qualified for Evaluation	June 7, 2006
Summary of Information in Petition	Job Titles and/or Job Duties: All workers potentially exposed to radioactive lanthanum at the Technical Area 10 Bayo Canyon facility, TA-35 (Ten Site), or TA-1, buildings Sigma, H, and U Period of Employment: September 1, 1944 through July 18, 1963 Note: The information above is what qualified for evaluation. During our evaluation of whether dose reconstructions can adequately be completed for the above job titles and period of employment, information may cause NIOSH to change some the dates or job titles/duties. Therefore, as this petition proceeds through the SEC petition process and if an SEC class is proposed, the proposed class may not exactly match the above information.
Copy of the Petition Received	June 5, 2006 [88 KB (2 pages)] (September 1, 1944 through July 18, 1963)
Federal Register Notice Announcing that a Los Alamos National Laboratory (LANL) SEC Petition has met the Minimum Qualifications for Review and Evaluation	June 26, 2006 [42 KB (1 page)] (September 1, 1944 through July 18, 1963)
SEC Petition Evaluation Report	August 18, 2006 [86 KB (17 pages)] (September 1, 1944 through July 18, 1963)
Evaluation Report Sent to the Advisory Board	August 18, 2006 (September 1, 1944 through July 18, 1963)
Petition Discussed by the Advisory Board	The Advisory Board discussed the petition on February 17, 2009, during its regular meeting. Note: Agendas and transcripts for Board meetings will be posted on the Advisory Board and Public Meetings page as soon as they become available.
Advisory Board Recommendation on SEC Petition	October 11, 2006 [527 KB (2 pages)] (September 1, 1944 through July 18, 1963)
HHS Letters to Congress Regarding the SEC Petition	November 9, 2006 [506 KB (6 pages)] (September 1, 1944 through July 18, 1963)
HHS Designation/Determination of Additional Members to the SEC	Designation: November 9, 2006 [190 KB (4 pages)] (September 1, 1944 through July 18, 1963) Note: A “designation” means that HHS is recommending a class be added to the SEC. A “determination” means that HHS is recommending a class not be added to the SEC.
Federal Register Notice: Designation/Determination Regarding a Class of Employees for Addition to the Special Exposure Cohort	Designation: December 8, 2006 [103 KB (2 pages)] (September 1, 1944 through July 18, 1963) Note: A “designation” will be published if there is a recommendation to add a class to the SEC. A “determination” will be published if there is a recommendation not to add a class to the SEC.
Effective Date for the SEC Class	December 9, 2006 (September 1, 1944 through July 18, 1963) Note: This only applies if the class is added to the SEC.
Federal Register Notice: Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort	December 27, 2006 [50 KB (2 pages)] (September 1, 1944 through July 18, 1963) Note: This only applies if the class is added to the SEC.
Letter to DOL Regarding the Addition of a New Class of Employees to the SEC	December 12, 2006 [79 KB (1 page)] (September 1, 1944 through July 18, 1963) Note: This only applies if the class is added to the SEC.

Petition Information
Steps in Petition Process:	Petition Details:
Date Received	April 3, 2008
Date Qualified for Evaluation	May 29, 2008
Summary of Information in Petition	Location: Los Alamos, New Mexico Job Titles and/or Job Duties: All service support workers (which includes, but is not limited to, security guards, firefighters, laborers, custodians, carpenters, plumbers, electricians, pipefitters, sheet metal workers, ironworkers, welders, maintenance workers, truck drivers, delivery persons, radiation technicians, and area work coordinators) who worked in any operational Technical Areas with a history of radioactive material use. Period of Employment: January 1, 1976 through December 31, 2005 Note: The information above is what qualified for evaluation. During our evaluation of whether dose reconstructions can adequately be completed for the above job titles and period of employment, information may cause NIOSH to change some the dates or job titles/duties. Therefore, as this petition proceeds through the SEC petition process and if an SEC class is proposed, the proposed class may not exactly match the above information.
Copy of the Petition Received	April 3, 2009 [2.7 MB (111 pages)] (January 1, 1976 through December 31, 2005) Note: Due to their extensive number and size, some supplementary documents provided with the petition above are not posted on our website. These documents are available upon request.
Federal Register Notice Announcing that a Los Alamos National Laboratory (LANL) SEC Petition has met the Minimum Qualifications for Review and Evaluation	June 17, 2008 [42 KB (1 page)] (January 1, 1976 through December 31, 2005)
SEC Petition Evaluation Report	Revised August 15, 2012 [758 KB (98 pages)] (January 1, 1976 through December 31, 1995 Addendum April 24, 2017 [403 KB (55 pages)] (January 1, 1996 through December 31, 2005)
Evaluation Report Sent to the Advisory Board	August 22, 2012 (Revision 1) (January 1, 1976 through December 31, 1995) May 4, 2017 (Addendum) (January 1, 1996 through December 31, 2005)
Petition Discussed by the Advisory Board	The Advisory Board discussed the petition on November 16, 2010; May 3, 2007; June 19, 2012; September 18, 2012; August 23, 2017; and December 13, 2018, during its regular meetings. Note: Agendas and transcripts for Board meetings will be posted on the Advisory Board and Public Meetings page as soon as they become available.
Advisory Board Recommendation on SEC Petition	October 31, 2012 [62 KB (2 pages)] (January 1, 1976 through December 31, 1995)
HHS Letters to Congress Regarding the SEC Petition	December 7, 2012 [62 KB (10 pages)] (January 1, 1976 through December 31, 1995)
HHS Designation/Determination of Additional Members to the SEC	Designation: December 7, 2012 [33 KB (5 pages)] (January 1, 1976 through December 31, 1995) Note: A “designation” means that HHS is recommending a class be added to the SEC. A “determination” means that HHS is recommending a class not be added to the SEC.
Federal Register Notice: Designation/Determination of a Class of Employees for Addition to the Special Exposure Cohort	Designation: December 28, 2012 [49 KB (1 page)] (January 1, 1976 through December 31, 1995) Note: A “designation” will be published if there is a recommendation to add a class to the SEC. A “determination” will be published if there is a recommendation not to add a class to the SEC.
Effective Date for the SEC Class	January 6, 2013 (January 1, 1976 through December 31, 1995) Note: this only applies if the class is added to the SEC.
Federal Register Notice: Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort	January 17, 2013 [79 KB (1 page)] (January 1, 1976 through December 31, 1995) Note: this only applies if the class is added to the SEC.
Letter to DOL Regarding the Addition of a New Class of Employees to the SEC	January 7, 2013 [90 KB (1 page)] (January 1, 1976 through December 31, 1995) Note: this only applies if the class is added to the SEC.

