Industrial Contractors 

Supplies, Inc. Surface Dust 

Guard with Diamond Wheel for 

Radiological Decontamination

Technology Evaluation Report

 EPA 600/R-11/013 | May 2011 | www.epa.gov/ord

Office of Research and Development

National Homeland Security Research Center
EPA 600/R-11/013 

 May 2011 

Technology Evaluation Report

Industrial Contractors Supplies, Inc. 

Surface Dust Guard with Diamond 

Wheel for Radiological Decontamination 

John Drake 

Task Order Project Officer 

National Homeland Security Research Center 

Office of Research and Development 

U.S. Environmental Protection Agency 

26 Martin Luther King Drive 

Cincinnati, OH 45268 
Disclaimer 

The U.S. Environmental Protection Agency (EPA), through its Office of Research and 

Development’s National Homeland Security Research Center, funded and managed this 

technology evaluation through a Blanket Purchase Agreement under General Services 

Administration contract number GS23F0011L-3 with Battelle. This report has been peer and 

administratively reviewed and has been approved for publication as an EPA document. Mention 

of trade names or commercial products does not constitute endorsement or recommendation for 

use of a specific product. 

Questions concerning this document or its application should be addressed to: 

John Drake 

National Homeland Security Research Center 

Office of Research and Development 

U.S. Environmental Protection Agency 

26 West Martin Luther King Dr. 

Cincinnati, OH 45268 

513-569-7164 

drake.john@epa.gov 

ii 
Foreword

The Environmental Protection Agency (EPA) holds responsibilities associated with homeland 

security events: EPA is the primary federal agency responsible for decontamination following a 

chemical, biological, and/or radiological (CBR) attack. The National Homeland Security 

Research Center (NHSRC) was established to conduct research and deliver scientific products 

that improve the capability of the Agency to carry out these responsibilities. 

An important goal of NHSRC’s research is to develop and deliver information on 

decontamination methods and technologies to clean up CBR contamination. When directing 

such a recovery operation, EPA and other stakeholders must identify and implement 

decontamination technologies that are appropriate for the given situation. The NHSRC has 

created the Technology Testing and Evaluation Program (TTEP) in an effort to provide reliable 

information regarding the performance of homeland security related technologies. TTEP 

provides independent, quality assured performance information that is useful to decision makers 

in purchasing or applying the tested technologies. TTEP provides potential users with unbiased, 

third-party information that can supplement vendor-provided information. Stakeholder 

involvement ensures that user needs and perspectives are incorporated into the test design so that 

useful performance information is produced for each of the tested technologies. The technology 

categories of interest include detection and monitoring, water treatment, air purification, 

decontamination, and computer modeling tools for use by those responsible for protecting 

buildings, drinking water supplies and infrastructure, and for decontaminating structures and the 

outdoor environment. Additionally, environmental persistence information is also important for 

containment and decontamination decisions. 

NHSRC is pleased to make this publication available to assist the response community to prepare 

for and recover from disasters involving CBR contamination. This research is intended to move 

EPA one step closer to achieving its homeland security goals and its overall mission of 

protecting human health and the environment while providing sustainable solutions to our 

environmental problems. 

Jonathan G. Herrmann, Director 

National Homeland Security Research Center 

iii 
Acknowledgments

Contributions of the following individuals and organizations to the development of this document are 

gratefully acknowledged. 

United States Environmental Protection Agency (EPA) 

 John Drake 

Emily Snyder 

Sang Don Lee 

Lukas Oudejans 

David Musick 

Kathy Hall 

Eletha Brady-Roberts 

Jim Mitchell 

University of Tennessee

Howard Hall 

United States Department of Energy’s Idaho National Laboratories 

Battelle Memorial Institute

iv 
Contents 

Foreword ........................................................................................................................................ iii

Acknowledgments.......................................................................................................................... iv

Abbreviations/Acronyms .............................................................................................................. vii

Executive Summary ..................................................................................................................... viii

1.0 Introduction ...............................................................................................................................1

2.0 Technology Description ............................................................................................................3

3.0 Experimental Details .................................................................................................................4

3.1 Experiment Preparation ..................................................................................................4

3.1.1 Concrete Coupons ..............................................................................................4

3.1.2 Coupon Contamination .......................................................................................5

3.1.3 Measurement of Activity on Coupon Surface ....................................................5

3.1.4 Surface Construction Using Test Stand ..............................................................6

3.2 Evaluation Procedures ....................................................................................................6

4.0 Quality Assurance/Quality Control...........................................................................................8

4.1 Intrinsic Germanium Detector ........................................................................................8

4.2 Audits .............................................................................................................................9

4.2.1 Performance Evaluation Audit ...........................................................................9

4.2.2 Technical Systems Audit ....................................................................................9

4.2.3 Data Quality Audit ...........................................................................................10

4.3 QA/QC Reporting.........................................................................................................10

