Draft Report 

NATIONAL INSTITUTE FOR 

OCCUPATIONAL SAFETY AND HEALTH 

ADVISORY BOARD ON RADIATION AND WORKER HEALTH 

TASK 3: REVIEW OF NIOSH/ORAUT PROCEDURES AND METHODS 

USED FOR DOSE RECONSTRUCTION

Review of ORAUT-OTIB-0066 

Calculation of Dose from Intakes of Special Tritium Compounds

Contract No. 200-2004-03805 

SCA-TR-TASK3-0010, Revision 0 

Prepared by 

S. Cohen & Associates 

1608 Spring Hill Road, Suite 400 

Vienna, VA 22182 

Saliant, Inc. 

5579 Catholic Church Road 

Jefferson, Maryland 21755

November 2008 

Disclaimer

This document is made available in accordance with the unanimous desire of the Advisory Board on 

Radiation and Worker Health (ABRWH) to maintain all possible openness in its deliberations. However, 

the ABRWH and its contractor, SC&A, caution the reader that at the time of its release, this report is predecisional and has not been reviewed by the Board for factual accuracy or applicability within the 

requirements of 42 CFR 82. This implies that once reviewed by the ABRWH, the Board’s position may 

differ from the report’s conclusions. Thus, the reader should be cautioned that this report is for 

information only and that premature interpretations regarding its conclusions are unwarranted. 
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Document No. 

SCA-TR-TASK3-0010 

Effective Date: 

 Draft – November 25, 2008 

S. Cohen & Associates: 

Technical Support for the Advisory Board on 

Radiation and Worker Health Review of NIOSH 

Dose Reconstruction Program Revision No: 

 0 – Draft 

Review of ORAUT-OTIB-0066: 

Calculation of Dose From Intakes of Special 

Tritium Compounds 

Task Manager: 

_____________________ Date: ____________ 

Stephen L. Ostrow, PhD 

Project Manager: 

_____________________ Date: ____________ 

John Mauro, PhD, CHP 

Supersedes: 

N/A 
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NOTICE:

TABLE OF CONTENTS 

Executive Summary.........................................................................................................................4 

Introduction..........................................................................................................................4 

Review Methodology...........................................................................................................4 

Summary of Findings and Comments..................................................................................5 

1.0 Summary of ORAUT-OTIB-0066 Methodology ................................................................7 

1.1 ORAUT-OTIB-0066 Modeling ...............................................................................7 

1.2 ORAUT-OTIB-0066 Dose Calculations..................................................................8 

1.3 ORAUT-OTIB-0066 Recommendations...............................................................10 

2.0 SC&A Assessment of ORAUT-OTIB-0066......................................................................11 

2.1 Introduction............................................................................................................11 

2.2 Review of Data Available in the Open Literature .................................................11 

2.2.1 Tritiated Water (HTO)...............................................................................11 

2.2.2 Organically Bound Tritium (OBT)............................................................11 

2.2.3 Metal Tritides (SMT).................................................................................12 

2.3 Workplace Characterization...................................................................................12 

2.4 Dose Assessment Based on Available ICRP Models............................................15 

2.5 SC&A Comments..................................................................................................16 

2.5.1 Agreement with ORAUT-OTIB-0066.......................................................16 

2.5.2 Disagreement with ORAUT-OTIB-0066 ..................................................16 

2.5.3 SC&A Recommendations..........................................................................20 

3.0 Procedure Checklist ...........................................................................................................21 

4.0 References..........................................................................................................................25 
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EXECUTIVE SUMMARY 

INTRODUCTION 

This report presents a technical review of Calculation of Dose from Intakes of Special Tritium 

Compounds, ORAUT-OTIB-0066, Rev. 0, April 26, 2007 (ORAUT 2007, hereafter referred to 

as “the OTIB” or “OTIB-0066”). The review is limited to those aspects of this Oak Ridge 

Associated Universities Team Technical Information Bulletin (OTIB) judged by SC&A to be 

potentially significant to dose reconstruction, and is not a line-by-line check of data sources and 

calculational results. This review also considered the availability of information and data to 

effectively implement this procedure during individual dose reconstructions. 

The most commonly encountered exposure pathway to tritium in dose assessments is when the 

tritium is in the form of tritiated water (HTO), in which a tritium (H-3) atom replaces one of the 

light hydrogen (H-1) atoms. NIOSH presents its methodology to determine the dose from the 

intake of tritiated water in ORAUT-OTIB-0011, Tritium Calculated and Missed Dose Estimates

(ORAUT 2004) and recapitulates it in OTIB-0066. Section 2.0 of OTIB-0011 states the 

following: 

The model used for assessing effective dose (ED) from intakes of tritiated water is 

that of the International Commission on Radiological Protection (ICRP). The 

current model is described in detail in ICRP Publication 56 [ICRP 1989] with the 

current dose conversion factor published in ICRP Publication 68 [ICRP 1994b]. 

Tritiated water is assumed to be completely and instantaneously absorbed into the 

systemic circulation whether taken in by inhalation, ingestion, or absorption 

through the intact skin. In a relatively short time, tritiated water equilibrates with 

the body water and thereafter the concentration in all body fluids, including 

urine, is assumed to be equal. For this reason, urine measurements of tritium are 

considered a direct measurement of the concentration of tritium in body water. 

Whatever the merits of the guidance provided by OTIB-0011, however, it does not, provide 

guidance for assessing dose due to intake of other tritium compounds that may be encountered in 

certain circumstances; these situations are treated in OTIB-0066, which “provide[s] guidance on 

how to use urine bioassay data to calculate the best estimates of the annual organ doses for 

intakes of bound to organic compounds (organically bound tritium - OBT) and tritium in a metal 

matrix (stable metal tritide - SMT)” (ORAUT 2007, pg. 5). 

REVIEW METHODOLOGY 

SC&A reviewed ORAUT-OTIB-0066 (ORAUT 2007) in a systematic manner, following the 

OTIB’s organization and the guidance of SC&A’s review procedure, A Protocol for the Review 

of Procedures and Methods Employed by NIOSH for Dose Reconstruction (SC&A 2004). 