Petition Information
Steps in Petition Process:	Petition Details:
Date Received	April 23, 2010
Date Qualified for Evaluation	April 27, 2010
Summary of Information in Petition	Job Titles and/or Job Duties: All employees of the Department of Energy, its predecessor agencies, and their contractors and subcontractors Period of Employment: March 15, 1943 through December 31, 1975 Note: The information above is what qualified for evaluation. During our evaluation of whether dose reconstructions can adequately be completed for the above job titles and period of employment, information may cause NIOSH to change some the dates or job titles/duties. Therefore, as this petition proceeds through the SEC petition process and if an SEC class is proposed, the proposed class may not exactly match the above information.
Copy of the Petition Received	April 23, 2010 [157 KB (2 pages)] (March 15, 1943 through December 31, 1975)
Federal Register Notice Announcing that a Los Alamos National Laboratory (LANL) SEC Petition has met the Minimum Qualifications for Review and Evaluation	May 6, 2010 [50 KB (2 pages)] (March 15, 1943 through December 31, 1975)
SEC Petition Evaluation Report	April 28, 2010 [117 KB (20 pages)] (March 15, 1943 through December 31, 1975)
Evaluation Report Sent to the Advisory Board	April 29, 2010 (March 15, 1943 through December 31, 1975)
Petition Discussed by the Advisory Board	The Advisory Board discussed the petition on May 20, 2010, and July 14, 2010, during its regular meeting. Note: Agendas and transcripts for Board meetings will be posted on the Advisory Board and Public Meetings page as soon as they become available.
Advisory Board Recommendation on SEC Petition	June 11, 2010 [34 KB (2 pages)] (March 15, 1943 through December 31, 1975)
HHS Letters to Congress Regarding the SEC Petition	July 13, 2010 [78 KB (10 pages)] (March 15, 1943 through December 31, 1975)
HHS Designation/Determination of Additional Members to the SEC	Designation: July 13, 2010 [35 KB (5 pages)] (March 15, 1943 through December 31, 1975) Note: A “designation” means that HHS is recommending a class be added to the SEC. A “determination” means that HHS is recommending a class not be added to the SEC.
Federal Register Notice: Designation/Determination Regarding a Class of Employees for Addition to the Special Exposure Cohort	Designation: July 30, 2010 [40 KB (1 page)] (March 15, 1943 through December 31, 1975) Note: A “designation” will be published if there is a recommendation to add a class to the SEC. A “determination” will be published if there is a recommendation not to add a class to the SEC.
Effective Date for the SEC Class	August 12, 2010 (March 15, 1943 through December 31, 1975) Note: This only applies if the class is added to the SEC.
Federal Register Notice: Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort	August 23, 2010 [39 KB (1 page)] (March 15, 1943 through December 31, 1975) Note: This only applies if the class is added to the SEC.
Letter to DOL Regarding the Addition of a New Class of Employees to the SEC	August 24, 2010 [21 KB (2 pages)] (March 15, 1943 through December 31, 1975) Note: This only applies if the class is added to the SEC.

SEC Petitions Not Qualifying for Evaluation

There were two additional petitions received that did not qualify for evaluation. One petition was withdrawn by the petitioner and the other petition did not meet the minimum petition requirements for evaluation.

Worker Outreach Activities

Based on a recommendation from the Advisory Board to provide workers and site experts with opportunities to participate in developing the technical documents used in dose reconstruction, NIOSH established a Worker Outreach Program.

