NIST HANDBOOK 150 - 4

2019 Edition

National

Voluntary

Laboratory

Accreditation

Program

IONIZING

RADIATION

DOSIMETRY

Derek L. Ho

National Voluntary Laboratory Accreditation Program

Division of Standards Services

Technology Services

This publication is available free of charge from:

https://doi.org/10.6028/NIST.HB.150-4-2019

November 2019

U.S. Department of Commerce

Wilbur Ross, Secretary

National Institute of Standards and Technology

Walter G. Copan, Director
NVLAP AND THE NVLAP LOGO

The term NVLAP and the NVLAP logo are federally 

registered certification marks of the National Institute 

of Standards and Technology and the federal 

government, who retain exclusive rights to control the 

use thereof. Permission to use the term and/or logo is 

granted to NVLAP-accredited laboratories for the 

limited purposes of announcing their accredited status, 

and for use on reports that describe only testing and 

calibration within the scope of accreditation. NIST 

reserves the right to control the quality of the use of 

the term NVLAP and of the NVLAP logo.
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Contents

Contents.......................................................................................................................................................iii

Foreword.......................................................................................................................................................v

Introduction..................................................................................................................................................vi

1 General information..............................................................................................................................1

1.1 Scope ..........................................................................................................................................1

1.2 Organization of handbook ..........................................................................................................1

1.3 Program description....................................................................................................................1

1.4 References ..................................................................................................................................2

1.5 Terms and definitions.................................................................................................................2

1.6 Program documentation..............................................................................................................3

2 LAP establishment, development and implementation.........................................................................4

3 Accreditation process............................................................................................................................4

3.1 General........................................................................................................................................4

3.2 Management system review .......................................................................................................4

3.3 On-site assessment......................................................................................................................5

3.4 Proficiency testing ......................................................................................................................7

4 General requirements............................................................................................................................9

4.1 Impartiality .................................................................................................................................9

4.2 Confidentiality............................................................................................................................9

5 Structural requirements.........................................................................................................................9

6 Resource requirements........................................................................................................................10

6.1 General......................................................................................................................................10

6.2 Personnel ..................................................................................................................................10

6.3 Facilities and environmental conditions...................................................................................10

6.4 Equipment.................................................................................................................................10

6.5 Metrological traceability...........................................................................................................12

6.6 External provided products and services..................................................................................12

7 Process requirements ..........................................................................................................................12

7.1 Review of requests, tenders and contracts................................................................................12

7.2 Selection, verification and validation of methods ....................................................................12

7.3 Sampling...................................................................................................................................12

7.4 Handling of test or calibration items.........................................................................................13

7.5 Technical records......................................................................................................................13

7.6 Evaluation of measurement uncertainty ...................................................................................13

7.7 Ensuring the validity of results.................................................................................................13

7.8 Reporting of results...................................................................................................................14

7.9 Complaints................................................................................................................................15

7.10 Nonconforming work................................................................................................................15
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7.11 Control of data and information management ..........................................................................15

8 Management system requirements......................................................................................................15

8.1 Options......................................................................................................................................15

8.2 Management system documentation.........................................................................................15

8.3 Control of management system documents..............................................................................15

8.4 Control of records (Option A) ..................................................................................................16

8.5 Actions to address risks and opportunities ...............................................................................16

8.6 Improvement.............................................................................................................................16

8.7 Corrective actions.....................................................................................................................17

8.8 Internal audits...........................................................................................................................17

8.9 Management reviews................................................................................................................17

9 Additional requirements......................................................................................................................17
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Foreword

The National Institute of Standards and Technology (NIST) Handbook 150 publication series sets forth the 

procedures, requirements, and guidance for the accreditation of testing and calibration laboratories by the 

National Voluntary Laboratory Accreditation Program (NVLAP). The series comprises the following 

publications:

• NIST Handbook 150, NVLAP Procedures and General Requirements, which contains the general 

procedures and requirements under which NVLAP operates as an unbiased third-party accreditation 

body;

• NIST Handbook 150-xx program-specific handbooks, which supplement NIST Handbook 150 by 

providing additional requirements, guidance, and interpretive information applicable to specific 

Laboratory Accreditation Programs (LAPs) under NVLAP.

The program-specific handbooks are not standalone documents, but rather are companion documents to 

NIST Handbook 150 and the referenced ISO/IEC 17025 requirements. Each program-specific handbook 

tailors the general criteria referenced in NIST Handbook 150 to the specific test methods, calibrations, or 

types of tests or calibrations covered by a LAP.

NIST Handbook 150-4, NVLAP Ionizing Radiation Dosimetry, presents the technical requirements and 

guidance for the accreditation of laboratories under the NVLAP Ionizing Radiation Dosimetry LAP. The 

2019 edition incorporates changes resulting from the release of the newest edition of ISO/IEC 17025:2017, 

General requirements for the competence of testing and calibration laboratories, and NIST Handbook 150

(2016), as well as editorial improvements. The 2019 edition of NIST Handbook 150-4 supersedes and 

replaces the 2005 edition.