5.0 Evaluation Results ..................................................................................................................11

5.1 Decontamination Efficacy ............................................................................................11

5.2 Deployment and Operational Factors ...........................................................................12

6.0 Performance Summary ............................................................................................................15

6.1 Decontamination Efficacy ............................................................................................15

6.2 Deployment and Operational Factors ...........................................................................15

7.0 References ...............................................................................................................................16

v 
Figures 

Figure 2-1. Angle grinder equipped with SDG and DMD (left). DMD (right). ...........................3

Figure 3-1. Demonstration of contaminant application technique. ..............................................5

Figure 3-2. Containment tent: outer view (left) and inner view with test stand containing 

contaminated coupons (right). ...................................................................................6

Figure 3-3. SDG-DMD being applied to concrete coupon. ..........................................................7

Figure 5-1. Concrete coupon demonstrating surface damage. ...................................................12

Tables

Table 3-1. Characteristics of Portland Cement Clinker Used to Make Concrete Coupons .........4

Table 4-1. Calibration Results – Difference from Th-228 Calibration Energies .........................8

Table 4-2. NIST-Traceable Eu-152 Activity Standard Check .....................................................9

Table 5-1. Decontamination Efficacy Results ............................................................................12

Table 5-2. Operational Factors Gathered from the Evaluation ..................................................14

vi 
Abbreviations/Acronyms 

ANSI

ASTM

American National Standards Institute

American Society for Testing and Materials

BQ

Cs

cfm

cm

cm2

Becquerel

cesium

cubic feet per minute

centimeters

square centimeters

DARPA Defense Advanced Research Projects Agency

DF decontamination factor

DHS U.S. Department of Homeland Security

DMD

DOD

diamond cutting wheel

Department of Defense

EPA

Eu

Ft

HEPA

IEEE

INL

U.S. Environmental Protection Agency

europium

feet

High Efficiency Particulate Air 

Institute of Electrical and Electronics Engineers

Idaho National Laboratory

keV

kg

mg

mL

L

m

m2

μCi

kilo electron volts

kilogram

milligram

milliliter

liter

meter

square meters

microCurie

NHSRC

NIST

National Homeland Security Research Center

National Institute of Standards and Technology

ORD Office of Research and Development

%R percent removal

PE performance evaluation

QA quality assurance

QC quality control

QMP

RDD

quality management plan

radiological dispersion device

RML

RSD

SDG

SDG-DMD

Radiological Measurement Laboratory

relative standard deviation

Industrial Contractors Supplies, Inc. Surface Dust Guard

Industrial Contractors Supplies, Inc. Surface Dust Guard with a diamond cutting 

wheel

TSA technical systems audit

TTEP

Th

Technology Testing and Evaluation Program

thorium

V volt

 

vii 
Executive Summary 

The U.S. Environmental Protection Agency’s (EPA) National Homeland Security Research 

Center (NHSRC) is helping to protect human health and the environment from adverse impacts 

resulting from acts of terror by carrying out performance tests on homeland security 

technologies. Through its Technology Testing and Evaluation Program (TTEP), NHSRC 

evaluated the performance of the Industrial Contractors Supplies, Inc. Surface Dust Guard (SDG) 

with a diamond cutting wheel (DMD) and its ability to remove radioactive cesium (Cs)-137 from 

the surface of unpainted concrete. 

Experimental Procedures. The Industrial Contractors Supplies, Inc. SDG is a vacuum shroud 

that can be attached to almost any commercially available handheld grinder or polisher (e.g. 

Bosch, DeWalt, and Hitachi, etc). During this evaluation the SDG was used with a Makita 

9564CV angle grinder equipped with a DMD. (Hereafter this combination will be referred to as 

the SDG-DMD). This technology is designed to decontaminate by removing the surface layer 

and collecting the resulting secondary waste using a vacuum connected to the SDG. Eight 15 

centimeter (cm) × 15 cm unpainted concrete coupons were contaminated with approximately 1 

microCurie (μCi) of Cs-137 per coupon and allowed to age for seven days. The amount of 

contamination deposited on each coupon was measured using gamma spectroscopy. The eight 

contaminated coupons were placed in a test stand (along with one uncontaminated blank coupon) 

that was designed to hold nine concrete coupons in a vertical orientation to simulate the wall of a 

building. Each coupon was sanded with the SDG-DMD and the decontamination efficacy was 

determined by calculating both a decontamination factor (DF) and percent removal (%R). 

Important deployment and operational factors were also documented and reported. 

