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technical BR
Technology Performance Summary for
Chemical Detection Instruments
Sixteen Instruments Tested to Determine Their Capability to
Screen Samples Submitted to All Hazards Receipt Facilities
All Hazards Receipt Facilities (AHRFs) were developed to
prescreen for chemical, radiochemical, and explosive hazards
in samples collected during suspected terrorist attacks. The
technologies (i.e., instruments) used in AHRFs are intended
to screen samples prior to a full analysis, helping protect
responders, laboratory workers, and others from potential injury.
Evaluations of these technologies are summarized in two
technology evaluation reports:
1) Testing of Screening Technologies for Detection of Chemical
Warfare Agents in All Hazards Receipt Facilities (CWAs)
2) Testing of Screening Technologies for Detection of Toxic
Industrial Chemicals in All Hazards Receipt Facilities (TICs)
The chemicals included in the reports were chosen because
they might be used during, or develop as a by-product
from, a terrorist attack.
EPA's National Homeland Security
Research Center (NHSRC) develops
products based on scientific research
and technology evaluations. Our
products and expertise are widely used in
preventing, preparing for, and recovering
from public health and environmental
emergencies that arise from terrorist
attacks. Our research and products
address biological, radiological, or
chemical warfare agents that could affect
indoor areas, outdoor areas, or water
infrastructures. NHSRC rigorously tests
technologies against a wide range of
performance characteristics,
requirements, and specifications.
Technology testing and evaluation is
an effort to provide reliable information
regarding the performance of
commercially available technologies
that may have application for homeland
security.
The screening technologies are intended:
To be rapid and qualitative
To be simple to use and of relatively low cost
To indicate if samples contain hazardous chemicals of concern.
Not all of the technologies evaluated were deemed suitable for the AHRF, although they might be
useful for on scene responders.
Technology Descriptions
The screening technologies tested were chosen based on a
review of commercially available detection devices. From the
variety of detection instruments reviewed, 16 screening
technologies were selected for testing based on their
suitability for use in AHRFs.
The 16 technologies ranged from simple test papers, kits,
and color-indicating tubes to hand-held electronic detectors
based on ion mobility spectrometry (IMS), photoionization
detection (PID), and flame spectrophotometry (FSP). Each
technology was tested with three replicate samples for each
matrix (vapor, liquid, or on a surface) containing either a
CWA or TIC. CWAs and TICs were tested at concentrations
This document does not constitute nor should be construed as an EPA endorsement of any particular product,
service, or technology.
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known to be hazardous to humans within a few minutes of exposure (e.g., AEGL = Acute Exposure
Guide Level (www.epa.gov/opptintr/aegl) and RDT&E = Research, Development, Test, and
Evaluation Standards (Chemical Surety, Chapter 6: Army Regulation 50-6, 26 June 2001)).
The following performance parameters were evaluated for each technology:
Identifying the number of false positives/false negatives and the repeatability of test results
Time in which the instrument detected the presence of a chemical (i.e., response time)
Operational information including ease of use and response indication (e.g., color change
indicating chemical detection)
Cost including initial, sample, and continuing operating costs.
Technologies were tested to determine their detection capability for the following hazardous
chemicals in different matrices:
Hydrogen cyanide
Cyanogen chloride
Phosgene
Chlorine
Hydrogen sulfide
Arsine
Sarin
Sulfur mustard
Cyanide
Hydrogen peroxide
Fluoride
Sarin
Sulfur mustard
Nerve agent (VX)
Nerve agent (VX)
Testing Methodologies
Each technology was tested with one chemical target agent at a time.
Vapor Testing - Each screening technology was first sampled (or was exposed to) the clean air
flow, and any response or indication from the screening technology was noted. After this background
measurement, the 4-way valve was switched to the challenge plenum to deliver the target gas. The
sequence of exposure to clean air, followed by exposure to the target gas, was carried out three times
for each screening technology.
The test apparatus used to evaluate the technologies allowed both the temperature and relative
humidity (RH) to be adjusted. For each technology, the test sequence of three clean air blanks
interspersed with three target gases was conducted under four different conditions (i.e., base
temperature and RH; elevated temperature and RH; low temperature and RH; and base temperature
and RH with an interferent, a mixture of hydrocarbons representative of polluted urban air). Testing
at the base temperature and RH was conducted first, and if a technology failed under this condition,
then no tests were conducted using the other three conditions.