The handbook was revised with the participation of technical experts in the field of ionizing radiation 

dosimetry and was approved by NVLAP. The following main changes have been made to this handbook 

with respect to the previous edition:

• the numbering has been aligned to ISO/IEC 17025:2017, General requirements for the competence of 

testing and calibration laboratories (hereafter referred to as ISO/IEC 17025);

• requirements that closely duplicated existing requirements in either ISO/IEC 17025 or NIST Handbook 

150 have been removed;

• all references to applicable international guides and standards have been updated.

This handbook is also available on the NVLAP website (https://www.nist.gov/nvlap).

Questions or comments concerning this handbook should be submitted to NVLAP, National Institute of 

Standards and Technology, 100 Bureau Drive, Stop 2140, Gaithersburg, MD, 20899-2140; phone: 301-975-

4016; fax: 301-926-2884; e-mail: nvlap@nist.gov.
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Introduction

The laboratory accreditation program for Ionizing Radiation Dosimetry was established in 1984 in response 

to a request from the U.S. Nuclear Regulatory Commission (NRC). The purpose of the NVLAP Ionizing 

Radiation Dosimetry Program is to recognize competent dosimetry processing laboratories and to improve 

the quality of personnel dosimetry by providing periodic evaluations of each laboratory, including an 

assessment of the laboratory's management system. 

Accreditation is available to any laboratory that processes radiation dosimeters used to monitor individual 

exposure to ionizing radiation. A foreign-based laboratory may also be accredited by NVLAP if the 

laboratory meets the same requirements as domestic laboratories and pays any required additional fees 

associated with the on-site assessment.

The processing laboratories are referred to as dosimetry processors. In this handbook, the terms laboratory

and processor are used interchangeably. 

The ionizing radiation dosimetry standards were developed by the American National Standards Institute 

(ANSI) and the Health Physics Society (HPS). The dosimetry processors follow the current versions 

(unless noted by a NVLAP laboratory bulletin) of ANSI/HPS N13.11, Personnel Dosimetry Performance 

– Criteria for Testing, for whole body dosimeters, and ANSI/HPS N13.32, Performance Testing of 

Extremity Dosimeters for extremity dosimeters. 

To be granted accreditation, a dosimetry processor shall satisfy the NVLAP requirements contained in 

ISO/IEC 17025, NIST Handbook 150 and this handbook, and shall demonstrate proficiency in processing 

each dosimeter model/type that the laboratory intends to use in each radiation category for which 

accreditation is desired.
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1 General information

1.1 Scope

1.1.1 NIST Handbook 150-4 specifies the technical requirements and provides guidance for the 

accreditation of laboratories under the Ionizing Radiation Dosimetry LAP. This handbook supplements the 

NVLAP programmatic procedures and general requirements found in NIST Handbook 150.

1.1.2 This handbook also identifies the requirements for a management system, the specific on-site 

assessment criteria and requirements for proficiency testing to ANSI/HPS N13.11 and ANSI/HPS N13.32. 

The interpretive comments and additional requirements contained in this handbook make the general 

NVLAP criteria specifically applicable to the Ionizing Radiation Dosimetry LAP.

1.1.3 This handbook is intended for information and use by accredited dosimetry processors, assessors 

conducting on-site assessments, laboratories seeking accreditation, other laboratory accreditation systems, 

users of laboratory services, and others needing information on the requirements for NVLAP accreditation

under the Ionizing Radiation Dosimetry LAP.

1.1.4 The requirements of NIST Handbook 150 and the referenced ISO/IEC 17025 requirements, the 

interpretations and specific requirements in this handbook, and the requirements of the test standards for 

which the laboratory seeks accreditation (i.e., ANSI/HPS N13.11, ANSI/HPS N13.32, etc.) must be 

combined to produce the criteria for accreditation in the Ionizing Radiation Dosimetry LAP.

1.2 Organization of handbook

The numbering and titles of the first three clauses of this handbook match those of NIST Handbook 150.

However, unless there is an additional requirement, only the top-level numbering (e.g., 1, 2, and 3) is listed.

The numbering and titles of clauses four through eight of this handbook mirror those of ISO/IEC 17025. 

For clarity, the top-level and first sub-level clauses (e.g., 4, 5, 4.1, 4.2, etc.) are also numbered and titled to 

correspond with ISO/IEC 17025, even when there are no additional requirements given in this handbook. 

1.3 Program description

1.3.1 This accreditation program is designed to satisfy the requirements of contractors, state and local 

governments, and federal agencies specifying accreditation for laboratories that process ionizing radiation 

dosimeters.

1.3.2 Accreditation is available to any organization that processes personnel radiation dosimeters used 

to monitor individual whole body or extremity radiation dose received from exposure to ionizing radiation.

1.3.3 Processors who provide dosimetry services to internal clients (i.e., dosimeters are issued to workers 

under the same organization, such as a utility company with a dosimetry processing division) shall ensure

that the laboratory's scope of accreditation is appropriate to meet state and federal requirements for the 

worker who was issued a dosimeter.
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1.3.4 Processors who provide dosimetry services to external clients shall clearly communicate to the

client the scope of the processor's accreditation, including radiation categories for each type and model of 

dosimeter provided.