At Worker Outreach Meetings, current and former DOE and AWE employees have opportunities to obtain information about Site Profiles, Technical Basis Documents, and Technical Information Bulletins, and to provide information for consideration and possible use in dose reconstruction. This process is valuable to ensure that the technical documents used in dose reconstruction contain correct and useful information.

Worker Outreach Activities for the Los Alamos National Laboratory (LANL)

September 17, 2008 (4:00 p.m.)
Meeting with New Mexico Building and Construction Trades Council (BCTC), Española, New Mexico

Final Minutes [60 KB (11 pages)]
September 17, 2008 (9:00 a.m.)
Meeting with International Association of Firefighters (IAFF) Local 3279, White Rock, New Mexico

Final Minutes [70 KB (14 pages)]
September 16, 2008 (6:30 p.m.)
Meeting with International Guards Union of America (IGUA) Local 69, Los Alamos, New Mexico

Final Minutes [37 KB (6 pages)]
September 16, 2008 (4:30 p.m.)
Meeting with International Guards Union of America (IGUA) Local 69, Los Alamos, New Mexico

Final Minutes [60 KB (11 pages)]
September 16, 2008 (9:00 a.m.)
Meeting with International Guards Union of America (IGUA) Local 69, Los Alamos, New Mexico

Final Minutes [58 KB (11 pages)]
May 10, 2007
Meeting with International Association of Firefighters (IAFF) Local 3279, Los Alamos County Fire Department, White Rock, New Mexico

Final Minutes [172 KB (16 pages)]
May 9, 2007
Meeting with International Association of Firefighters (IAFF) Local 3279, Los Alamos County Fire Department, White Rock, New Mexico

Final Minutes [108 KB (9 pages)]
May 9, 2007
Meeting with Executive Board of International Association of Firefighters (IAFF) Local 3279, Los Alamos County Fire Department, White Rock, New Mexico

Final Minutes [79 KB (6 pages)]
August 16, 2005
Meeting with International Guards Union of America Local 69, Los Alamos, New Mexico

Final Minutes [67 KB (16 pages)]
June 20, 2005
Meeting with New Mexico Building and Construction Trades Council, Albuquerque, New Mexico

Final Minutes [62 KB (5 pages)]
June 18, 2005
Meeting with University Professional and Technical Employees Local 1663 at Northern New Mexico Community College, Espanola, New Mexico

Final Minutes [126 KB (30 pages)]

Advisory Board Work Group on Los Alamos National Laboratory (LANL)

This Work Group is responsible for reviewing the Los Alamos Site Profile (as revised), the SEC petition(s) from Los Alamos petitioners, the NIOSH Evaluation Report of the petition, the SC&A Review of the Los Alamos Site Profile. It is also responsible for considering issues raised by the Board’s contractor (SC&A) concerning the Site Profile and the petition Evaluation Report, and for assisting NIOSH and SC&A in the resolution of such issues. The Work Group may recommend to the Board, changes in the Site Profile as appropriate. The Work Group should strive to develop a recommendation to the Board on whether a class should be added to the SEC.

Work Group Members:

Josie Beach (Chair)
Bradley P. Clawson
James E. Lockey, M.D.

Meeting Information:

March 23, 2022Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)

Time/Location:

11:00 a.m. (Eastern Time)
Meeting Type: Teleconference; Public, No Comment Period

Videoconference:

Join ZoomGov MeetingTeleconference Audio & Video
Meeting ID: 160 6763 3819
Passcode: ABRWH#01

Teleconference:

Phone: +1 (646) 828-7666 (U.S. East)Teleconference Phone
Phone: +1 (669) 254-5252 (U.S. West)Teleconference Phone
Meeting ID: 160 6763 3819
Passcode: 98685439
Find your local number

One Tap Mobile:
U.S. EastOne Tap Mobile
U.S. WestOne Tap Mobile

Join by H.323:
161.199.136.10 (U.S. East)
161.199.138.10 (U.S. West)
Meeting ID: 160 6763 3819
Passcode: 98685439

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [179 KB (1 page)]
- Transcript [381 KB (76 pages)]
Presentations:
- NIOSH/DCAS Presentation: Bounding Intakes of Exotic Radionuclides at Los Alamos National Laboratory (ORAUT-RPRT-101) [458 KB (37 pages)]
- NIOSH/DCAS Presentation: Assessment of Los Alamos National Laboratory Plutonium Bioassay Programs 1996 to 2001 (ORAUT- RPRT-0102) [1.3 MB (44 pages)]
Discussion/Background Papers:
July 25, 2019Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)

Time/Location:

10:30 a.m. (Eastern Time)
Meeting Type: Teleconference; Public, No Comment Period

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [102 KB (1 page)]
- Transcript [148 KB (24 pages)]
Presentations:
- NIOSH/DCAS: SEC-00109, Los Alamos National Laboratory (LANL) Status Update [889 KB (12 pages)]
Discussion/Background Papers:
- SC&A Memo: SC&A Review of “NIOSH Response to NTS Report NC ID 484 (LANL)” [120 KB (12 pages)]
  June 10, 2019
- NIOSH/ORAU: NIOSH Response to NTS Report NC ID 484 (LANL) [251 KB (31 pages)]
  March 26, 2019
November 29, 2018Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)