Section 1 of this review report summarizes the methodology NIOSH presents in the OTIB 

sections, Section 2 presents SC&A’s assessment and recommendations, and Section 3 contains a 
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checklist taken from SC&A 2004. The checklist has sections concerned with the following 

issues: 

 The degree to which the procedure supports a process that is expeditious and timely for 

dose reconstruction 

 Whether the procedure provides adequate guidance to be efficient in instances where a 

more detailed approach to dose reconstruction would not affect the outcome 

 The extent to which the procedure accounts for all potential exposures, and to ensure that 

resultant doses are complete and based on adequate data 

 Whether the procedure provides a consistent approach to dose reconstruction, regardless 

of claimant’s exposures by time and employment locations 

 Whether the procedure is fair and gives the benefit of the doubt to the claimant 

 Whether the procedure adequately accounts for the uncertainty of dose estimates 

 Whether the procedure strikes a balance between technical precision and process 

efficiency 

This review also discusses the feasibility of implementing the procedure, since the process 

developed in OTIB-0066 serves as a supplement to dose reconstruction guidelines provided in 

individual site profiles and special exposure cohort (SEC) evaluation reports. 

SUMMARY OF FINDINGS AND COMMENTS 

SC&A’s review of the OTIB is presented in Section 2; the review produced six Comments. 

SC&A divided these Comments into four Findings and two Observations, where the former are 

felt important by SC&A and should be addressed by NIOSH, while the latter comprise items of 

agreement and support for the OTIB. 

Findings Observations

Comments

Table 1 collects the Comments, notes where they are found in this document, and indicates 

whether each is a Finding or an Observation. 

 
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NOTICE:

Table 1: Comment Summaries 

Comment 

Number 

Finding 

Number Summary Description 

1 

(Sect 2.4.1) 

O (a) Issue 1: SC&A has found that ORAUT-OTIB-0066 is clear and consistent 

with International Commission on Radiological Protection (ICRP) 

Publications 56 (ICRP1989) and 67 (ICRP 1993), ORAUT-OTIB-0011, and 

open literature (Balonov et al. 1984, 1995; Cheng et al. 1997, 1999, 2002a, 

2002b; Inkret et al. 2001; Zhou and Cheng 2003; Hodgson et al. 2004; and 

Zhou and Cheng 2004). 

2 

(Sect 2.4.1) 

O Issue 2: The procedure provides adequate and valid technical information 

and guidance to evaluate the dose due to intake of HTO, OBT, and SMT, 

applying the ICRP models in IMBA. 

3 

(Sect 2.4.2) 

1 Issue 3: The recommendation given in ORAUT-OTIB-0066 to assess dose 

due to intake of OBT is not claimant favorable. The OTIB recommends the 

use of the methodology given in ORAUT-OTIB-0011 to calculate doses from 

intakes of OBT to all organs and tissues. The dose coefficient for OBT given 

in ICRP Publication 78 (ICRP 1997), which is 1.52 × 10-7 mrem/pCi (see 

Table 2); the one derived applying the biokinetic model for OBT (ICRP 1989; 

ICRP 1993; ICRP 1995; and ICRP 1997) using the AIDE computer code, 

which is 1.52 × 10-7 mrem/pCi (see Table 2); and the one derived using the 

methodology given in ORAUT-OTIB-0066 (ORAUT 2007), which is also 

1.52 × 10-7 mrem/pCi (see Table 1), are 1.4 times higher than the one 

obtained applying the methodology given in ORAUT-OTIB-0011 (ORAUT 

2004), which is 1.08 × 10-7 mrem/pCi. 

 

4 2 Issue 4: Bounding techniques proposed in OTIB-0066 cannot be effectively 

developed and applied without some basic understanding of the special 

tritium compounds handled, the quantities of material, the locations and time 

periods of potential exposure, and the physical behaviors of tritium 

compounds in the environment (e.g., conversion to HTO, formation of rust) 

to correctly characterize tritium exposure. 

5 3 Issue 5: OTIB-0066 does not ensure that resultant doses are based on 

adequate monitoring data. 

6 4 Issue 6: The procedure provides no guidance on how to distinguish between 

intakes of STCs, elemental tritium, and/or tritiated water which occur 

simultaneously or overlap. 

Note: (a) “O” denotes observation. 
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1.0 SUMMARY OF ORAUT-OTIB-0066 METHODOLOGY 

The OTIB’s development of the guidance given to dose reconstructors in estimating doses from 

exposure to tritium-containing compounds proceeds through a number of steps, which were 

examined by SC&A to determine whether they are based on accepted, sound scientific or 

engineering practice; reasonable; clearly stated; adequately documented; and claimant favorable. 

The following summarizes the OTIB section-by-section for convenience. 

1.1 ORAUT-OTIB-0066 MODELING 

OTIB-0066 treats three scenarios of tritium intake into the 

body and subsequent exposure, where the tritium taken in is 

either in the form of tritiated water (HTO), a stable metal 

tritide (SMT), or organically bound tritium (OBT). Section 

3.0 discusses the biokinetic models employed by NIOSH in 

these cases. Figures 3-1, 3-2, and 3-3 of the OTIB display 

biokinetic block diagrams for the three situations 

respectively. The block diagrams are reproduced here and 

the models will be briefly described. It should be noted 

that in all three biokinetic models the water compartment 

(with a biological half life of about 10 days) feeds with a 

47% split directly into the bladder for elimination as urine 

and with a 53% split (essentially, tritium in the blood) into 

a compartment marked “other.” The latter represents, in 

effect, a feedback pathway to the transfer compartment for 

another pass through the body. 

Tritiated Water - HTO

Figure 3-1 of the OTIB shows the compartmentalized NIOSH 

biokinetic model for tritiated water, which is implemented in 

IMBA (Interactive Modules for Bioassay Analysis) software. It 

should be noted, that the model includes a compartment for 

organically bound tritium (OBT), which “represents tritium that 

is incorporated into carbon compounds and is retained with a 

half-life of 40 d as described in the ICRP carbon biokinetic 

model [ICRP 1993]” (ORAUT 2007, pg. 5). The model 

assumes that 3% of the HTO that is taken in goes to the OBT 

compartment, 97% remains in the water compartment, and all 

of the tritium in the OBT compartment is eventually excreted 

from the bladder as HTO. 

Stable Metal Tritide - SMT 

Figure 3-2 of the OTIB incorporates a lung model to reflect 

inhalation of stable metal tritides, which are certain metallic 

compounds (containing, for example, titanium, hafnium, 
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palladium, lithium, uranium, or zirconium) that can bind and retain tritium interstitially in their 

crystalline structures (in fact, various metal hydrides have been considered to store hydrogen fuel 

for hydrogen-powered automobiles). An SMT may be inhaled into the lungs as an aerosol and 

slowly released there “as the particle of the SMT dissolves and the tritium diffuses out of the 

particle” (ORAUT 2007, pg. 6). The tritium is assumed to displace hydrogen in water molecules 

and form HTO, which then can be treated by the HTO biokinetic model. “The SMT biokinetic 

model shown in Figure 3-2 is therefore the HTO biokinetic model with an ICRP Publication 66 

Human Respiratory Track Model feed compartment [ICRP 1994a]” (ORAUT 2007, pg. 6). As 

in the HTO model, it is assumed that 3% of the HTO goes to the OBT compartment. 