1.3.5 NVLAP does not prohibit a processor from providing additional services outside the scope of its 

accreditation, but those services shall be clearly identified in client reports as not being in the scope of the 

laboratory's NVLAP accreditation.

1.3.6 Processors may utilize dosimeters and processing techniques of their choice. However, once 

accredited, the dosimeters and processing techniques used to provide accredited dosimetry in the normal 

conduct of work shall be the same as those that were used in demonstrating proficiency.

1.3.7 The processor shall notify the NVLAP Program Manager of any changes or deviations from the 

specified dosimeters or processing techniques and provide evidence of satisfactory proficiency testing for 

those dosimeters or processing techniques before the new dosimeters and techniques can become a part of 

the processor's scope of accreditation.

1.4 References

The following documents are referenced in this handbook. For dated references, only the edition cited 

applies. For undated references, the latest edition of the referenced document (including any amendments) 

shall apply within one year of publication or within another time limit specified by regulations or other 

requirement documents.

— ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories

— NIST Handbook 150, NVLAP Procedures and General Requirements

— ANSI/HPS N13.11:2009, Personnel Dosimetry Performance - Criteria for Testing 

— ANSI/HPS N13.32:2008, Performance Testing of Extremity Dosimeters

— IEEE Standard 1012:2012, IEEE Standard for Software Verification and Validation

— Code of Federal Regulations, 10 CFR Part 20, Standards for Protection Against Radiation

1.5 Terms and definitions

For the purposes of this handbook, the terms and definitions given in NIST Handbook 150, ANSI N13.11, 

ANSI N13.32, and the following definitions apply.

1.5.1 

absorbed dose, D

The energy absorbed per unit mass at a specific point in a material. The unit of dose is the gray (Gy), which 

has units of joules per kilogram (J/kg). Formerly, the special unit of absorbed dose was the rad; 1 J/kg = 1 

Gy = 100 rad.
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1.5.2 

angular dependence 

The performance of a dosimeter irradiated under non-perpendicular radiation incidence.

1.5.3 

dosimeter 

Radiation sensitive element(s) in a holder (the holder being considered a part of the dosimeter) used for 

personnel monitoring.

1.5.4 

extremities 

The extremities are defined as the portions of the body from the elbow to the fingers and the knees to the 

toes (including the knee).

1.5.5 

processor 

A supplier of personnel dosimetry services. In relation to this document, processor is synonymous with 

laboratory.

1.5.6 

whole body

The whole body is defined as everything except extremities.

1.5.7 

PTL

The proficiency-testing laboratory.

1.5.8 

TLD

The thermo-luminescent dosimeter.

1.6 Program documentation

1.6.1 General

NVLAP assessors use NVLAP checklists to ensure that each laboratory receives an assessment comparable 

to that received by others. Checklists assist assessors in documenting the assessment to the NVLAP 

requirements found in ISO/IEC 17025, NIST Handbook 150, and this program-specific handbook. 

Checklists contain definitive statements or questions about all aspects of the NVLAP criteria for 

accreditation, and form part of the On-Site Assessment Report (see NIST Handbook 150). 

1.6.2 NVLAP General Criteria Checklist (ISO/IEC 17025:2017)

All NVLAP programs use the NVLAP General Criteria Checklist (ISO/IEC17025:2017) (formerly called 

the NIST Handbook 150 Checklist), which contains the requirements published in ISO/IEC 17025 and 

NIST Handbook 150. The checklist items are numbered to correspond to clauses 4 through 8 of ISO/IEC 

17025 and annexes A, B and E of NIST Handbook 150. 
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1.6.3 NIST Handbook 150-4 Checklist

The NIST Handbook 150-4 Checklist addresses the requirements specific to the Ionizing Radiation 

Dosimetry LAP. The checklist items are numbered to correspond to clauses 4 through 8 of NIST Handbook 

150-4. The current version of the checklist is available from the NVLAP website at 

https://www.nist.gov/nvlap. 

1.6.4 NVLAP Lab Bulletins

NVLAP Lab Bulletins are issued to laboratories and assessors, when needed, to clarify program-specific 

requirements and to provide information about program additions and changes.

2 LAP establishment, development and implementation

This clause contains no information additional to that provided in NIST Handbook 150, clause 2.

3 Accreditation process

3.1 General

3.1.1 This clause discusses the assessment and accreditation process for laboratories in the Ionizing 

Radiation Dosimetry LAP.

3.1.2 An overview of the laboratory accreditation process is provided in NIST Handbook 150, clause 3, 

and includes information pertaining to application for accreditation; on-site assessment; proficiency testing; 

accreditation decision; granting accreditation; renewal of accreditation; changes to scope of accreditation; 

monitoring visits; and suspension, denial, revocation, and voluntary termination of accreditation.

3.1.3 The assessment process consists of a NVLAP review of the application and laboratory management 

system documentation, an on-site assessment visit, and proficiency testing.