Liguid Testing - For CWAs, testing was conducted for technologies and target agents in liquid
samples that were diluted in isopropyl alcohol (I PA) or deionized (Dl) water. The detection device
was tested with three blank samples of the solvent used (IPA or Dl water) and three samples of the
test solution containing the target agent. If a technology detected the chemical in at least one of the
three samples in the pure solvent, then the challenge was repeated with a hydrocarbon mixture
interferent (1% of the total volume) added to both the blank and challenge samples.
For TICs, samples were prepared in Dl water, in municipal tap water, and in Dl water containing 3.0%
sodium chloride by weight to simulate potential interfering sample matrices that might be encountered.
January 2009
EPA/600/S-09/015
This document does not constitute nor should be construed as an EPA endorsement of any particular product,
service, or technology.
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Each screening technology was tested with three blank samples and with three samples containing
the TICs. If the instrument failed to detect a TIC in all three challenge samples with the Dl water
matrix, then no tests were conducted with that TIC in tap or salt water.
Surface Testing - Testing was conducted for each technology using three blank glass coupons and
three glass coupons spiked with the nerve agent VX. All tests were conducted at room temperature
and approximately 50% relative humidity. For those technologies that correctly indicated the
presence of VX in at least one of these three tests, interference tests were then conducted by
spiking approximately 1 mg of interferent per coupon onto both the blank and VX-spiked coupons.
Additionally, for these same technologies, the blank and spiked coupon tests (without interferent)
were repeated at the same low and high temperature and relative humidity conditions used in the
vapor testing.
Test Results
Table 1 provides a summary of the detection capability of the screening technologies tested.
The following summarizes the testing information for each matrix form:
Vapor
Draeger Civil Defense Kit (CDK) detected 6 of 7 chemicals 100% of the time
Sensidyne Gas Detector Tubes detected 5 of 5 chemicals 100% of the time
Draeger Chip Measurement System (CMS) Analyzer, MSA Single CWA Sampler Kit,
and Nextteq Civil Defense Kit (CDK) detected 4 chemicals 100% of the time (out of 4, 5,
and 5 chemicals tested, respectively)
Anachemia CM256A1, Safety Solutions HazMat Smart-Stripฎ(SS), and Truetech M183A
detected 2 of 4 chemicals 100% of the time and Proengin AP4C detected 2 of 6 chemicals
100% of the time
Anachemia C2 and RAE Systems MultiRAE Plus detected 1 chemical 100% of the time
(out of 5 and 8 chemicals tested, respectively)
Smiths Detection APD2000ฎ did not detect either of the 2 chemicals tested 100% of the time.
Liquid
Due to the lack of acceptable results, samples that were diluted with isopropyl alcohol for CWA testing
were not factored into the Table 1 summary results. One explanation for the lack of acceptable results
may be that the technologies were not designed for application using non-aqueous solvents.
Truetech M272 Water Kit detected 3 of 3 chemicals 100% of the time
Severn Trent Services Eclox Strip detected 2 of 2 chemicals 100% of the time
Proengin AP4C and Safety Solutions HazMat Smart-Stripฎ detected 1 chemical 100% of
the time (out of 4 and 5 chemicals, respectively)
Anachemia C2, Anachemia CM256A1, and Nextteq CDK did not detect any chemical
100% of the time (3 chemicals tested).
Surface
All of the tested instruments detected the presence of VX 100% of the time, regardless
of temperature, relative humidity, or presence of interferent.
False Negatives and Positives
False negative results indicate that the screening technology was not able to detect the presence
of a chemical known to be present. This information is factored into the test results provided in
Table 1 and in the summary information above.
January 2009
EPA/600/S-09/015
This document does not constitute nor should be construed as an EPA endorsement of any particular product,
service, or technology.
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Testing for false positive responses was done using "clean" blank samples (i.e., clean air in the vapor
testing, pure solvents in the liquid testing, and a clean coupon in the surface testing) or interferent
blank samples (i.e., samples with the hydrocarbon mixture interferent, but without any test chemical
present). Few false positives occurred. The following summarizes these occurrences:
Vapor
False positive sarin responses occurred in all three interferent blank samples using Draeger
CDK and the MSA Single CWA Kit
One false positive sulfur mustard response occurred in the three interferent blank samples
using Smiths Detection APD2000ฎ.
Liquid
As indicated, false positives were observed only in the I PA blank samples, which was likely due
to incompatibility of the screening technologies with that solvent. Proengin AP4C, in particular,
responded positively to every I PA blank sample.
Surface
Two false positive responses occurred using the Proengin AP4C at the high temperature
and relative humidity condition.