Time/Location:

10:30 a.m. (Eastern Time)
Meeting Type: Teleconference; Public, No Comment Period

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [53 KB (1 page)]
- Transcript [430 KB (78 pages)]
Presentations:
- NIOSH/DCAS: NIOSH’s Response to SC&A’s Review of the SEC-00109 LANL Addendum [858 KB (19 pages)]
- SC&A: SC&A Review of NIOSH White Paper “NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum” [316 KB (15 pages)]
Discussion/Background Papers:
- SC&A Draft: SC&A Review of White Paper, “NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum,” Revision 1 [516 KB (24 pages)]
  November 16, 2018
- NIOSH/ORAU: NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum, with Revised References Section and Appendix [496 KB (61 pages)]
  October 23, 2018
August 15, 2017Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

11:00 a.m. (Eastern Time)
Meeting Type: Teleconference; No Public Comment Period

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [24 KB (1 page)]
- Transcript [209 KB (91 pages)]
Presentations:
- NIOSH/DCAS: Los Alamos National Laboratory SEC-00109 Addendum [320 KB (33 pages)]
- SC&A: Review of SEC Petition Evaluation Report Addendum on Los Alamos National Laboratory [135 KB (8 pages)]
Discussion Papers:
September 11, 2012-MEETING TIME CHANGED
Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

1:00 p.m. Eastern Standard Time (EST)
Meeting Type: Teleconference; Public, No Comment Period

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [25 KB (1 page)]
- Transcript [148 KB (45 pages)]
Discussion Paper:
- LANL SEC Petition Evaluation Report SEC-109 (January 1, 1976 through December 31, 1995) [758 KB (98 pages)]
  Revised August 15, 2012
May 14, 2012
Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

9:00 a.m. Eastern Standard Time (EST)
Meeting Type: Teleconference; Public, No Comment Period

Cincinnati Airport Marriott
2395 Progress Dr.
Hebron, KY 41048
Phone: 859-586-0166

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [72 KB (1 page)]
- Transcript [1.7 MB (307 pages)]
Discussion Papers:
- Discussion Points for the ABRWH’S Work Group on LANL [308 KB (23 pages)]
  April 6, 2012
- NIOSH White Paper: LANL Neutron-to-Photon (NP) Dose Ratio Analysis [824 KB (71 pages)]
  March 29, 2012
- White Paper: Revision to Cerro Grande White Paper [1.3 MB (4 pages)]
  April 4, 2011
May 2, 2011
Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

9:00 a.m. Eastern Standard Time (EST)
Meeting Type: Face-to-Face; Public, No Comment Period

Cincinnati Airport Marriott
2395 Progress Dr.
Hebron, KY 41048
(859) 586-0166

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [16 KB (1 page)]
- Transcript [855 KB (332 pages)]
February 11, 2012-canceled
Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

9:00 a.m. Eastern Standard Time (EST)
Meeting Type: Teleconference; Public, No Comment Period

Cincinnati Airport Marriott
2395 Progress Dr.
Hebron, KY 41048

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

No Available Meeting Items
November 3, 2010
Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)Time/Location:

9:00 a.m. Eastern Standard Time (EST)
Meeting Type: Face-to-Face; Public, No Comment Period

Cincinnati Airport Marriott
2395 Progress Dr.
Hebron, KY 41048
Phone: (859) 586-0166

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- Agenda [9 KB (1 page)]
- Transcript [922 KB (361 pages)]
April 29, 2010
Meeting of the Advisory Board’s Work Group on LANLTime/Location:

9:30 a.m. Eastern Standard Time (EST)
Meeting Type: Face-to-Face; Public, No Comment Period

Cincinnati Airport Marriott
2395 Progress Dr.
Hebron, KY 41048
Phone: (859) 586-0166

Teleconference: +1-866-659-0537
Participant Code: 9933701

Pre-Decisional Document Policy

Available Meeting Items:
- An agenda will be provided at a later date.
- Transcript [694 KB (273 pages)]

Pre-Decisional Document Policy

Please Note: As part of the procedures and processes of the Advisory Board’s Work Groups, several kinds of pre-decisional documents may be developed. These pre-decisional documents, such as white papers, matrices, working drafts, etc., are distributed among Work Group members as research and background tools to facilitate discussion and deliberation. Although discussion during a public meeting may cover pre-decisional documents, these documents often are not further revised or finalized, and thus do not reflect the final determination or evaluation of the Advisory Board and its Work Groups. Additionally, some pre-decisional documents not otherwise posted on the website may contain sensitive information, which would require an interested party to obtain such documents by filing a Freedom of Information Act (FOIA) request with the CDC/ATSDR FOIA Office at FOIARequests@cdc.gov.

Technical Documents

If the energy employee’s personal radiation information is incomplete, NIOSH will use other sources to estimate the radiation dose. This may involve using technical documents called Site Profiles, Technical Basis Documents, and Technical Information Bulletins.