Solubility of the SMT in the lungs depends on the type, size, 

and shape of the metal particles. The OTIB states that, “of 

the SMTs discussed in the literature, titanium and zirconium 

appear to be best described as type M, whereas hafnium is 

best described as type S...Other tritides that consist of more 

reactive metals such as lithium and uranium are expected to 

be best described as type F” (ORAUT 2007, pp. 6–7). 

Organically Bound Tritium - OBT

The biokinetic model for HTO (illustrated in OTIB 

Figure 3-1) contains an OBT compartment, where some 

(assumed 3%) of tritium in the HTO taken in by the person 

enters into carbon compounds in the body. In the biokinetic 

models for OBT (OTIB Figure 3-3), however, the tritium 

enters the body already in the form of a carbon compound. 

The OBT model follows ICRP guidance and “assumes that 

50% of the OBT compounds taken into the body are 

immediately converted to HTO and the other 50% remain 

OBT” (ORAUT 2007, pg. 7). 

1.2 ORAUT-OTIB-0066 DOSE CALCULATIONS 

Section 4.0 of the OTIB discusses how doses are calculated by applying the three biokinetic 

models and estimates the accuracy of the methodologies. It begins by stating that, “intakes of 

HTO are usually evaluated using an isotopic dilution technique..., which is based on the 

following assumptions:” 

1. HTO is metabolized like H2O. 

2. The metabolic space of H2O is the 42 L of body water. 

3. The concentration of HTO in the urine is the same as the concentration of 

HTO in the body water (pp. 8–9) 

Hence, under these assumptions, “the quantity of HTO in the body at any given time is simply 

the concentration of HTO in the urine times the volume of body water, and the dose to the soft 

tissues of the body is proportional to the area under the excretion curve” (ORAUT 2007, pg. 9). 
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That area can be calculated in several different ways. The OTIB states that “the standard method 

for calculating the dose from intakes of tritiated water given in ORAUT-OTIB-0011, Tritium 

Calculated and Missed Dose Estimates (ORAUT 2004), uses three different techniques to 

calculate the area under the excretion curve” (ORAUT 2007, pg. 9). These techniques are called 

Type 1, Type 2, and Type 3. 

A Type 1 area calculation is a linear approximation between two urinary excretion measurements 

when they are taken less than 40 days apart. A Type 2 area calculation uses an exponential 

extrapolation from one measurement point to the next, when they are more than 40 days apart. 

Application of the Type 2 method presumes that the fact that the two measurements were more 

than 40 days apart means that the person did not work with tritium; a Type 2 calculation gives a 

lower area (dose) than a Type 1 calculation. A Type 3 calculation extrapolates exponentially to 

infinity (in time) after the last measurement. 

OTIB-0066 notes that adding the OBT compartment into the biokinetic model (shown in OTIB 

Figure 3-1) does not conform to assumption 2 listed above, since the tritium in the OBT 

compartment is not uniformly distributed in the body. The error, potentially resulting in a dose 

underestimation, is slight, however, since it is assumed that only 3% of the HTO goes into the 

OBT compartment; OTIB-0011 adjusts the dose conversion factor upward, rendering dose 

calculations to systemic organs conservative (an overestimate) for Type 1 area calculations. 

OTIB-066 extends its claim of conservatism for Type 1 calculations to the case where SMTs are 

present in the lungs, “because SMTs in the lungs are essentially a longer term feed compartment 

for HTO going to the systemic organs” (ORAUT 2007, pg. 9). However, the same is not true for 

intakes of OBT compounds, which are not uniformly distributed in the body-water space. In this 

case, “a Type 1 calculation underestimates systemic dose by approximately 30%” (ORAUT 

2007, pp. 9–10). The OTIB maintains that this may not be very significant in practice as many 

“occupational sources of OBT (e.g., pump oil) tend to have a significant OBT component” 

(ORAUT 2007, pg. 10). 

Such a claimant-favorable conclusion, however, cannot be reached for Types 2 and 3 

calculations of the area under a tritium excretion curve, which assume a 10-day half-life, 

although “portions of the urinary excretion curves have half-lives that are significantly longer 

than 10 d” (ORAUT 2007, pg. 10). In these cases, calculated doses to systemic organs from 

OBT and SMT compounds will be underestimated. The OTIB states: “As an example of a 

worst-case scenario, if a single urine result is evaluated using a Type 3 calculation (i.e., assuming 

it is HTO) and is in fact from an intake of Type S tritide, the dose for the tail (not the total dose) 

will be underestimated by a factor of about 6” (ORAUT 2007, pg. 10). 

The degree to which the total systemic dose is underestimated for OBT and SMT 

depends on the fraction of the systemic dose from Type 2 and 3 calculations. For 

example, if the entire systemic dose up to the time of diagnosis is determined with 

Type 1 calculations, the systemic dose can be taken to be accurate regardless of 

the material. On the other hand, if most of the systemic dose is determined with 

Type 2 and 3 calculations and the material is Type S SMT, the systemic dose 

could be significantly underestimated (ORAUT 2007, pg. 10). 
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NOTICE:

The OTIB cautions that the dose to the lung can be seriously underestimated (by several orders 

of magnitude) if ORAUT-OTIB-0011 methodologies are applied. Table 4.1 of OTIB-0066 

(reproduced here as Table 2) presents calculated doses for several cases for an assumed 1-pCi 

acute intake of tritium compounds (these doses per unit source are sometimes referred to as dose 

coefficients). It is seen that while the OTIB-0011-calculated results agree fairly well with the 

IMBA soft tissue dose model and the IMBA lung dose model for HTO and OBT intake cases, 

they are very much lower than the corresponding IMBA lung dose results for SMT intakes. 