3.1.4 Proficiency testing is required before initial accreditation and every two years thereafter.

3.1.5 NVLAP management may consider a pre-assessment on-site visit to better define the laboratory's 

requested scope of accreditation. In such cases, the pre-assessment costs will be charged to the laboratory 

in addition to the actual On-Site Assessment Fee.

3.2 Management system review

3.2.1 When NVLAP receives the application, management system documents, and required procedures, 

one or more NVLAP assessors are assigned to review the management system documentation. The 

assigned assessors will review the documents to ensure they cover all aspects of the management system 

related to quality and, if followed, satisfy the requirements in ISO/IEC 17025 clauses 4 through 8, NIST 

Handbook 150-4, NIST Handbook 150 Annexes A, B and E, as applicable, and the requirements of the test 
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standards for which the laboratory seeks accreditation (i.e., ANSI/HPS N13.11, ANSI/HPS N13.32, etc.). 

Prior to conducting the on-site assessment, the NVLAP assessor may request a copy of the laboratory's 

management system documentation and cross-reference documentation that verifies that all the 

requirements of ISO/IEC 17025 and NIST Handbook 150 are addressed.

3.2.2 During the review, the NVLAP assessor may identify nonconformities and require changes to the 

management system so that it meets the requirements. A NVLAP assessor may ask for additional 

management system documents related to quality.

3.3 On-site assessment

3.3.1 When the management system review has been completed and nonconformities resolved, NVLAP 

schedules the on-site assessment. 

3.3.2 The assessment will take place at the laboratory site. The NVLAP assessor typically conducts the 

on-site assessment over a time period of three days. The assessment time may be longer depending on the 

number of dosimeter types and test categories for which a laboratory is accredited. Efforts will be made to 

minimize disruption to the normal working routines during the assessment. The NVLAP assessor will need 

time and workspace to complete assessment documentation during their time at the laboratory site.

3.3.3 The processor shall have its facilities and equipment in good working order and be ready for 

examination according to the requirements identified in this handbook, ISO/IEC 17025, NIST Handbook 

150, and the laboratory’s management system documentation.

3.3.4 The processor shall make available, at the beginning of the on-site assessment, all supporting 

technical information in a format that is conducive to a detailed review.

3.3.5 The NVLAP assessor will use the NVLAP General Criteria Checklist (ISO/IEC 17025:2017) and 

the NIST Handbook 150-4 Checklist. The checklists and the technical specifics contained in this handbook 

ensure that the assessment is complete and that all assessors cover the same items at each laboratory.

3.3.6 The activities covered during a typical on-site assessment are described below. A NVLAP assessor, 

prior to the visit, will provide a preliminary agenda, which may change due to findings observed during the 

on-site assessment. 

a) Opening meeting: The NVLAP assessor will meet with laboratory management and supervisory 

personnel, and other personnel at the discretion of the laboratory's management to explain the 

purpose of the on-site assessment and to discuss the schedule for the assessment activities. 

Information provided by the laboratory on its application form may be discussed during this 

meeting.

b) Staff interviews: The NVLAP assessor will ask the laboratory manager to assist in arranging times 

for individual interviews with laboratory staff members. The NVLAP assessor will interview staff 

members filling key positions (e.g., Laboratory Manager, Technical Director, Quality Manager, 

Authorized Representative) and staff members who have an effect on the outcome of the testing. 

The NVLAP assessor does not need to talk to all staff members; however, the NVLAP assessor 

will select staff members representing all aspects of the laboratory. These interviews are conducted 

to determine whether the staff members are properly trained, assigned, and supervised, and are 

technically competent for the tasks assigned to them.
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c) Records review: The NVLAP assessor will review laboratory documentation, including the 

management system, quality policies, equipment and maintenance records, record-keeping 

procedures, testing procedures, laboratory test records and reports, personnel competency records, 

personnel training plans and records, and safeguards for the protection of sensitive and proprietary 

information. The NVLAP assessor may request additional information to clarify issues regarding 

nonconformities or to delve more deeply into technical issues.

Processor staff shall be available to answer questions; however, the NVLAP assessor may wish to 

review the documents and records in private. The NVLAP assessor usually does not ask to remove 

any laboratory documents or records from the laboratory premises.

NVLAP assessors do not need access to employee information that may be considered sensitive or 

private such as salary, medical information, or performance reviews for work done outside the 

scope of the laboratory’s accreditation. However, this information is often stored together with 

technical information that a NVLAP assessor will need to check (e.g., job descriptions, resumes, 

and technical performance reviews). In these cases, a NVLAP assessor will work with the 

laboratory to ensure the review is performed without violating individual privacy. At the discretion 

of the laboratory, a member of the human resources department may be present during the review 

of personnel information.

d) Internal audit and management review: The NVLAP assessor will review and discuss with the 

laboratory staff the laboratory's internal audit and management review activities, which are separate 

and distinct activities. The discussion will include all aspects of those activities including the 

management system procedures, the audit findings, the results of the management review, and the 

actions taken to resolve problems identified.