Results. The decontamination efficacy attained by the SDG-DMD was evaluated for each 

concrete coupon used during the evaluation. When the decontamination efficacy metrics (%R 

and DF) of the eight contaminated coupons were averaged together, the average %R for the 

SDG-DMD was 89 ± 8% and the average DF was 13.7 ± 8.5. Hypothesis testing was performed 

to determine if there were significant differences between the %R values determined for the 

coupons in each row (top, middle, and bottom) of the test stand. No differences were found. 

The SDG- DMD could decontaminate a vertical surface at a rate of approximately 2.7 square 

meters (m2

) per hour. The SDG- DMD caused a significant amount of surface destruction. The 

texture of the coupon surface is not likely to be important to the efficacy of the SDG-DMD and 

similar DMD wheel radiological decontamination technologies. The wheel is aggressive enough 

that it cuts through irregularities in concrete surfaces that may limit the effectiveness of less 

aggressive techniques. 

A very limited evaluation of cross-contamination was performed. During an actual 

decontamination of a vertical surface, the higher elevation surfaces would likely be 

decontaminated first, possibly exposing the lower surface to secondary contamination. To 

viii 
simulate an actual scenario, one uncontaminated coupon was placed in the bottom row of the test 

stand and decontaminated using the SDG-DMD in the same way as the other coupons. Following 

decontamination using the SDG-DMD, the uncontaminated coupon did not contain measurable 

activity, suggesting that cross contamination was minimal. 

Overall, the SDG was not entirely effective at containing the secondary waste. There was a 

significant amount of dust visible during the evaluation. In addition, the radiological control 

technicians found a small but measurable level of airborne radiological activity from particulate 

during the evaluation. The dust collected by the vacuum was not analyzed for gamma radiation. 

 

.

ix 
1.0 Introduction 

The U.S. Environmental Protection Agency’s (EPA) National Homeland Security 

Research Center (NHSRC) is helping to protect human health and the environment from 

adverse effects resulting from acts of terror. NHSRC is emphasizing decontamination and 

consequence management, water infrastructure protection, and threat and consequence 

assessment. In doing so, NHRSC is working to develop tools and information that will 

improve the ability of operational personnel to detect the intentional introduction of 

chemical, biological, or radiological contaminants on or into buildings or water systems, 

to contain or mitigate these contaminants, to decontaminate affected buildings and/or 

water systems, and to dispose of contaminated materials resulting from clean-ups. 

NHSRC, through its Technology Testing and Evaluation Program (TTEP), works in 

partnership with recognized testing organizations; with stakeholder groups consisting of 

buyers, vendor organizations, and permitters; and with the participation of individual 

technology developers in carrying out performance tests on homeland security 

technologies. The program evaluates the performance of homeland security technologies 

by developing evaluation plans that are responsive to the needs of stakeholders, 

conducting tests, collecting and analyzing data, and preparing peer-reviewed reports. All 

evaluations are conducted in accordance with rigorous quality assurance (QA) protocols 

to ensure that data of known and high quality are generated and that the results are 

defensible. TTEP provides high-quality information that is useful to decision makers in 

purchasing or applying the evaluated technologies, and in planning clean-up operations. 

TTEP provides potential users with unbiased, third-party information that can supplement 

vendor-provided information. Stakeholder involvement ensures that user needs and 

perspectives are incorporated into the evaluation design so that useful performance 

information is produced for each of the evaluated technologies. 

Under TTEP, NHSRC evaluated the performance of the Industrial Contractors Supplies, 

Inc. (Huntingdon, PA) Surface Dust Guard (SDG) with a diamond cutting wheel (DMD) 

(hereafter referred to as the SDG-DMD) in removing radioactive isotope Cs-137 from 

concrete. A peer-reviewed test/QA plan was developed according to the requirements of 

the quality management plan (QMP) for TTEP. The evaluation generated the following 

performance information for the SDG-DMD: 

# Decontamination efficacy, defined as the extent of radionuclide removal following 

the use of the SDG-DMD, and the possibility of cross-contamination. 

# Deployment and operational factors, including the approximate rate of surface area 

decontamination, applicability to irregular surfaces, skilled labor requirement, utility 

1 
requirements, portability, secondary waste management, and technology cost. 

This evaluation took place from August 11, 2009 until October 13, 2009. All of the 

experimental work took place in a radiological contamination area at the U.S. Department 

of Energy’s Idaho National Laboratory (INL). This report describes the quantitative 

results and qualitative observations gathered during the evaluation. The contractor, 

Battelle, and EPA were responsible for QA oversight. The Battelle QA Manager 

conducted both a technical systems audit (TSA) and a data quality audit of the evaluation 

data. 

2 
2.0 Technology Description 

The following description of the Industrial Contractors Supplies, Inc. SDG is based on 

information provided by the vendor and was not verified during this evaluation. 

The Industrial Contractors Supplies, Inc. SDG is a vacuum shroud that can be attached to 

almost any commercially available handheld grinder or polisher with a 5 inch wheel (e.g. 