Site Profile

Introduction [114 KB (10 pages)]
Revised October 1, 2007

Revision Includes: Initiated to include References and Attributions and Annotations sections. Minor editorial changes made. No further changes occurred as a result of formal internal review. Incorporates formal NIOSH review comments.
Site Description [505 KB (65 pages)]
Approved May 7, 2004
Occupational Medical Dose [716 KB (29 pages)]
Revised January 10, 2023

Revision Includes: Revised to remove X-ray doses and to reference ORAUT-OTIB-0006 in their place. Site-specific X-ray doses recalculated. Recalculated uncertainty using 24-cm torso thickness. This revision results in a change in the assigned doses. Incorporates formal internal and NIOSH review comments. Constitutes a total rewrite of the document.
Occupational Environmental Dose [1.6 MB (96 pages)]
Revised March 26, 2010

Revision Includes: Adds new environmental external and uptake data prior to 1971. Added Attributions and Annotations section. Incorporated SEC-000170 and SEC-00051. Intakes to assign maximum doses for four primary radionuclides during the specified employment period for the class of Los Alamos National Laboratory employees added to the Special Exposure Cohort (1943-1975) are included. Section 4.1.3.3 clarified ‘partial’ dose reconstruction with respect to ambient external dose; additional instructions to dose reconstructors were added to section 4.3.1, ‘Ambient Radiation.’ These state that on-site ambient dose is to be based on the environmental film badge and TLD results available from 1965 onward. In support of this, rows with years prior to 1965 were deleted from Table 4-26. Single correction to a preposition in Section 4.2.1. Incorporates review comments from formal internal and NIOSH review. Incorporates changes required by the adoption of an 83.14 SEC determination. This alters the definition of the class of Los Alamos National Laboratory employees added to the SEC (1943-1975), and removes the area-specific and monitoring restrictions from the class definition making the SEC class now include all employees in all areas of the LANL during the period 1943-1975. Constitutes a total rewrite of the document.
Occupational Internal Dose [940 KB (117 pages)]
Revised April 18, 2013

Revision Includes: Incorporates SEC-00109. Removed provisions to estimate unmonitored intakes consistent with the wording in the Advisory Board recommendation (Melius 2012). Incorporates formal internal and NIOSH review comments. Constitutes a total rewrite of the document.
Occupational External Dose [1 MB (79 pages)]
Revised March 21, 2013

Revision Includes: Incorporates dose reconstruction limitations that relate to a class of LANL employees added to the SEC comprised of all workers from January 1, 1976, to December 31, 1995, SEC-00109 (NIOSH 2012). Attachment B has been added, which contains an analysis that evaluates the neutron-to-photon ratios promulgated in earlier revisions of the TBD. No changes were made to the neutron-to-photon ratios as a result. Incorporates formal internal and NIOSH review comments. For the years 1976-1980, NIOSH has agreed, in addressing comments on the TBD, to assign neutron dose using the 95th-percentile value of the NP ratio to address uncertainties associated with the transition from film to TLD dosimeters in response to the LANL ABRWH Work Group. Constitutes a total rewrite of the document.

Technical Information Bulletins (TIBs)

Internal Dosimetry Co-Exposure Data for Los Alamos National Laboratory [1.8 MB (113 pages)]

Document Number: ORAUT-OTIB-0062 Rev-01

About this Document: Provides information for internal dosimetry coworker data for Los Alamos National Laboratory. Incorporates formal internal and NIOSH review comments. Analysis of plutonium-239 and cesium-137 lung counts updated and new guidance added for Type Super S plutonium-239.

Revised: September 1, 2020

Revision Includes: Revision initiated to include the intake rates for type SS plutonium. Incorporates formal internal and NIOSH review comments. Constitutes a total rewrite of the document.

Note: Title changed from "Internal Dosimetry Coworker Data for Los Alamos National Laboratory" to "Internal Dosimetry Co-Exposure Data for Los Alamos National Laboratory" to accurately describe the coworker model as a co-exposure model. Previous versions of the is document are located on this page under the Document Archive for Technical Information Bulletins (TIBs) section.

Advisory Board and NIOSH Discussions on Los Alamos National Laboratory (LANL)

The Los Alamos National Laboratory (LANL) discussion papers listed below are working documents prepared by NIOSH or its contractor for use in discussions with the Advisory Board on Radiation and Worker Health or its Working Groups or Subcommittees. Draft, preliminary, interim, and white paper documents are not final NIOSH or Advisory Board (or their technical support and review contractors) positions unless specifically marked as such. These documents represent preliminary positions taken on technical issues prepared by NIOSH or its contractor.

The discussion papers have been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and have been cleared for distribution.