e) Equipment and software: The NVLAP assessor will examine equipment and facilities and 

determine whether appropriate environmental conditions are maintained. The NVLAP assessor 

will examine hardware and software for function and appropriateness, review software validations 

and verification procedures and review the function of the dose algorithm and calculations 

performed. All equipment required to process ionizing radiation dosimeters shall be available for 

examination.

f) Demonstrations: The NVLAP assessor will observe demonstrations of dosimeter processing 

techniques and discuss them with the technical personnel to assure their understanding of the 

procedures. The NVLAP assessor may select and trace the history of one or more dosimeters from 

receipt to final issuance of the radiation dose reports of dose data transfer.

g) Proficiency testing: The NVLAP assessor will discuss all aspects of proficiency testing results 

with appropriate staff. Test methodology and records documenting the laboratory's execution of 

the testing will be reviewed and discussed. Unusual trends and outlying results will be discussed.

h) On-site assessment report: A NVLAP assessor will complete an on-site assessment report, which 

summarizes the findings. This report normally consists of the On-Site Report, the NVLAP General 

Criteria Checklist (ISO/IEC 17025:2017), and the NIST Handbook 150-4 Checklist. The first page 

of the report will be signed by the NVLAP assessor and the NVLAP Authorized Representative to 

acknowledge the discussion, but this does not necessarily indicate agreement by the laboratory. The 

assessor will submit the report through the NVLAP Interactive Web System, which will allow the 

laboratory to have access to the report documentation.
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i) Closing meeting: The NVLAP assessor will conduct a closing meeting with the laboratory 

management, supervisory personnel, and other staff members at the discretion of the laboratory's 

management to discuss findings. During the visit a NVLAP assessor will have categorized each 

finding identified as either a nonconformity or a comment. These will be discussed at the closing 

meeting. The NVLAP assessor will specifically note items that have been corrected during the onsite assessment along with any requirements for additional action. Any disagreements between the 

laboratory and a NVLAP assessor may be referred to NVLAP for resolution.

3.3.7 The processor shall address all nonconformities and provide, within 30 days from the date of the 

on-site assessment, a response to NVLAP. The laboratory shall use the NVLAP Interactive Web System 

(NIWS) for submitting the resolution of nonconformities identified during the on-site assessment.

3.3.8 The processor shall review all comments for potential improvements in the dosimetry measurement 

system.

3.4 Proficiency testing

3.4.1 Conducting proficiency testing

3.4.1.1 Each processor shall demonstrate satisfactory performance in accordance with ANSI N13.11, 

Personnel Dosimetry Performance – Criteria for Testing, and ANSI/HPS N13.32, Performance Testing of 

Extremity Dosimeters, for each dosimeter model it intends to use and in each test category for which 

accreditation is desired. Satisfactory proficiency-test results shall be demonstrated prior to initial 

accreditation and every two years thereafter.

3.4.1.2 The proficiency-test review during the on-site assessment includes:

a) The processor shall demonstrate to a NVLAP assessor that normal day-to-day processing is done 

in a manner consistent with that employed in the proficiency test.

b) If, for technical reasons, the processor needs to void a reported result in the proficiency test, all the 

corresponding objective evidence shall be documented and reviewed by the NVLAP assessor 

during the on-site assessment.

3.4.1.3 A processor has one year from the date of application to demonstrate satisfactory performance for

initial accreditation. If satisfactory performance is not demonstrated within one year or if retesting is 

required, additional test and/or administrative fees may be charged.

3.4.1.4 Proficiency testing will be administered by a proficiency-testing laboratory (PTL) that has been 

qualified by NVLAP. Specific instructions on participation in proficiency testing are included with the 

accreditation application package. Testing is conducted on a quarterly basis and is conducted over a threemonth period (test sequence) beginning the first day of January, April, July and October. After initial 

accreditation, the proficiency testing schedule for each processor is determined by NVLAP management in 

consultation with the laboratory and PTL. A participant may start a test sequence only at the beginning of 

a quarter. 
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3.4.1.5 A summary of the procedure for participation in the proficiency test follows:

a) The processor shall submit a total of 15 dosimeters of each model to be used in each category in 

which testing is desired. The dosimeters shall be submitted to the PTL in three separate groups of 

five each, one month apart. Each shipment will also require, for each model being tested, at least 

one shipping control and six extra dosimeters to be used as spares. The first shipment shall include 

two additional dosimeters of each model to be used for photos (dosimeters may have to be 

destroyed). All dosimeters will be returned when the test is complete.

b) Each shipment should arrive at the PTL at least two days prior to the first day of the month in which 

testing is to be done. Shipments arriving at the PTL after the first of the month in which testing is 

to be done may be returned unirradiated.

c) The PTL will irradiate each dosimeter to a known dose and return groups of five to the processor 

at one-month intervals.

d) The processor shall read each dosimeter and determine a dose for each category.

e) The processor shall report the determined doses to the PTL within 30 days of receipt of each 

dosimeter set. The final report of determined doses, including any changes to previously reported 

data, shall be provided to the PTL within 30 days of receipt of the third set of dosimeters.