Bosch, DeWalt, and Hitachi, etc). During this evaluation the SDG was used with a 

Makita 9564CV angle grinder equipped with a DMD (CGD30P45H, Industrial 

Contractors Supplies, Inc.). (Hence, the SDG-DMD.)The DMD was 10 cm in diameter 

and had 18 segments of 40/60 medium grit diamond crystal segments. This technology 

decontaminates bound Cs-137 from surfaces by removing the surface layer and collecting 

the resulting secondary waste using a high efficiency particulate air (HEPA) vacuum 

connected to the SDG. The vacuum was powered by 110 volt (V) electricity generating a 

flow of 136 cubic feet per minute (cfm). The angle grinder component was also powered 

by 110V electricity; according to vendor specifications, it operates at speeds up to 10,500 

revolutions per minute. Figure 2-1 shows the components of the SDG-DMD. 

Figure 2-1. Angle grinder equipped with SDG and DMD (left). DMD (right). 

3 
3.0 Experimental Details 

3.1 Experiment Preparation 

3.1.1 Concrete Coupons 

The concrete coupons were prepared from a single batch of concrete made from Type II 

Portland cement. The ready-mix company (Burns Brothers Redi-Mix, Idaho Falls, ID) 

that supplied the concrete for this evaluation provided the data which describe the cement 

clinker used in the concrete mix. For Type II Portland cement, the American Society for 

Testing and Materials (ASTM) Standard C 150-71

 specifies that tricalcium aluminate 

should account for less than 8% of the overall cement clinker (by weight). The cement 

clinker used for the concrete coupons was 4.5% tricalcium aluminate (Table 3-1). For 

Type I Portland cement the tricalcium aluminate should be less than 15%. Because Type 

I and II Portland cements differ only in tricalcium aluminate content, the cement used 

during this evaluation meets the specifications for both Type I and II Portland cements. 

Table 3-1. Characteristics of Portland Cement Clinker 

 Used to Make Concrete Coupons 

Cement Constituent Percent of Mixture 

Tricalcium Silicate 57.6 

Dicalcium Silicate 21.1 

Tricalcium Aluminate 4.5 

Tetracalcium Aluminoferrite 8.7 

Minor Constituents 8.1 

 

The wet concrete was poured into 0.9 meter (m) square plywood forms with the exposed 

surface “floated” to allow the smaller aggregate and cement paste to float to the top, and 

the concrete was then cured for 21 days. Following curing, the squares were cut to the 

desired size with a laser-guided rock saw. For this evaluation, the “floated” surface of the 

concrete coupons was used. The coupons were approximately 4 centimeters (cm) thick, 

15 cm × 15 cm square, and had a surface finish that was consistent across all the coupons. 

The concrete was representative of exterior concrete commonly found in urban 

environments in the United States as shown by INL under a previous project sponsored 

by the U.S. Department of Defense (DOD), Defense Advanced Research Projects Agency 

(DARPA) and U.S. Department of Homeland Security (DHS).2

4 
3.1.2 Coupon Contamination 

Eight coupons were contaminated by spiking individually with 2.5 milliliters (mL) of 

aqueous solution that contained 0.26 milligrams (mg)/liter (L) Cs-137 as a solution of 

cesium chloride, corresponding to an activity level of approximately 1 microCurie (μCi) 

over the 225 cm2 surface. Application of the Cs-137 in an aqueous solution was justified 

because even if Cs-137 were dispersed in a particle form following a radiological 

dispersion device (RDD) or “dirty bomb” event, morning dew or rainfall would likely 

occur before the surfaces could be decontaminated. In addition, from an experimental 

standpoint, it is much easier to apply liquids, rather than dry particles, homogeneously 

across the surface of the concrete coupons. The liquid spike was delivered to each coupon 

using an aerosolization technique developed by INL (under a DARPA/DHS project2) and 

described in detail in the test/QA plan. The coupons were then allowed to age for seven 

days. 

The aerosol delivery device was constructed of two syringes. The plunger and needle 

were removed from the first syringe and discarded. Then, a compressed air line was 

attached to the rear of the syringe. The second syringe contained the contaminant solution 

and was equipped with a 27 gauge needle, which penetrated through the plastic housing 

near the tip of the first syringe. Compressed air flowing at a rate of approximately 1 - 2 L 

per minute created a turbulent flow through the first syringe. When the contaminant 

solution in the second syringe was introduced, the solution became nebulized by the 

turbulent air flow. A fine aerosol was ejected from the tip of the first syringe creating a 

controlled and uniform spray of fine liquid droplets onto the coupon surface. The 

contaminant spray was applied all the way to the edges of the coupon which were taped 

(after having previously been sealed with polyester resin) to ensure that the contaminant 

was applied only to the surfaces of the coupons. The photographs in Figure 3-1 show this 

procedure being performed using a nonradioactive, nonhazardous aqueous dye to 

demonstrate that the 2.5 mL of contaminant solution is effectively distributed across the 

surface of the coupon. 