SC&A Draft: SC&A Review of Remaining Internal Dose Issues for the LANL SEC-0109 Addendum Period (1996–2000) [1 MB (103 pages)]
Contract No. 75D30119C04183
Document No. SCA-TR-2023-SEC002, Revision 0
April 12, 2024
NIOSH/DCAS Memo: Weight of Evidence Supports NIOSH’s Ability to Bound LANL TA-53 Doses for 1996–2005: Evaluation of Radiological Work Permits [621 KB (14 pages)]
February 22, 2024
NIOSH/ORAU: ORAUT-RPRT-0107, Dose Estimation from Intakes of Exotic Radionuclides at the Los Alamos Neutron Science Center, 1996 to 2005, Revision 00 [721 KB (33 pages)]
September 15, 2023
NIOSH/ORAU: ORAUT-RPRT-0101, Bounding Intakes of Exotic Radionuclides at Los Alamos National Laboratory, Revision 01 [970 KB (54 pages)]
August 30, 2023
NIOSH/DCAS Memo: Weight of Evidence Supports NIOSH’s Ability to Bound LANL TA-53 Doses for 1996–2005 [496 KB (16 pages)]
August 15, 2023
NIOSH/ORAU: ORAUT-RPRT-0103, Review of Potential Exposure to Exotic Radionuclides Using Radiological Work Permit Data at Los Alamos National Laboratory, Revision 00 [470 KB (38 pages)]
August 15, 2022
NIOSH/DCAS Presentation: Assessment of Los Alamos National Laboratory Plutonium Bioassay Programs 1996 to 2001 (ORAUT- RPRT-0102) [1.3 MB (44 pages)]
Presentation at the March 23, 2022, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
NIOSH/ORAU: ORAUT-RPRT-0101, Bounding Intakes of Exotic Radionuclides at Los Alamos National Laboratory, Revision 00 [826 KB (56 pages)]
March 1, 2022
NIOSH/DCAS: Bounding Intakes of Exotic Radionuclides at Los Alamos National Laboratory (ORAUT-RPRT-101) [458 KB (37 pages)]
Presentation at the March 23, 2022, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
NIOSH/ORAU: ORAUT-RPRT-0102, Assessment of Los Alamos National Laboratory Plutonium Bioassay Programs 1996 to 2001, Revision 00 [713 KB (51 pages)]
December 2, 2021
SC&A Draft: SC&A’s Evaluation of ORAUT-OTIB-0049, Revision 02, “Estimating Doses for Plutonium Strongly Retained in the Lung” [1.3 MB (39 pages)]
Contract No. 75D30119C04183
Document No. SCA-TR-2021-PR049, Revision 0
October 7, 2021
SC&A Draft: SC&A’S Evaluation Of ORAUT-OTIB-0088, Revision 01, “External Dose Reconstruction” [296 KB (9 pages)]
Contract No. 75D30119C04183
Document No. SCA-TR-2021-PR088, Revision 0
September 3, 2021
NIOSH/DCAS Presentation: SEC-00109, Los Alamos National Laboratory (LANL) Status Update
Presented at the July 25, 2019, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
SC&A Memo: SC&A Review of “NIOSH Response to NTS Report NC ID 484 (LANL)” [120 KB (12 pages)]
June 10, 2019
NIOSH/ORAU: NIOSH Response to NTS Report NC ID 484 (LANL) [251 KB (31 pages)]
March 26, 2019
SC&A Draft: SC&A’s Review of White Paper, “NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum” [228 KB (24 pages)]
Contract No. 211-2014-58081
SCA-TR-2018-SEC005, Revision 2
January 9, 2019
SC&A Memo: Clarification Comments about NIOSH White Paper Response (September 12, 2018), Appendix A, “SEC-00109 LANL Petitioner Issues and Resolutions” [34 KB (2 pages)]
January 4, 2019
NIOSH/DCAS/SC&A: NIOSH and SC&A Reviews of Issues with SEC-00109 LANL Addendum [781 KB (20 pages)]
Presentation at the December 12-13, 2018, Meeting of the Advisory Board on Radiation and Worker Health
NIOSH/DCAS: NIOSH’s Response to SC&A’s Review of the SEC-00109 LANL Addendum [858 KB (19 pages)]
Presentation at the November 29, 2018, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
SC&A Presentation: SC&A Review of NIOSH White Paper “NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum” [316 KB (15 pages)]
Presentation at the November 29, 2018, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
SC&A Draft: SC&A Review of White Paper, “NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum” [516 KB (24 pages)]
Contract No. 211-2014-58081
SCA-TR-2018-SEC005, Revision 1
November 16, 2018
NIOSH/ORAU: NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum, with Revised References Section and Appendix [496 KB (61 pages)]
October 23, 2018
NIOSH/ORAU: NIOSH Response to SC&A’s Review of the SEC-00109 LANL Addendum [514 KB (54 pages)]
September 12, 2018
SC&A Presentation: Review of SEC Petition Evaluation Report Addendum Los Alamos National Laboratory [146 KB (8 pages)]
Presentation at the August 23-24, 2017, Meeting of the Advisory Board on Radiation and Worker Health
NIOSH/DCAS: Los Alamos National Laboratory SEC Evaluation Summary [362 KB (33 pages)]
Presentation at the August 23-24, 2017, Meeting of the Advisory Board on Radiation and Worker Health
SC&A Presentation: Review of SEC Petition Evaluation Report Addendum on Los Alamos National Laboratory [135 KB (8 pages)]
Presentation at the August 15, 2017, Teleconference Meeting of the Advisory Board’s Work Group on Los Alamos National Laboratory (LANL)
SC&A Memo: Review of SEC Petition Evaluation Report Addendum (SEC-00109) for Los Alamos National Laboratory [124 KB (16 pages)]
July 27, 2017
SC&A Memo: Remaining Site Profile (TBD) Issues [63 KB (5 pages)]
March 10, 2017
SC&A Draft: Review of Responsiveness to Worker Comments for Los Alamos National Laboratory, Rev. 2 [2 MB (219 pages)]
June 11, 2014
SC&A Draft: OCAS-PER-018, Subtask 4 – Review of Five Advisory Board Selected Cases Reworked for the Evaluation of Los Alamos National Laboratory, Occupational External Dose Technical Basis Document Revisions [667 KB (33 pages)]
May 30, 2014
SC&A Presentation: Review of NIOSH Responsiveness to Worker Comments for Los Alamos National Laboratory [130 KB (13 pages)]
Teleconference Meeting of the Advisory Board’s Work Group on Worker Outreach
June 5, 2014
SC&A Draft Report to the Subcommittee on Dose Reconstruction: Summary of Findings Matrix (10th–13th Sets: RFP/LANL Cases) [363 KB (32 pages)]
November 21, 2012
NIOSH Presentation: Los Alamos National Laboratory SEC Petition (1976-1995) [250 KB (19 pages)]
September 18, 2012
SC&A Memo: Comments Regarding Cerro Grande White Paper (Revision 01, April 4, 2011) [25 KB (3 pages)]
May 30, 2012
SC&A Draft: Review of NIOSH’s Evaluation Report for Los Alamos National Laboratory Special Exposure Cohort Petition SEC-00109: Preliminary Issues – Availability of Bioassay Records and Adequacy of In-vivo Dosimetry [359 KB (53 pages)]
Contract No. 200-2009-28555
SCA-TR-SEC2010-0004, Revision 0
April 2010
SC&A Draft: Los Alamos National Laboratory Site Profile Review [1.2 MB (214 pages)]
Contract No. 200-2004-03805
Task Order No. 1
August 2006