3.4.2 Analyzing and reporting proficiency data

3.4.2.1 Reporting and analyzing the proficiency data includes:

a) At the completion of a testing quarter, the PTL will compare the processor's data with the known 

irradiation data, analyze the results, and send a detailed report containing the individual test results 

and pass/fail evaluation to the processor.

b) If, for technical reasons, the processor needs to void a reported result in the proficiency test, all the 

corresponding objective evidence shall be documented and submitted to the PTL prior to the 

completion of a testing quarter.

3.4.2.2 Copies of the report will be sent to NVLAP to be used in the evaluation of the processor and for 

use by the NVLAP assessor.

3.4.2.3 The processor shall review the proficiency testing data for potential improvements in the dosimetry 

measurement system.

3.4.3 Proficiency testing nonconformities

3.4.3.1 If a processor fails to demonstrate the expected performance for whole body dosimetry processing 

during a proficiency test, the processor shall submit additional whole-body dosimeters for a retest at the 

next available round of proficiency testing in accordance with the following requirements:
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Requirements for retest of whole body dosimeters

Failed in category

Retest in failed 

category 

Retest in failed category + 

two additional categories

Accident photons 

Protection level photons 

Betas 

Photon mixtures 

Beta/Photon mixtures 

Neutron/Photon mixtures 

3.4.3.2 A failure in extremity dosimeter categories will require a retest in each failed category.

3.4.3.3 If satisfactory proficiency test results are not received by NVLAP within six months, NVLAP will 

remove each failed dosimeter and associated category from the laboratory’s scope of accreditation. When 

the laboratory demonstrates satisfactory proficiency testing, the dosimeter(s) and category(ies) will be 

added back to the laboratory’s scope of accreditation.

3.4.3.4 In the event that a processor fails a category test more than once, fails other categories previously 

passed, or generally exhibits an erratic pattern in testing, NVLAP management will review all current and 

previous proficiency testing results and advise the processor on how to proceed. These situations will be 

handled on a case-by-case basis. Simply passing a category test after multiple attempts may not qualify as 

satisfactory proficiency.

4 General requirements

4.1 Impartiality

There are no requirements additional to those set forth in ISO/IEC 17025.

4.2 Confidentiality

There are no requirements additional to those set forth in ISO/IEC 17025.

5 Structural requirements

There are no requirements additional to those set forth in ISO/IEC 17025.
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6 Resource requirements

6.1 General

There are no requirements additional to those set forth in ISO/IEC 17025.

6.2 Personnel

6.2.1 The processor shall document the required qualifications for each staff position. The staff 

information may be kept in the official personnel folders or in separate, official folders that contain only 

the information that the NVLAP assessor need to review.

6.2.2 The processor shall maintain a list of personnel designated to fulfill NVLAP requirements 

including: Laboratory Director, NVLAP Authorized Representative, and NVLAP Approved Signatories.

6.2.3At least one of the personnel dosimetry Approved Signatories shall be experienced in applied radiation 

dosimetry and knowledgeable in the design and operation of the dosimetry system(s) currently utilized.

6.2.4 The training program and the training materials shall be updated when procedures change.

6.2.5 Staff members shall be retrained when procedures change, or when the individuals are assigned 

new responsibilities. Each staff member may receive training for assigned duties either through on-the-job 

training, formal classroom study, attendance at conferences, or another appropriate mechanism.

6.2.6 When key personnel are added to the staff, the notification to NVLAP of key personnel changes 

shall include a current resume for each new staff member.

6.2.7 For each staff member, the staff member’s immediate supervisor, or a designee appointed by the 

Laboratory Director, shall conduct annually an assessment and an observation of performance.

6.2.8 Individuals hired to perform testing activities are sometimes referred to as “subcontractors.” 

NVLAP does not make a distinction between full-time laboratory employees and individuals hired on a 

contract. NVLAP requires that the dosimetry laboratory maintain responsibility for and control of any work 

performed within its scope of accreditation. The processor shall ensure all individuals performing dosimetry 

processing activities satisfy all NVLAP requirements, irrespective of the means by which individuals are

compensated (e.g., the processor must ensure all test personnel receive proper training and are subject to 

annual performance reviews, etc.).

6.2.9 Training materials that are maintained within the processor shall be kept up-to-date.

6.3 Facilities and environmental conditions

There are no requirements additional to those set forth in ISO/IEC 17025.
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6.4 Equipment

6.4.1 The processor shall have adequate facilities and equipment to perform the type(s) of processing for

which capability is claimed. Adequate facilities and equipment shall include the following:

a) sufficient space to perform the processing;

b) proper shielding of areas from unwanted radiation;

c) necessary environmental controls;

d) radiation sources and processing equipment;

e) safety systems; and

f) properly calibrated equipment.

6.4.2 When a new dosimeter or system is to replace another, all new items shall be tested and assessed 

prior to retiring the old items from service. Depending on the timing, this may require that both systems,

the old and the new, undergo proficiency testing so that the processor maintains accreditation.