Table 2. Comparison of Calculated Doses for a 1-pCi Acute Intake of 

Tritium Compounds (mrem) 

ORAUT-OTIB-11 

Soft tissue dose 

IMBA 

Soft tissue dose 

IMBA 

Lung dose 

Type S SMT 6.58E-10 6.30E-10 3.86E-06 

Type M SMT 7.28E-09 6.93E-09 5.52E-07 

HTO 7.11E-08 6.76E-08 6.76E-08 

OBT 1.08E-07 1.52E-07 1.52E-07 

 Source: ORAUT 2007, Table 4.1 

1.3 ORAUT-OTIB-0066 RECOMMENDATIONS 

Section 5.0 of the OTIB presents recommendations for determining doses from tritium intakes 

via different pathways; these are summarized as: 

(1) “Selection of the appropriate tritium compound in an intake evaluation must usually be 

based on process knowledge of the source terms in the workplace.” 

(2) “The methodology in ORAUT-OTIB-0011 (ORAUT 2004) can be used without 

modification to calculate doses from intakes of HTO and OBT to all organs and tissues.” 

(3) The OTIB-0011 methodology can be used to calculate systemic doses from intakes of 

SMT “if the majority of the dose is calculated with the Type 1 method... On the other 

hand, if the majority of the systemic dose is calculated with Type 2 or 3 methods, IMBA 

should be used to calculate the dose.” 

(4) “If the observed urinary excretion of tritium is deemed to be the result of intakes of SMT 

and the dose to the lung or gastrointestinal (GI) tract is needed, the urinary excretion data 

must be evaluated with IMBA in the same fashion as any other radionuclide.” 

(5) “If the metal substrate of the SMT is not known, type S solubility should be assumed.” 
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2.0 SC&A ASSESSMENT OF ORAUT-OTIB-0066 

2.1 INTRODUCTION 

ORAUT-OTIB-0066 recommends that the dose reconstructor assume solubility classes of 

Type M or S for metal tritides (SMT), depending on the compound. This guidance is consistent 

with recent data available in the literature (Balonov et al. 1984, 1995; Cheng et al. 1997, 1999; 

2002a, 2002b; Inkret et al. 2001; Zhou and Cheng 2003; Hodgson et al. 2004; Zhou and Cheng 

2004).

The OTIB provides guidance to assess the dose applying ICRP systemic models and lung 

retention parameters for HTO, OBT, and SMT, using the IMBA computer code. Section 4.0 

calculates and compares doses obtained using its approach to that determined using the ORAUTOTIB-0011 model (ORAUT 2004), which was developed to be applied to doses resulting from 

intake of HTO. Table 4.1 of OTIB-0066 (reproduced here as Table 1) presents calculated doses 

for an assumed 1-pCi acute intake of tritium compounds. The OTIB recommends the use of the 

methodology in ORAUT-OTIB-0011 to calculate doses from intakes of HTO and OBT to all 

organs and tissues and for systemic organ doses due to intake of SMT. However, the dose to the 

lung or gastrointestinal (GI) tract must be evaluated with IMBA as for any other radionuclide. 

2.2 REVIEW OF DATA AVAILABLE IN THE OPEN LITERATURE 

2.2.1 Tritiated Water (HTO) 

ICRP Publications 56, 67, 71, and 78 (ICRP 1989; ICRP 1993; ICRP 1995 and ICRP 1997) 

assume that for tritiated water there is 100% deposition in the respiratory tract, with 

instantaneous (Type V) absorption over the total body. Those publications recommend a twocomponent model for predicting the behavior of tritium that enters the human body as HTO, in 

which 97% of the tritium is assumed to be eliminated, with a biological half-life of ten days and 

that 3% became organically bound and is eliminated with a biological half-life of 40 days. 

However, it is recognized that a small fraction of the activity might be retained for much longer 

periods. This third compartment would represent tritium incorporated into structural or other 

tissue components with very slow turnover. The second compartment, plus any possible third 

compartment, is considered likely to contribute about 10% to the committed dose (ICRP 1989). 

2.2.2 Organically Bound Tritium (OBT) 

ICRP Publications 56, 67, 71 and 78 (ICRP 1989; ICRP 1993; ICRP 1995 and ICRP 1997) 

assume for organically bound tritium (OBT), 100% deposition in the respiratory tract, with 

instantaneous (Type V) absorption. Those publications recommend a default model for all 

unknown compounds containing OBT, which assumes that 50% of the OBT entering the 

systemic compartment would be metabolized to HTO and lost with a biological half-life of ten 

days, and that the remaining 50% would bond with carbon and be removed with a biological 

half-life of 40 days. The concentration in urine is assumed to be the same as in total body water. 

Urinary excretion will not result in a significant additional dose to the bladder wall, which is 

assumed to receive the same dose as other tissues. 
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2.2.3 Metal Tritides (SMT) 

ICRP Publication 71 (ICRP 1995) states that: 

 (91) Tritium could be released to the environment in particulate form, and 

studies of the solubility of solid tritiated compounds have been conducted. For 

example, the results of an in vitro study of the dissolution of 1 μm (count median 

diameter) titanium tritide powder in serum ultrafiltrate were consistent with the 

assignment to Type M (Cheng et al., 1994). Preliminary results following 

intratracheal instillation of titanium tritide into rats indicate that the dissolution 

rate is similar to that observed in vitro (Cheng et al., 1995). It is assumed that for 

inhalation of inorganic particulate material, the biokinetics of tritium absorbed 

into body fluids follow that of HTO. 

There are additional studies, in the recent literature, showing that the dissolution of solid tritiated 

compounds follow the same behavior as Type M and Type S classes of solubility described in 

ICRP Publication 66 (ICRP 1994a). 

Animal studies have shown that titanium tritide presents a slow lung clearance, and hence should 

be assigned to ICRP Publication 30 Class Y. It is suggested that titanium tritide should be 

assigned to Types M or Type S (Balonov et al. 1984, 1995; Cheng et al. 1997, 1999). The lung 

retention parameters for zirconium tritide are consistent with assignment to Type M and Type S 

in animals (Zhou and Cheng 2004). For carbon tritide, studies have suggested consistency with 

ICRP Type M and Type S classes of solubility (Cheng et al. 2002a, Hodgson et al. 2004). 

Experiments with animals have shown that hafnium tritide is consistent with ICRP Type M and 

Type S classes of solubility (Zhou and Cheng 2003; Inkret et al. 2001; Cheng et al. 2002b). In 

summary, the published studies on tritides suggest that the lung retention parameters are similar 

to the ICRP Type M and S compounds. 