Figure 3-1. Demonstration of contaminant application technique.

3.1.3 Measurement of Activity on Coupon Surface

Gamma radiation from the surface of each concrete coupon was measured to quantify 

contamination levels both before and after evaluation of the ETR180. These 

5 
measurements were made using an intrinsic, high purity germanium detector (Canberra 

LEGe Model GL 2825R/S, Meriden, CT). After being placed into the detector, each 

coupon was measured until the average activity level of Cs-137 from the surface 

stabilized to a relative standard deviation of less than 2%. Gamma-ray spectra acquired 

from Cs-137 contaminated coupons were analyzed using INL Radiological Measurement 

Laboratory (RML) data acquisition and spectral analysis programs (PCGAP, Idaho 

National Engineering and Environmental Laboratory, Idaho Falls, ID; INEEL/EXT-2000-

00908; http://www.inl.gov/technicalpublications/Documents/3318133.pdf). Radionuclide 

activities on coupons were calculated based on efficiency, emission probability, and halflife values. Decay corrections were made based on the date and the duration of the 

counting period. Full RML gamma counting QA/quality control (QC), as described in the 

test/QA plan, was employed, and certified results were provided. 

3.1.4 Surface Construction Using Test Stand 

To evaluate the decontamination technologies on vertical surfaces (simulating walls), a 

stainless steel test stand was fabricated that held three rows of three concrete coupons. 

The test stand, approximately 9 feet (ft) × 9 ft, was erected within a containment tent. The 

concrete coupons were placed into holders so their surfaces extended just beyond the 

surface of the stainless steel face of the test stand. Eight of the nine coupons placed in the 

test stand were contaminated with Cs-137, which has a half-life of 30 years. One 

uncontaminated coupon was placed in the bottom row of the test stand and 

decontaminated using the SDG-DMD in the same way as the other coupons. This coupon 

was placed there to observe possible secondary contamination caused by the 

decontamination higher on the wall. Figure 3-2 shows the containment tent and the test 

stand loaded with concrete coupons. 

Figure 3-2. Containment tent: outer view 

(left) and inner view with test stand containing contaminated coupons (right). 

3.2 Evaluation Procedures 

The containment tent consisted of two rooms. One room contained the test stand to hold 

the contaminated coupons; the other room (the shorter part of the tent as shown in Figure 

3-2) held the vacuum. An opening in the tent wall between the two rooms was just large 

enough to allow the vacuum hose connected to the SDG-DMD to pass through. The tent 

6 
opening was taped closed around the hose prior to the start of the evaluation. Figure 3-3 

shows the vacuum hose connecting to the SDG as the operator applies the SDG-DMD to 

a concrete coupon.

The nine concrete coupons in the test stand were sanded using the SDG-DMD starting 

with the top row and working from left to right, then proceeding to the middle and 

bottom rows. The coupons were sanded in this manner to simulate an approach that 

would likely be taken in an actual decontamination event, where higher wall surfaces 

would be decontaminated first because of the possibility of secondary contamination 

lower on the wall. The SDG-DMD was connected to the vacuum and operated at full 

power for 20-30 seconds on each coupon, enough time to ensure that the entire surface of 

each had been covered. This procedure would correspond to a rate of coverage ranging 

from 0.2 m2 to 0.3 m2 per minute. The temperature and relative humidity were recorded 

before and after the approximately one hour test. These conditions did not vary 

significantly in the room where the evaluation was performed. Over the duration of 

testing, the temperature was 17.7 °C and the relative humidity was 26%. 

Figure 3-3. SDG-DMD being applied to concrete coupon.

7 
4.0 Quality Assurance/Quality Control

QA/ QC procedures were performed in accordance with the program QMP and the 

test/QA plan for this evaluation. 

4.1 Intrinsic Germanium Detector

The germanium detector was calibrated once each week. The calibration was performed 

in accordance with standardized procedures from the American National Standards 

Institute (ANSI) and the Institute of Electrical and Electronics Engineers (IEEE).3

 In 

brief, detector energy was calibrated using thorium (Th)-228 daughter gamma rays at 

238.6, 583.2, 860.6, 1620.7, and 2614.5 kilo electron volts (keV). This calibration was 

performed three times during the overall project and documented by the RML. Table 4-1 

gives the difference between the known energy levels and those measured following 

calibration. The energies were compared to the previous 30 calibrations to confirm that 

the results were within three standard deviations of the previous calibration results. The 

calibrations are shown for the detector used during this evaluation. All the calibrations 

fell within this requirement. 