6.4.3 The processor shall maintain adequate backup equipment or systems for key processing steps to be 

used in the event of failure of primary systems or shall have provisions to utilize the services of another 

NVLAP-accredited processor in an emergency.

6.4.4 The processor shall notify NVLAP if the processor wishes to change its processing system (e.g., 

upgrade present system, entirely replace with a new system, or add a new system in addition to the current 

system). NVLAP management will advise the processor of the required proficiency testing and if an onsite assessment is necessary.

6.4.5 Any equipment used for measurement, dosimeter processing, or quality control shall be periodically 

calibrated or documented as to indicate the lack of need for periodic calibration.

6.4.6 The reference standards used and the environmental conditions at the time of calibration shall be 

documented for all calibrations.

6.4.7 Calibration records and evidence of the traceability of the reference standards used shall be made

available for inspection during the on-site assessment.

6.4.8 In addition to the information specified in ISO/IEC 17025 and NIST Handbook 150, processing 

equipment calibration records shall include the following:

a) notation of all equipment variables requiring calibration or verification;

b) range of calibration/verification;

c) resolution of the instrument and its allowable error;

d) calibration/verification date and schedule;
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e) identity of the laboratory individual or external service responsible for calibration; and

f) source of reference standard and traceability.

6.5 Metrological traceability

There are no requirements additional to those set forth in ISO/IEC 17025.

6.6 Externally provided products and services

6.6.1 The processor shall test, in accordance with standard sampling procedures, incoming supplies that 

affect the accuracy of the processing service. For example, the sampling of incoming supplies would include 

testing film and characterizing new TLD chips before initial use.

6.6.2 The processor shall use only appropriate, characterized, tested materials, including the following:

a) dosimeter materials;

b) badge holders;

c) filters;

d) chemicals; and

e) validated software.

7 Process requirements

7.1 Review of requests, tenders and contracts

There are no requirements additional to those set forth in ISO/IEC 17025.

7.2 Selection, verification and validation of methods

7.2.1 Selection and verification of methods

7.2.1.1 The processor shall develop and implement procedures covering all the technical requirements of 

this handbook.

7.2.1.2 The most recent editions of the documents listed in 1.4 shall be available as references in 

maintaining the management system.
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7.3 Sampling

There are no requirements additional to those set forth in ISO/IEC 17025.

7.4 Handling of test or calibration items

Received dosimeters shall be surveyed for radioactive contamination prior to processing.

7.5 Technical records

7.5.1 Records shall be maintained for at least three years.

7.5.2 Records shall be reviewed by the NVLAP assessor during the on-site assessment either in total or 

by selected sampling.

7.6 Evaluation of measurement uncertainty

The processor shall develop measurement uncertainty analyses for all dosimeters and radiation types for 

which it is accredited.

7.7 Ensuring the validity of results

7.7.1 ANSI/HPS N13.11 and ANSI/HPS N13.32 require that the PTL make the test irradiations on a 

specified phantom. However, the standard does not specify that a processor use such a phantom when 

making calibration irradiations. If the processor does not use a phantom, suitable factors shall be applied to 

convert from free-air calibration to on-phantom calibration.

7.7.2 The PTL will provide each participating processor with emission rate, spectrum, and backscatter 

information on the neutron source used, and calibration irradiation of a set of the processor's neutron 

dosimeters, which shall be used for ANSI/HPS N13.11 neutron/photon mixtures category.

7.7.3 Data from monitoring activities includes:

a) The processor shall have procedures for software verification and validation, including process 

control software (dosimeter handling and identification), dose algorithms, data processing (data 

analysis and reporting), and record keeping. The IEEE Standard 1012-1998, IEEE Standard for 

Software Verification and Validation Assurance Plans shall be used as a reference. In addition, 

software version control shall be included in the laboratory document control procedures for all 

software.

b) The proficiency tests are performed under controlled conditions and may not precisely reflect the 

radiation exposure monitored in the field. Algorithms used by a processor to pass proficiency 

testing may need to have special factors for specific radiation applications. However, the use of 

special workplace factors shall be done with great care, and the use of algorithms specifically 

tailored to the proficiency tests is discouraged unless they are shown to be adequate for the radiation 
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fields monitored by the laboratory. The dose algorithm used for proficiency testing shall be as 

similar as possible to the one used during normal operations.

c) Calibration/correction factors used in the dose algorithm(s) can be developed from calibration 

irradiations provided by the PTL or other laboratories, such as in the case of neutrons. The 

algorithm shall be available to the assessor for review in order to determine appropriateness and 

verification of calculations and function.

7.8 Reporting of results

7.8.1 General

There are no requirements additional to those set forth in ISO/IEC 17025.

7.8.2 Common requirements for reports (test, calibration or sampling)

The processor shall meet contract requirements for reporting dose and the requirements specified by 

appropriate regulatory authorities. The NRC requirements for reporting dose are specified in the Code of

Federal Regulations, 10 CFR Part 20, Standards for Protection Against Radiation.