2.3 WORKPLACE CHARACTERIZATION 

The Department of Energy (DOE) and its predecessor agencies have undertaken missions 

involving work with hazardous and/or exotic materials and agents, and byproducts of their 

production, storage, and use. Included in these exotic materials are metal tritides (MTs) and 

organically-bound tritium (OBT), referred to collectively as special tritium compounds (STCs) 

(DOE 2004). Sites identified as handling STCs directly include, but are not limited to, the 

Mound Plant, Lawrence Livermore National Laboratory (LLNL), Los Alamos National 

Laboratory (LANL), the Pinellas Plant, Sandia National Laboratory (SNL), and Oak Ridge 

National Laboratory (ORNL). Other sites came in contact with STCs as a byproduct of the 

work they conducted on components received from these facilities. Other STCs have been 

introduced to sites as a byproduct of handling large quantities of tritium gas and tritiated water, 

and its subsequent absorption into materials (e.g., rust, tritiated oil, tritiated dust, etc.). STCs 

differ from tritium oxide and elemental tritium (HT) in their physical, chemical, and 

radiological properties, which may make their detection, characterization, and subsequent 

assessment of exposure effects difficult. 
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Examples of processes where STCs may create a potential for exposure include (DOE 2004): 

 Tritium targets for neutron generators 

 Reactor operations 

 Fusion experiments 

 Extrication of tritium from fuel elements 

 Isotope separation 

 Storage of tritium 

 Operations with tritium-labeled compounds 

 Waste treatment and storage 

 Decontamination and decommissioning activities 

 Weapons testing 

There are any number of locations where these materials may be encountered, such as glove 

boxes, fume hoods, ventilation systems, weapons components, and fuel storage basins. 

STCs are categorized by physical form (e.g., liquid/vapor, particulate, or large solid form) and by 

solubility (e.g., insoluble, partially soluble, soluble). At some facilities, they refer to metal 

tritides as stable or unstable, which is a measure of how easily the tritium is released from the 

metal in air or aqueous material. Insoluble metal tritides (i.e., stable metal tritides) include 

hafnium, titanium, europium, and zirconium tritide. Soluble forms of MTs include uranium, 

lithium, and palladium tritide (DOE 1994, DOE 2004). While providing examples of soluble 

and insoluble metal tritides, this list is not inclusive of the metal tritides handled by the DOE 

complex. Tritiated metals can also be produced as a byproduct of handling large amounts of HT 

or HTO. 

Tritium as HT or HTO will readily adsorb onto the surface of most metals (e.g., 

stainless steel, copper, aluminum), plastics, and rubbers. The tritium will remain 

fairly close to the surface unless the metal is heated to high temperatures. At 

room temperature, permeation into these metals is extremely slow. (DOE 1994) 

Furthermore, 

 Metal surfaces exposed to high pressures of HT or HTO for extended periods, 

especially at high temperatures, may allow enough penetration to cause 

structural damage to metal. (DOE 1994) 

Organically Bound Tritium (OBT) is formed when tritium forms a chemical bound with organic 

materials, typically by creating carbon-tritium bonds. Under some conditions, this is done 

intentionally, such as radioactive labeling of biological molecules, and, in other cases, it is a 

byproduct of organics adsorbing elemental tritium or tritium oxide. Solid particulate OBTs are 

largely formed by incidental contamination of environmental dust and other materials found in 

most tritium contamination areas. DOE-HDBK-1079-94, Primer on Tritium Safe Handling 

Practices (DOE 1994), describes the interaction of tritium with hydrogenous materials. 
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If adsorbed onto hydrogenous material, the tritium will easily permeate into the 

material. The HTO will move much more rapidly into the bulk material than will 

HT. The permeation rate varies with the type of material and is accelerated by 

increasing the temperature. As a result of this movement, plastics and rubbers 

exposed to tritium (especially as HTO) are readily contaminated deep into the 

bulk material and are impossible to decontaminate completely. 

Insoluble OBTs include tritiated pump oil, dust, rust, pump oil droplets, tritiated flyash, and 

tritiated nylon. Soluble OBTs include tritiated solvents and methane (DOE 2004). Particulates 

can be generated during dispersal mechanisms from material such as plastic, nylon, organic dust, 

or large molecule components of OBT oil. Insoluble OBTs present the same challenges in 

detection and measurement that other insoluble tritiated particulates present. 

Because of the low energy beta particle emitted by tritium, area monitoring efforts are limited to 

surface contamination and airborne radioactivity monitoring. Surface contamination for tritium 

is determined by taking either a wet or dry smear and counting it in a liquid scintillation counting 

(LSC) system. Although LSC is effective for detecting the presence of tritium, this technique 

does not differentiate between types of tritium. Stable metal tritides present a unique challenge 

when attempting to monitor for surface and skin contamination. Since these materials are in 

particulate form, many of the tritium atoms associated with the particle are internal to the surface 

of the particle. As a result, the counting technique will show a tritium activity that is too low, 

since the beta particle from tritium within the metal tritide particle cannot escape the particle. As 

the tritium is released from the metal, the concentration of tritium in the scintillation cocktail will 

increase, and thus the concentration will appear to increase. To date, there is not a simple and 

reliable method for identifying STCs. Some work has been conducted using an Energy 

Dispersive X-ray/Scanning Electron Microscopy technique; however, this method has only been 

applied since the 1990s. The method is used to establish the presence, size and shape of 

insoluble tritium particulates, but does not provide information on the tritium concentrations. 

Typical continuous air monitoring techniques used flow-through ionization chambers as the 

major monitoring technique for identifying tritium in air. These instruments can measure tritium 

in its elemental form (HT), oxide form (HTO), or any other gaseous compound form (tritiated 

methane, ammonia, etc.). However, filters and electronic precipitators are often used in 

conjunction with these air monitoring systems to prevent particulates from entering the 

ionization chamber and thus being detected. 

While soluble STCs can be detected via urine bioassay, insoluble STCs present substantial 

bioassay challenges. Insoluble STCs can be difficult to detect in urine because of low 

dissolution rates of some compounds. For example, studies reported by Cheng, et al. (Cheng 

2002b) point out that for hafnium tritide particles in simulated lung fluids, less than 1% of the 

tritium was dissolved after 215 days, and the long-term dissolution half-time was 4.28×105

 days. 

Dissolution rates are also size and shape dependent, and although dissolution rate data are 

available for several materials, these data do not include all the possible combinations of 

materials and particle sizes which might be encountered in the workplace. In vivo analysis is not 

a viable means of personnel monitoring, because the low-energy beta particle cannot penetrate 

through the body to the outer surface, and detection of bremsstrahlung x-rays is not likely unless 
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an STC uptake is very large. While fecal sampling is a possibility, a suitable fecal sampling 

program for tritides has not been developed. 