Program Evaluation Plans (PEPs) and Program Evaluation Reports (PERs)

NIOSH is committed to applying the best available science in dose reconstructions. In keeping with this commitment, completed cases with probabilities of causation less than 50% are reviewed as relevant new information becomes available. The results of these reviews are described in a Program Evaluation Report (PER). The PER details the effect, if any, of the new information on the completed dose reconstruction. If it appears that the new information may result in an increase in dose for a completed dose reconstruction with a probability of causation of less than 50%, NIOSH is committed to working with the Department of Labor to reopen and rework the dose reconstruction, as appropriate. A Program Evaluation Plan (PEP) describes plans for evaluating specific program details or issues.

OCAS-PER-0018 Rev-00: Program Evaluation Report: Los Alamos National Laboratory TBD Revision [18 KB (2 pages)]
July 31, 2007

About this Document: New document to determine which previously completed claims require evaluation for the effect of revising the LANL TBD.

Summary: It is not possible to precisely determine the effect of the change to LAMPF dose estimates on Probability of Causation without a new Dose Estimate. However, it is possible to determine if the LAMPF energy distribution was used in the original dose estimate. It is also possible to determine if an individual was assigned unmonitored neutron dose based on neutron to photon ratios and whether the ratio used will increase or decrease under the new revision to the TBD.In order to determine the effect of these factors, the individual cases must be re-examined. Since the unmonitored neutron dose has the potential of affecting every claim, all claims completed prior to May 30, 2007 from Los Alamos National Laboratory with a Probability of Causation less than 50% will require a review. NIOSH will request claims be returned in which the LAMPF energy distributions were originally assigned using Revision 0 for a new dose estimate. NIOSH will also request the return of claims in which the original dose estimate utilized a neutron to photon ratio that has now increased. For all other claims, NIOSH will review the claim against any other revisions to other technical documents that may affect the claim. DOL will be provided with a statement for each claim indicating what changes the claim was reviewed against and why the change did not affect the particular dose estimate or the Probability of Causation calculation. For any claims where it is not possible to provide this statement without a new Dose Estimate, NIOSH will request that DOL return the claim for a new Dose Estimate.

NIOSH has determined that 300 claims meet the criteria for further review. The remaining cases with a probability of causation less than 50% (1 claim) were completed using revision 1 of the TBD. NIOSH will provide DOL with the list of 300 claims as well as a determination on each claim as to whether a new Dose Estimate is required.

Public Comments on Los Alamos National Laboratory (LANL) Documents

How to Submit Comments

Comments on Los Alamos National Laboratory (LANL) Documents can be submitted to the NIOSH Docket Officer electronically by email at nioshdocket@cdc.gov or printed comments can be mailed to:

NIOSH Docket Office
Robert A. Taft Laboratories, MS-C34
1090 Tusculum Avenue
Cincinnati, OH 45226
Please include the Site Profile/Docket Number (027) on all comments.