7.8.3 Specific requirements for test reports

7.8.3.1 The final report from processors who provide dosimetry services to internal clients (i.e., dosimeters 

are issued to workers under the same organization, such as a utility company with a dosimetry processing 

division) shall include the following:

a) facility name and/or location where dosimeter was issued/worn;

b) pertinent dates (date dosimeters irradiated, date dosimeters processed, report date, etc.);

c) description or identification of each dosimeter and/or elements;

d) explanation of any deviation from the procedures affecting the reported results;

e) identification of anomalies;

f) well defined data resulting from the processing; and

g) name of NVLAP signatory who reviewed, validated, and authorized the individual's dose 

measurement.

7.8.3.2 The final report from processors who provide dosimetry services to external clients shall include 

the following:

a) name and address of processor and client;

b) pertinent dates;

c) description or identification of each dosimeter and/or elements;
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d) "Occupational Radiation Exposure Report" or a similar title;

e) explanation of any deviation from the procedures affecting the reported results;

f) identification of anomalies;

g) adequately defined data resulting from the processing; and

h) signature or reference to person having technical responsibility.

7.9 Complaints

There are no requirements additional to those set forth in ISO/IEC 17025.

7.10 Nonconforming work

There are no requirements additional to those set forth in ISO/IEC 17025.

7.11 Control of data and information management

There are no requirements additional to those set forth in ISO/IEC 17025.

8 Management system requirements

8.1 Options

There are no requirements additional to those set forth in ISO/IEC 17025.

8.2 Management system documentation

8.2.1 If the processor uses a computer-based documentation system, the processor should consider the 

ease of usability by the staff. The processor shall ensure that the requirements of ISO/IEC 17025 are met 

so that staff is knowledgeable of the online documentation system and can readily retrieve appropriate 

information.

8.2.2 The processor shall have a method for identifying dosimeters that the processor has received for

testing. This identification can be used for verification of the test report and tracking the progress of the test 

item from receipt until the test report is sent to the client.

8.3 Control of management system documents

8.3.1 The controlled version of the laboratory management system documentation may be paper-based 

or computer-based. Version control shall be maintained in either case.
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8.3.2 The processor shall create a cross-reference document allowing the laboratory and the assessors to 

verify that all requirements of ISO/IEC 17025 and NIST Handbook 150 Annexes A, B and E, as applicable,

are addressed in the management system documentation.

8.3.3 A general reference text on statistics shall be available in the laboratory.

8.3.4 The processor shall have copies of applicable referenced standards, practices and procedures.

8.3.5 In addition to the information specified in ISO/IEC 17025, the quality management system and/or 

supporting management procedures shall include the following:

a) processing facilities and scope of services offered;

b) processing equipment inventory including radiation sources used for calibration;

c) processing equipment calibration, verification, and maintenance practices;

d) dosimeter models and design specifications;

e) acceptance criteria for dosimeter holders and materials;

f) procedures for handling and storing sensitive components and materials;

g) assembly/disassembly techniques for all dosimeter models used;

h) procedures for periodic checks on in-service dosimeters;

i) dosimeter calibration techniques and procedures;

j) identification and tracking of dosimeters;

k) handling, control and storage of in-service dosimeters;

l) actions concerning damaged dosimeters;

m) instructions to operate all processing equipment, including any operational checks;

n) data handling and reporting;

o) actions when test data indicate a possible problem exists; and

p) policy for utilizing subcontractors.

8.4 Control of records

There are no requirements additional to those set forth in ISO/IEC 17025.
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8.5 Actions to address risks and opportunities

There are no requirements additional to those set forth in ISO/IEC 17025.

8.6 Improvement

There are no requirements additional to those set forth in ISO/IEC 17025.

8.7 Corrective actions

There are no requirements additional to those set forth in ISO/IEC 17025.

8.8 Internal audits

8.8.1 The most recent internal audit report shall be available for review during NVLAP on-site 

assessments.

8.8.2 Previous internal audit reports, as far as three years back, shall be available for review if requested 

by the NVLAP assessor.

8.8.3 The internal audit shall cover compliance with NVLAP, laboratory management system, 

regulatory, and contractual requirements.

8.8.4 The processor shall perform at least one complete internal audit of its management system prior to 

the first on-site assessment. The records will be reviewed before or during the on-site assessment visit.

8.8.5 The processor shall perform at least one complete internal audit of its management system annually.

8.9 Management reviews

8.9.1 Periodic reviews of the management system shall reflect adherence to NVLAP requirements and 

the laboratory's quality objectives.

8.9.2 The periodic management reviews shall reflect positive aspects of the management system as well 

as nonconformities.

8.9.3 The most recent management review report shall be available for review during NVLAP on-site 

assessments.

8.9.4 Previous management review reports, as far as three years back, shall be available for review if 

requested by the NVLAP assessor.

8.9.5 The processor shall perform at least one complete management review prior to the first on-site 

assessment. The records will be reviewed before or during the on-site assessment visit.

8.9.6 The processor shall perform at least one complete management review annually.
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9 Additional requirements

There are no additional requirements beyond ISO/IEC 17025, NIST Handbook 150 and its associated 

normative annexes, and any other normative references previously cited in this handbook.