The ultimate shortfall of fecal bioassay for tritiated particulate is that it is not 

currently available. Until the technique is available, tested, and evaluated, fecal 

bioassay for tritiated particulate cannot be implemented (Mound 2004). 

Particulate air monitoring has been chosen as the method of choice for estimation of intakes in 

lieu of adequate bioassay techniques. According to Mound Technical Basis Document for Stable 

Tritiated Particulates and Organically Bound Tritium (Mound 2004): 

The expected uncertainty range in the assigned dose from air sampling is <2 

orders of magnitude, which in fact represents a range of overestimation. This is 

much less than the expected uncertainty range, from urine of 3-4 orders of 

magnitude. 

Particulate air monitoring shortfalls for tritiated particulates are: 

(1) The self-absorption factor varies as a function of material and particle size by a factor of 

approximately 10. 

(2) The activity collected and measured on filters under-represents the actual activity 

available for deposition in the lungs. 

(3) The measured activity overestimates intake because of capture of non-respirable 

particulates on the filter. 

(4) The air sample must represent the workers’ breathing zone. Personnel air sampling is 

preferred over general area air sampling, because it is more representative of the worker 

breathing zone. 

Uncertainties with the use of air monitoring, particularly general air monitoring, would be 

substantial and methods of air monitoring and the availability of appropriate air monitoring 

techniques in areas handling STCs is uncertain. 

The potential exposure to STCs is significant in facilities that either directly handled these 

compounds, or in facilities that handled high quantities of elemental tritium and tritium oxide. 

Difficulties in area monitoring can inhibit the ability to measure STCs in the workplace. 

Furthermore, lack of adequate bioassay techniques limits the ability to identify uptakes which 

may have occurred. Potential exposures are not limited to hands-on workers, but also affect 

decontamination and decommissioning and maintenance workers. 

2.4 DOSE ASSESSMENT BASED ON AVAILABLE ICRP MODELS 

As part of its assessment of OTIB-0066, SC&A reviewed the available data in the open literature 

and derived dose coefficients based on ORAUT-OTIB-0011 (ORAUT 2004), with biokinetic 

models given in ICRP Publications 56 and 67 (ICRP 1989, ICRP 1993) considering Type M and 

Type S solubility classes for metal tritides. The dose coefficients are presented in Table 3 for soft 

tissue, lung, and colon; considering inhalation of vapor (HTO and OBT) and particles (SMT) 
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with AMAD = 1μm and 5 μm. The table also presents the dose coefficients from ICRP 

Publication 78 (ICRP 1997) for HTO and OBT. 

Table 3. Comparison of Calculated Doses for a 1-pCi Acute Intake of Tritium Compounds 

Dose Coefficients (mrem/pCi) 

Methodology (organ) SMT 

(Type S) 

SMT 

(Type M) HTO OBT 

ORAUT-OTIB-11 (Soft tissue) 6.58E-10 7.28E-09 7.11E-08 1.08E-07

AIDEc (Soft tissue) 6.30E-10a 6.93E-09a 6.76E-08b 1.52E-07b

AIDEc (Lung) 3.86E-06a 5.52E-07a 6.76E-08b 1.52E-07b

AIDEc (Colon) 3.16E-07a 2.87E-07a 6.76E-08b 1.52E-07b

ICRP 78 (Soft tissue) - - 6.66E-08b 1.52E-7b

Notes: a. Dose coefficients derived considering AMAD = 5μm 

b. Dose coefficients derived considering vapor 

c. Computer code for internal dose calculation 

2.5 SC&A COMMENTS 

2.5.1 Agreement with ORAUT-OTIB-0066 

Issue 1 (observation): SC&A has found that ORAUT-OTIB-0066 is clear and consistent with 

International Commission on Radiological Protection (ICRP) Publications 56 (ICRP 1989) and 

67 (ICRP 1993), ORAUT-OTIB-0011, and open literature (Balonov et al. 1984 and 1995; Cheng 

et al. 1997, 1999, 2002a, and 2002b; Inkret et al. 2001; Zhou and Cheng 2003; Hodgson et al. 

2004; and Zhou and Cheng 2004). 

Issue 2 (observation): The procedure provides adequate and valid technical information and 

guidance to evaluate the dose due to the intake of HTO, OBT, and SMT, applying the ICRP 

models in IMBA. 

This observation is not withstanding implementation difficulties discussed in Section 2.4.2. 

2.5.2 Disagreement with ORAUT-OTIB-0066 

Issue 3 (Finding): The recommendation given in ORAUT-OTIB-0066 to assess dose due to 

intake of OBT is not claimant favorable. The OTIB recommends the use of the methodology 

given in ORAUT-OTIB-0011 to calculate doses from intakes of OBT to all organs and tissues. 

The dose coefficient for OBT given in ICRP Publication 78 (ICRP 1997), which is 1.52 × 

10-7 mrem/pCi (see Table 3); the one derived applying the biokinetic model for OBT (ICRP 

1989; ICRP 1993; ICRP 1995; and ICRP 1997) using the AIDE computer code, which is 1.52 × 

10-7 mrem/pCi (see Table 3); and the one derived using the methodology given in ORAUTOTIB-0066 (ORAUT 2007), which is also 1.52 × 10-7 mrem/pCi (see Table 2), are 1.4 times 

higher than the one obtained applying the methodology given in ORAUT-OTIB-0011 (ORAUT 

2004), which is 1.08 × 10-7 mrem/pCi. 
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Issue 4 (Finding): The types of special tritium compounds, the quantities handled, the time 

periods of potential exposures, and the physical behavior of the tritium compounds in the 

environment must be known to effectively develop and apply OTIB-0066. 

Bounding techniques proposed in ORAUT-OTIB-0066, cannot be effectively developed and 

applied without some basic understanding of the special tritium compounds handled, the 

quantities of material, the locations and time periods of potential exposure, and the physical 

behaviors of tritium compounds in the environment (e.g., conversion to HTO, formation of rust) 

to correctly characterize tritium exposure. This is partially confirmed in ORAUT-OTIB-0066 by 

the following recommendation (ORAUT 2007). 

In the vast majority of occupational exposures to tritium it is not possible to 

identify the tritium compounds taken into the body based on the observed 

excretion. Therefore, the selection of the appropriate tritium compound in an 

intake evaluation must usually be based on process knowledge of the source terms 

in the workplace (pg. 10). 