Table 4-1. Calibration Results – Difference from Th-228 Calibration Energies 

Date 

Calibration Energy Levels (keV) 

Energy 1 

238.632 

Energy 2 

583.191 

Energy 3 

860.564 

Energy 4 

1620.735 

Energy 5 

2614.533 

8-25-2009 -0.005 0.014 -0.031 -0.199 0.031 

9-21-2009 -0.003 0.009 -0.040 -0.125 0.015 

10-13-2009 -0.003 0.008 -0.011 -0.180 0.020 

Gamma ray counting was continued on each coupon until the activity level of Cs-137 on 

the surface had a relative standard deviation (RSD) of less than 2%. This RSD occurred 

within an initial 1 hour of counting for all the coupons measured during this evaluation. 

The final activity assigned to each coupon was a compilation of information obtained 

from all components of the electronic assemblage that comprise the "gamma counter," 

including the raw data and the spectral analysis described in Section 3.1.3. Final spectra 

and all data that comprise the spectra were sent to a data analyst who independently 

confirmed the "activity" number arrived at by the spectroscopist. When both the 

spectroscopist and an expert data analyst independently arrived at the same value the data 

were considered certified. This process defines the full gamma counting QA process for 

certified results. 

8 
The background activity of the concrete coupons was determined by analyzing nine 

arbitrarily selected coupons from the stock of concrete coupons used for this evaluation. 

The ambient activity level of these coupons was measured for at least two hours. No 

activity was detected above the minimum detectable level of 2×10-4 μCi on these 

coupons. Because the background activity was not detectable (and the detectable level 

was 600 times lower than the post-decontamination activity levels), no background 

subtraction was required. 

Throughout the evaluation, a second measurement was taken on 10 coupons in order to 

provide duplicate measurements to evaluate the repeatability of the instrument. Half of 

the duplicate measurements were performed after contamination prior to application of 

the decontamination technology and half were performed after decontamination. Five of 

the duplicate pairs showed no difference in activity levels between the two 

measurements; the other five duplicate pairs had a difference of 2% between the two 

measurements, within the acceptable difference of 5%. 

4.2 Audits

4.2.1 Performance Evaluation Audit

RML performed regular checks of the accuracy of the Th-228 daughter calibration 

standards (during the time when the detector was in use) by measuring the activity of a 

National Institute of Standards and Technology (NIST)-traceable europium (Eu)-152 

standard (in units of Becquerel, BQ) and comparing it to the accepted NIST value. 

Results within 7% of the NIST value are considered to be within acceptable limits. The 

Eu-152 activity comparison is a routine QC activity performed by INL, but for the 

purposes of this evaluation serves as the performance evaluation (PE) audit, an audit that 

confirms the accuracy of the calibration standards used for the instrumentation critical to 

the results of an evaluation. Table 4-2 gives the results of each of the audits applicable to 

the duration of the evaluation. All results are below the acceptable difference of 7%. 

Table 4-2. NIST-Traceable Eu-152 Activity Standard Check 

Date 

NIST Activity 

(BQ) 

INL RML 

Result (BQ)

Relative 

Percent 

Difference 

8-18-2009 124,600 122,400 2% 

9-10-2009 124,600 122,600 2% 

10-12-2009 124,600 122,300 2% 

4.2.2 Technical Systems Audit 

A TSA was conducted during testing at INL to ensure that the evaluation was performed 

in accordance with the test/QA plan and the TTEP QMP. As part of the audit, the actual 

9 
evaluation procedures were compared with those specified in the test/QA plan, and the 

data acquisition and handling procedures were reviewed. No significant adverse findings 

were noted in this audit. The records concerning the TSA are stored indefinitely with the 

Battelle QA Manager.

4.2.3 Data Quality Audit

The Battelle QA Manager verified all of the raw data acquired during the evaluation and 

transcribed into spreadsheets for use in the final report. The data were traced from the 

initial raw data collection, through reduction and statistical analysis, to final reporting, to 

ensure the integrity of the reported results. 

4.3 QA/QC Reporting 

Each assessment and audit was documented in accordance with the test/QA plan and the 

QMP. The Battelle QA Manager prepared the draft assessment report and sent it to the 

Test Coordinator and Battelle TTEP Program Manager for review and approval. The 

Battelle QA Manager then sent the final assessment report to the EPA QA Manager and 

Battelle staff. 

 

10 
5.0 Evaluation Results 

5.1 Decontamination Efficacy 

The decontamination efficacy of the SDG-DMD was measured for each contaminated 

coupon in terms of percent removal (%R) and decontamination factor (DF). Both of these 

measurements provide a means of representing the extent of decontamination 

accomplished by a technology. The %R gives the extent as a percent relative to the 

activity and the DF is the ratio of the initial activity to the final activity or the factor by 

which the activity was decreased. These terms are defined by the following equations: 

 %R = (1-Af/Ao) × 100% and DF = Ao/Af 

where Ao is the radiological activity from the surface of the coupon before application of 

the SDG-DMD and Af is radiological activity from the surface of the coupon after 

treatment. While the DFs are reported, the narrative describing the results focuses on the 

%R. 