Comments Received

Document Archive for Los Alamos National Laboratory (LANL)

Site Profile Document Archive

Site Profile: Introduction [43 KB (8 pages)]
January 25, 2005
Site Profile: Occupational Medical Dose
- Revised September 14, 2010 [219 KB (18 pages)]
  
  Revision Includes: Revised to incorporate data captured since the last revision to better document what has come to be known about PFG at LANL, and to add skin doses for all projections and periods. Added references and included Attributions and Annotations Section. Incorporates formal internal and NIOSH review comments. Constitutes a total rewrite of the document.
- Approved December 29, 2004 [193 KB (23 pages)]
  
  About this Document: Technical basis document for the Los Alamos National Laboratory – Occupational Medical Dose. Incorporates comments from internal and NIOSH reviews.
Site Profile: Occupational Environmental Dose [2 MB (96 pages)]
October 8, 2004
Site Profile: Occupational Internal Dose section
- Revised October 15, 2009 [1.3 MB (150 pages)]
  
  Revision Includes: Incorporates information from documents not available at the time the original document was published. The current information available for uranium has been incorporated into Section 5.2.4. Clarification of MDAs, UNAA/DNAA analysis results, guidance for selection of enrichment, and a description of the new LANL Bioassay Repository database content have been included. Appropriate references have been added. For claims involving uranium UNAA bioassay results: Because of the ambiguity in the interpretation of the uranium bioassay results when results were transferred into the Bioassay Repository, the guidance in the TBD might not have been interpreted consistently by DRs and PRs. UNAA/DNAA data provided by LANL is for DU and EU rather than U-238 and U-235. A table providing an aged “pure” 238Pu mixture has been provided for use when exposures to heat source technology plutonium is suspected. Changes to the mixture might affect the total dose for plutonium intakes evaluated as “pure” 238Pu. In addition, the Tiger Team Assessment (DOE 1991), the Human Experiments and the details of the RaLa SEC Report (NIOSH 2006) have been included in the revision. Incorporates formal internal and NIOSH review comments. Adds Attributions and Annotations section. A description of the class of employees added to the SEC for SEC Petition-00051 was added to the text describing the class of employees added under SEC Petition-000170 (employees associated with RaLa operations). A new Section 5.2.4.6 was added describing the limitations on internal dose reconstruction for employees in the non-excepted TAs (as listed in the petition). Added statement about only partial dose reconstructions are possible for most TAs. A new bullet was added in Section 5.7.2, General Guidance, indicating that only partial internal dose reconstructions are possible. Incorporates methods for estimating maximum doses in accordance with the evaluation report for Petition SEC-00109, changes to address comments by OCAS commenters, updated dose reconstruction methodologies and references, and addition of an algorithm to guide dose reconstructors for dose calculation and dose assignment. Constitutes a total rewrite of the document.
- Approved December 21, 2004 [920 KB (96 pages)]
Site Profile: Occupational External Dose section
- Occupational External Dose [1.1 MB (77 pages)]
  Revised November 23, 2009
  
  Revision Includes: Updated NIOSH references in Sections 6-1, 6-2, A-6 and Reference Section. Added details to the Scope in Section 6.1. In Section 6.2, “Reporting Practices” was modified to distinguish between LANL records with non-penetrating dose listed as “SHALLOW” vs. those listed as “SKIN.” Several changes were made to remove dose reconstruction methods and information relating to periods when it has been determined to be infeasible to estimate external doses. Specifically, according to the HHS letter adding a class of LANL employees to the SEC (1943-1975), partial dose reconstructions may include external doses from gamma emitters in the years 1946-1975, neutrons from 1946-1975, and beta-emitters in the years 1949-1975. Incorporates formal internal and NIOSH review comments. No sections were deleted.
- Revised May 30, 2007 [881 KB (76 pages)]
  
  Revision Includes: Adds Purpose and Scope sections. Constitutes a total rewrite of document. Adds Attributions and Annotations section. Incorporates formal internal and NIOSH review comments. This revision results in an increase in assigned dose and a PER is required due to the addition of median photon adjustment values in Tables 6-22 and A-8; otherwise, the maximum values were replaced with lower 95th percentiles, and therefore would lower doses. An exception to the lower 95th-percentile values is the value for Other Operations, which is higher than the previously reported maximum value of annual geometric means. This change will result in a higher dose. Changes in Table A-7 will increase skin/shallow dose for LAMPF/LANSCE workers.
- Approved May 10, 2005 [832 KB (72 pages)]

Special Exposure Cohort (SEC) Petition Document Archive

Special Exposure Cohort (SEC) Petition Evaluation Report: Petition 109
- Approved January 22, 2009 (Rev. 0) [1.2 MB (77 pages)]

Technical Information Bulletins (TIBs) Document Archive

Internal Dosimetry Coworker Data for Los Alamos National Laboratory [942 KB (104 pages)]

Document Number: ORAUT-OTIB-0062 Rev-00

About this Document: Provides information for internal dosimetry coworker data for Los Alamos National Laboratory. Incorporates formal internal and NIOSH review comments. Analysis of plutonium-239 and cesium-137 lung counts updated and new guidance added for Type Super S plutonium-239.

Approved: October 15, 2009

Note: Title changed from “Internal Dosimetry Coworker Data for Los Alamos National Laboratory” to “Internal Dosimetry Co-Exposure Data for Los Alamos National Laboratory” on September 1, 2020, to accurately describe the coworker model as a co-exposure model.