There are several input parameters critical to the application of OTIB-0066 that must be 

determined prior to application of the model at particular DOE sites: 

 Compounds of tritium handled 

 Quantities of material handled 

 Particle size and shape of insoluble STCs 

 Ratios of tritium to metal 

 Locations where STCs were handled 

 Time periods of potential exposure 

 Engineering controls used for processing at a particular site 

 Production of compounds from adsorption of HT and HTO 

 Which workers came in contact with these materials 

This is critical information because of the inadequacies in personnel and area monitoring 

programs prior to the 1990s. In many cases, characterization efforts to identify and locate STCs 

were limited. Some thought should be given to the chemical behavior of tritium, especially as it 

related to the decontamination and decommissioning of aging tritium facilities and other 

facilities where tritium was a byproduct of operations. 

Characterization of STCs in the work environment is difficult because information may not be 

easily assessable and, in some cases, does not exist; process descriptions and documentation can 

be difficult to obtain; the CATI process does not allow for disclosure of key information from the 

energy employee unless special arrangements are made; and, in many cases, claimants are not 

aware of the STCs handled at the facility. 

Identification of who were exposed, when they were exposed, and to what compounds they were 

exposed, can be difficult. This is compounded by the potential exposure to STCs formed in 

work environments that handled large quantities of elemental tritium and HTO (e.g., formation 

of rust, particulate dust). These sources of STCs can affect a larger number of workers in 
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facilities where tritium was present. There was also an inadequacy of early monitoring 

techniques to detect some STCs. 

Issue 5 (Finding): OTIB-0066 does not ensure that resultant doses are based on adequate 

monitoring data. 

Several factors contribute to the adequacy of monitoring data used as input to the proposed 

models. The purpose of OTIB-0066 is (ORAUT 2007): 

.... to provide guidance on how to use urine bioassay data to calculate the best 

estimates of the annual organ doses for intakes of tritium bound to organic 

compounds (organically bound tritium; OBT) and tritium in a metal matrix 

(stable metal tritides; SMT) (5). 

Although urinalysis is the basis for application of the models outlined in OTIB-0066, there is no 

discussion on the practical interpretation on urinalysis results and the technical shortfalls 

associated with this technique for insoluble tritiated particulates. For insoluble tritiated 

particulates, effective methods for personnel and area monitoring were not implemented during 

periods of production and decontamination and decommissioning in many cases. As previously 

mentioned, insoluble STCs can be difficult to detect in urine because of the low dissolution rates 

of some compounds. The rates for the same compounds can vary by particle size and shape, 

making it difficult to predict how insoluble tritiated particulates will behave in the urine. 

Suitable methods for detection of tritium in fecal samples are currently not available (Mound 

2004). In-vivo counting is not feasible, because the beta particle will not escape the body. 

Furthermore, Mound (2004) states that it may not be possible to accurately monitor for surface 

and skin contamination when dealing with stable metal tritides. The method of choice for 

personnel monitoring is particulate air monitoring; however, there are multiple issues with the 

use of these data. 

The procedure does not provide information to the dose reconstructors on the characteristics of 

STC excretion in urine in practical situations enabling them under optimal circumstances to 

distinguish patterns of excretion from STCs. For example, McConville and Woods (1995) 

demonstrated, with individual excretion data following tritide uptakes, that tritium excretion 

curves for particulate tritides do not follow a simple exponential curve, as is the case with HTO. 

In the case of these individuals, tritides build up for a few days followed by a more traditional 

elimination curve. 

McConville & Woods 1995 go on to raise the following concerns about dose assessment for 

uptakes of metal tritides: 

Tritium in the form of metal tritides particles presents a peculiar problem for the 

calculation of internal dose. Standard calculations indicate that just a few 3 to 

5 micron sized particles appears to lead to a very large dose. There are very few 

data on which calculations can be based. 
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Furthermore, 

As the dissolution rate for an SMT approaches zero, the calculated intake (and 

dose rate to the lung) becomes very large, and small uncertainties in urine 

measurements can lead to significant uncertainty in the resulting (calculated) 

dose (Mound 2004). 

However, because dissolution rates vary by orders of magnitude, including some very slow rates, 

choice of a very slow dissolution rate can lead to intake (and dose) estimates which are 

overestimated by orders of magnitude when derived from urine data. This overestimate is 

compounded when intakes of HTO accompany particulate intake and increase the concentration 

in the urine. Biokinetic information is not available in the open literature or through other 

sources for all compounds of special tritium compound handled at DOE sites. In some cases, the 

dissolution factor for compounds must also be determined. 

Issue 6 (Finding): The procedure provides no guidance on how to distinguish between intakes 

of STCs, elemental tritium, and/or tritiated water which occur simultaneously or overlap. 

Circumstances exist where workers may come in contact with multiple forms of tritium during 

the course of their work. Tritiated water, tritium gas, and soluble STCs can be readily evaluated 

via urine bioassay. As such, they can mask uptakes of insoluble STCs. 

In urine bioassay, the excreted tritium from an HTO intake is indistinguishable 

from the excreted tritium from a tritiated particulate intake, largely obscuring the 

bioassay results from tritiated particulate. However, tritium from HTO and 

particulate could be distinguishable in.fecal analysis..... Presence of OBT in fecal 

samples might not be distinguishable from tritiated particulate, however, and 

would serve to obscure particulate results (Mound 2004). 

In practice, the sites have assumed all tritium uptakes were from elemental tritium or tritium 

oxide; thus, dose calculations (sometimes the only values available) incorporate the default 

parameters for tritium oxide. OTIB-0066 proposes the use of Type S solubility when the SMT is 

unknown. When soluble forms of tritium are measured in the urine, and Type S SMTs are 

assumed, this procedure can grossly overestimate the exposure, giving values which are 

implausible. 

It is important that the dose reconstructor chooses claimant-favorable forms of tritium for the 

dose estimation if there is a lack of process knowledge about the form that may have been 

involved with exposures. The dose to the lung from intakes of SMTs can be underestimated by 

orders of magnitude if it is incorrectly assumed that the dose can be calculated with the methods 

used for HTO (ORAUT 2007). Furthermore, doses obtained in a bounding technique must be 

plausible. 
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NOTICE:

2.5.3 SC&A Recommendations 

(1) The ORAUT-OTIB-0011 methodology should be applied just for tritiated water (HTO). 

(2) The ICRP biokinetic model for OBT must be applied in IMBA to assess the organ doses 

due to intake of OBT. 

(3) The ICRP biokinetic model for HTO, along with the lung retention parameters for Type 

M or Type S, must be applied in IMBA to assess the organ doses due to intake of SMT. 