Table 5-1 gives the %R and DF for the SDG-DMD. All coupons were oriented vertically. 

The target activity for each of the contaminated coupons (pre-decontamination) was 

within the acceptable range of 1 μCi ± 0.5 μCi. The overall average (plus or minus one 

standard deviation) of the contaminated coupons was 1.13 μCi ± 0.07 μCi, a variability of 

6%. The post-decontamination coupon activities were less than the pre-decontamination 

activities, showing an overall reduction in activity. The %R averaged 89% ± 8% and the 

DF averaged 13.7 ± 8.5. Overall, the %R ranged from 72% to 97% and the DF ranged 

from 3.5 to 30.5. 

Paired t-tests were performed at a 95% confidence interval to determine whether location 

(top, middle, or bottom) on the test stand affected the decontamination efficacy. While 

the average %R for the top row (95% ± 2%) of coupons was slightly higher than the 

middle (84%± 11%) and bottom (88%± 6%) rows, no significant difference between any 

of the rows was found. The bottom middle coupon was not contaminated to test the 

possibility of cross-contamination. Activity of the uncontaminated coupon was measured 

after all nine coupons had been decontaminated using the SDG-DMD. No activity was 

detected on the uncontaminated coupon, suggesting that cross-contamination due to the 

application of the SDG-DMD was minimal. 

11 
Table 5-1. Decontamination Efficacy Results 

Coupon 

Location in 

Test Stand

Pre-Decon Activity 

μCi / Coupon

Post-Decon Activity 

μCi / Coupon %R DF

Top left 1.19 0.07 94 17.4

Top middle 1.14 0.07 94 15.6

Top right 1.16 0.04 97 30.5

Center left 1.12 0.07 94 16.6

Center middle 1.18 0.15 87 7.7

Center right 1.10 0.31 72 3.5

Bottom left 1.18 0.10 92 11.9

Bottom right 0.99 0.16 84 6.2

Average 1.13 0.12 89 13.7

Std. Dev 0.07 0.09 8 8.5

5.2 Deployment and Operational Factors

A number of operational factors were documented by the SDG-DMD operator. One of 

the factors was damage to the surface of the concrete coupons. Figure 5-1 shows a noncontaminated coupon that has had the bottom third sanded with the SDG-DMD and the 

top two-thirds left unsanded. The slight pink color is due to a dye that was applied to the 

surface of this noncontaminated coupon for illustrative purposes. The bottom of the 

coupon has had the surface characteristics (pink color, smooth concrete finish, etc.) 

stripped away. One large piece of aggregate on the left side of the coupon fell out during 

sanding; several dark colored pieces of aggregate are visible in the bottom third but not in 

the top two-thirds of the coupon. The SDG-DMD can damage any concrete surface on 

which it is used. 

Figure 5-1. Concrete coupon demonstrating surface damage. 

12 
Other important factors to consider are the personal protection of the technology 

operators and the secondary waste management of a decontamination technology. During 

this evaluation, the radiological control technicians required the operators to wear full 

anti-contamination personal protective equipment that included a full face respirator with 

supplied air. This level of personal protection was required because of the likelihood of 

airborne radiological contamination due to the act of sanding. However, each situation 

will need to be considered independently by local RCTs to determine the proper level of 

personal protection. Overall, the SDG was not entirely effective at containing the 

secondary waste. During the evaluation a significant amount of dust was visible and the 

radiological control technicians found a small, but measurable, level of airborne 

radiological activity. Because the vacuum was in a separate room of the tent, the vacuum 

is unlikely to have contributed to the airborne contamination. In an actual 

decontamination situation, the possibility of the release of airborne radiological activity 

would be a safety concern.

Table 5-2 summarizes qualitative and quantitative practical information gained by the 

operator during the evaluation of the SDG-DMD. All of the operational information was 

gathered during use of SDG-DMD on the concrete coupons inserted into the test stand. 

Some of the information given in Table 5-2 could differ if the SDG-DMD were applied 

to a larger surface or a surface that was smoother or more rough and jagged than the 

concrete coupons used during this evaluation. 

13 
Table 5-2. Operational Factors Gathered from the Evaluation 

Parameter Description/Information

Decontamination 

rate 

Technology Preparation: 5 minutes to attach diamond wheel and SDG to 

angle grinder.

Application: 20-30 seconds per concrete coupon used during this evaluation 

corresponds to an application rate of approximately 2.7 m2

/hour; less or more 

time per coupon may result in different levels of radiological 

decontamination.