(4) Characterization of the potential tritium exposure at a facility including STCs (produced 

or byproducts) is critical to the application of models in OTIB-0066 and must be 

documented more fully. Claimant favorable assumptions cannot be made in the absence 

of this information. 

(5) OTIB-0066 should consider the availability and adequacy of data used in the model and 

how the shortfalls of these data will be addressed. 
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3.0 PROCEDURE CHECKLIST 

SC&A reviewed the OTIB in accordance with its procedure, A Protocol for the Review of 

Procedures and Methods Employed by NIOSH for Dose Reconstruction (SC&A 2004). Table 4 

is taken from that procedure. Since the table has general applicability, not all of its items are 

germane to the review of the OTIB. 

Table 4: Procedure Review Outline/Checklist 

No. Description of Objective Rating 

1-5* Comments 

1.0 Determine the degree to which procedures support a process that is expeditious and timely 

for dose reconstruction 

1.1 Is the procedure written in a style that is clear and 

unambiguous? 

See 

Comment

5- Description of the 

available models 

2- Application of the 

model to DRs 

1.2 Is the procedure written in a manner that presents the 

data in a logical sequence? 

5 

1.3 Is the procedure complete in terms of required data (i.e., 

does not reference other sources that are needed for 

additional data)? 

2 In order to apply this 

proposed model, one has 

to rely on OTIB-0011. 

1.4 Is the procedure consistent with all other procedures that 

are part of the hierarchy of procedures employed by 

NIOSH for dose reconstruction? 

5 Consistent with ORAUTOTIB-0011. 

1.5 Is the procedure sufficiently prescriptive in order to 

minimize the need for subjective decisions and data 

interpretation? 

2 The procedure provides a 

model, but does not 

discuss the practical 

application of the models. 

Furthermore, it does not 

provide guidance on 

distinguishing exposures to 

STCs in the presence of 

other tritium compounds. 

2.0 Determine whether the procedure provides adequate guidance to be efficient in instances 

where a more detailed approach to dose reconstruction would not affect the outcome 

2.1 Does the procedure provide adequate guidance for 

identifying a potentially high probability of causation as 

part of an initial dose evaluation of a claim? 

2 The procedure provides 

insufficient guidance for 

identifying potential 

exposures and applying the 

OTIB. 

2.2 Conversely, for claims with suspected cumulative low 

doses, does the procedure provide clear guidance in 

defining worst-case assumptions? 

2 OTIB-0066 does not 

consider the difficulties 

associated with adequate 

personnel monitoring 

data and how this will 

impact the application.
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Table 4: Procedure Review Outline/Checklist 

No. Description of Objective Rating 

1-5* Comments 

3.0 Assess the extent to which procedures account for all potential exposures and ensure that 

resultant doses are complete and based on adequate data 

3.1 Assess quality of data collected via interviews: N/A 

3.1.1 Is scope of information sufficiently comprehensive? N/A 

3.1.2 Is the interview process sufficiently flexible to permit 

unforeseen lines of inquiry? 

N/A 

3.1.3 Does the interview process demonstrate objectivity, and 

is it free of bias? 

N/A 

3.1.4 Is the interview process sensitive to the claimant? N/A 

3.1.5 Does the interview process protect information as 

required under the Privacy Act? 

N/A 

3.2 Adequacy and use of site specific data pertaining to: 

3.2.1 Personal dosimeters (e.g., film, TLD, PICs) N/A 

3.2.2 In-vivo/in-vitro bioassays 2 The procedure does not 

consider the problems 

associated with in-vitro 

monitoring for insoluble 

STCs. 

3.2.3 Missing dosimetry data 2 The OTIB fails to consider 

the availability of raw 

tritium bioassay data. 

Tritium was often 

calculated in terms of dose 

and considered a part of 

the whole-body exposure. 

At some sites, dose data is 

the only readily available 

monitoring data. 

3.2.4 Unmonitored periods of exposure 2 The concern over STCs in 

the work environmental 

and their unique 

characteristics has only 

recently been raised. Prior 

to the late 1990s, it is 

unlikely mechanisms were 

being implemented for the 

specific measurement of 

insoluble STCs. 
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Table 4: Procedure Review Outline/Checklist 

No. Description of Objective Rating 

1-5* Comments 

4.0 Assess procedure for providing a consistent approach to dose reconstruction regardless of 

claimant’s exposures by time and employment locations

4.1 Does the procedure support a prescriptive approach to 

dose reconstruction? 

2 OTIB-0066 presents a 

model for application 

which is based on 

international standards, 

and does not consider 

DOE site-specific 

information including 

types of special tritium 

compounds, the 

quantities handled, the 

time periods of potential 

exposures, and the 

physical behavior of the 

tritium compounds in 

the environment. 

4.2 Does the procedure adhere to the hierarchical process as 

defined in 42 CFR 82.2? 

4 

5.0 Evaluate procedure with regard to fairness and giving the benefit of the doubt to the 

claimant 

5.1 Is the procedure claimant favorable in instances of 

missing data? 

3 In some cases, the 

procedure will 

overestimate dose while in 

other cases it will 

underestimate dose. There 

is still a great deal of 

information unknown 

about the biokinetic 

behavior of some STCs, so 

in some cases the proposed 

procedure cannot be 

evaluated. 

5.2 Is the procedure claimant favorable in instances of 

unknown parameters affecting dose estimates? 

3 

5.3 Is the procedure claimant favorable in instances where 

claimant was not monitored? 

3 

6.0 Evaluate procedure for its ability to adequately account for the uncertainty of dose estimates 

6.1 Does the procedure provide adequate guidance for 

selecting the types of probability distributions (i.e., 

normal, lognormal?) 

N/A 

6.2 Does the procedure give appropriate guidance in the use 

of random sampling in developing a final distribution? 

N/A 
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Table 4: Procedure Review Outline/Checklist 

No. Description of Objective Rating 

1-5* Comments 

NOTICE:

7.0 Assess procedures for striking a balance between technical precision and process efficiency 

7.1 Does the procedure require levels of detail that can 

reasonably be accounted for by the dose reconstructor? 

2 

7.2 Does the procedure avoid levels of detail that have only 

limited significance to the final dose estimate and its 

POC? 

4 

7.3 Does the procedure employ scientifically valid protocols 

for reconstructing doses? 

3 

* Rating system of 1 through 5 corresponds to the following: 1=No (Never), 2=Infrequently, 

3=Sometimes, 4=Frequently, 5=Yes (Always), N/A indicates not applicable 
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Page No. 

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 This report has been reviewed for Privacy Act information and has been cleared for distribution. 

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