Applicability to 

irregular surfaces

Irregular surfaces would likely not be a problem for the SDG-DMD as the 

diamond wheel is an aggressive decontamination technique, removing the 

surface of the concrete, making the SDG-DMD not dependent on the surface 

characteristics of the concrete. 

Skilled labor 

requirement

The SDG-DMD is an extremely basic technology requiring minimal training. 

Adequate training would likely include a few minutes of orientation so the 

operator is familiar with the power switches on the vacuum and the SDGDMD. 

The SDG-DMD weighs approximately 2 kilogram (kg). The operator during 

this evaluation experienced a significant level of exertion as he completed the 

evaluation. The weight of the SDG-DMD, in combination with the additional 

weight and awkwardness of the attached vacuum line, increased the level of 

effort required to use the SDG-DMD. Depending on what row of the test 

stand was being used, the operator was required to bend over, stand on the 

floor or stand up on a ladder. Each of these situations required a significant 

amount of exertion. These factors will exclude some people from being able 

to operate the SDG-DMD. However, most people who are used to 

performing physical labor should not have any problem operating the SDGDMD.

Utilities 

requirement

110 V power for both the SDG-DMD and a 136 cfm vacuum. 

Portability The limiting factors of portability for the SDG-DMD will include the 

availability of power and the ability to connect to the vacuum by staying close 

enough to the vacuum or by having a vacuum hose of adequate length.

Decontamination

media

The same DMD was used for all nine coupons that were decontaminated.

Secondary waste 

management

Some dust was expelled from the DMD and vacuum shroud during testing. 

The radiological control technicians who observed the testing collected 

airborne particulate and detected small, but measurable amounts of activity in 

the air during evaluation of the SDG-DMD. The activity of the dust collected 

by the vacuum or vacuum filter was not measured quantitatively. However, 

given the effectiveness of the SDG-DMD, presumably the waste had 

significant activity levels.

Surface damage See description and picture in text.

Cost $1,000 for the entire system, including the angle grinder, SDG, and vacuum. 

The SDG alone costs $235.

14 
6.0 Performance Summary 

This section presents the findings from the evaluation of the SDG-DMD for each 

performance parameter evaluated. 

6.1 Decontamination Efficacy 

The decontamination efficacy (in terms of %R) attained by the SDG-DMD was evaluated 

for each concrete coupon used during the evaluation. When the decontamination efficacy 

metrics (%R and DF) of the eight contaminated coupons were averaged together, the 

average %R for the SDG-DMD was 89 ± 8% and the average DF was 13.7 ± 8.5. 

Hypothesis testing was performed to determine if there were significant differences 

between the %R values determined for the coupons in each row (top, middle, and bottom) 

of the test stand. No differences were found. 

6.2 Deployment and Operational Factors 

The SDG- DMD could decontaminate a vertical surface at a rate of approximately 2.7 m2

per hour. The SDG- DMD caused a significant amount of surface destruction. The texture 

of the coupon surface is not likely to be important to the efficacy of the SDG-DMD and 

similar DMD wheel radiological decontamination technologies. The wheel is aggressive 

enough that it cuts through irregularities in concrete surfaces that may limit the 

effectiveness of less aggressive techniques. 

A very limited evaluation of cross-contamination was performed. During an actual 

decontamination of a vertical surface, the higher elevation surfaces would likely be 

decontaminated first, possibly exposing the lower surface to secondary contamination. To 

simulate an actual scenario, one uncontaminated coupon was placed in the bottom row of 

the test stand and decontaminated using the SDG-DMD in the same way as the other 

coupons. Following decontamination using the SDG-DMD, the uncontaminated coupon 

did not contain measurable activity, suggesting that cross contamination was minimal. 

Overall, the SDG was not entirely effective at containing the secondary waste. There was 

a significant amount of dust visible during the evaluation. In addition, the radiological 

control technicians found a small but measurable level of airborne radiological activity 

15 
from particulate during the evaluation. The dust collected by the vacuum was not 

analyzed for gamma radiation. 

7.0 References 

1. ASTM Standard C 150-07, 2007, “Standard Specification for Portland Cement,” 

ASTM International, West Conshohocken, PA, www.astm.org. 

2. Radionuclide Detection and Decontamination Program. Broad Agency 

Announcement 03-013, U.S. Department of Defense (DOD) Defense Advanced 

Research Projects Agency (DARPA) and the U.S. Department of Homeland Security, 

classified program. 

3. Calibration and Use of Germanium Spectrometers for the Measurement of Gamma 

Emission Rates of Radionuclides, American National Standards Institute. ANSI 

N42.14-1999. IEEE New York, N.Y. (Rev. 2004). 

16 
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