Repeatability
Repeatability for the presence of TICs was tested for those instruments yielding quantitative results
(i.e., Draeger CMS Analyzer, RAE Systems MultiRAE Plus, and Sensidyne Gas Detector Tubes).
Quantitative results were recorded for each of the triplicate tests, and repeatability was calculated in
terms of percent relative standard deviation (% RSD). The following summarizes the test information:
32 of the 40 results had less than 15% RSD
Over half of the results (22 of 40) had less than 10% RSD
Several % RSD values exceeded 20% (e.g., Draeger CMS Analyzer for hydrogen
cyanide and chlorine).
Note: The PID principle of the MultiRAE Plus was not necessarily expected to respond to TICs or
CWAs tested as part of this evaluation (see Table 1); however, it was tested based on the
instrument's promotion as a general toxic compound detector.
Conclusions from this testing indicate that these instruments can provide reproducible results;
however, this cannot be assumed to be the case under different environmental conditions
(i.e., varying temperature and relative humidity) or with different concentrations.
Operational Information
Table 2 provides operational information on the 16 screening technologies tested. Information
included in the table includes:
Response time information (seconds or minutes to obtain an instrument response)
Ease of use
Response indication (e.g., detection is indicated by color change)
Initial cost.
Response and Ease of Use Information
The speed and simplicity of the vapor screening process varied widely among the tested
technologies. Ease of use was not necessarily correlated with instruments' detection capabilities. The
following provides some general highlights on response time and ease of use for each sample matrix:
January 2009
EPA/600/S-09/015
This document does not constitute nor should be construed as an EPA endorsement of any particular product,
service, or technology.
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Vapor
Color-indicating tube technologies were simple to use in principle, but differed in the time
and difficulty of obtaining samples.
o The number of manual pump strokes required to draw in the air sample ranged widely,
as did the manual effort needed for those technologies requiring multiple pump strokes.
o Nextteq CDK used an electric air sampling pump that greatly reduced the physical effort
needed; however, it still required a few minutes to draw the required sample volume.
The three real-time technologies tested (RAE Systems MultiRAE Plus, Proengin AP4C, and
Smiths Detection APD2000ฎ) provided easy and rapid sample analysis for chemicals in vapor;
however, there was a wide range in instruments' detection capability.
Safety Solutions HazMat Smart-Stripฎ was the simplest technology, requiring only removal of
a protective film to expose the indicating patches on the card. The detection response occurred
within seconds.
Color-indicating tubes that require the minimum sample volume are preferable for use in
AHRFs. Additionally, the use of an electrical sampling pump is helpful if a large numbers
of samples are to be screened.
Liquid and Surface
For surface samples, M8, M9, and 3-way indicating papers were especially easy to use
and responses typically occurred within seconds.
For liquid samples, Severn Trent Services Eclox Strip and Truetech M272 Water
Kit were relatively easy to use and responses occurred within minutes.
Analysis of liquid and surface samples with Proengin AP4C was relatively rapid because
the detector's attachments were simple to use.
During homeland security events, it would be important for the technologies to screen for multiple
chemicals simultaneously. Technologies using multiple color-indicating tubes at once provide this
capability. Proengin AP4C provided multi-chemical detection and could be used to detect chemicals
in vapor, liquid, and surface samples.
Cost
The initial cost of the technologies varied substantially, ranging from a few hundred to a few thousand
dollars. The two exceptions were Proengin AP4C at a discounted cost of nearly $16,000 and Smiths
Detection APD2000ฎat a cost of $10,000. Comparing purchase prices of different technologies can
be misleading. Many of the technologies can screen relatively few samples with the originally supplied
materials. For example, several technologies that rely on color-indicating tubes initially come with
only enough tubes to screen 10 to 40 samples. Testing larger numbers of samples requires additional
tubes. All technologies tested require consumable items such tubes and batteries. Simple test papers
are the least expensive, with costs estimated at less than $0.50 per sample. Most technologies tested
had similar costs per sample, typically ranging from $4 to $20 per sample.
For more information about the technologies evaluated for use in AHRFs, or by first responders,
visit the NHSRC Web site at www.epa.qov/nhsrc, or view the full reports, Testing of Screening
Technologies for Detection of Chemical Warfare Agents in All Hazards Receipt Facilities at
www.epa.qov/nhsrc/pubs/600r07104.pdf and Testing of Screening Technologies for Detection
of Toxic Industrial Chemicals in All Hazards Receipt Facilities at
www.epa.gov/nhsrc/pubs/600r08034.pdf.
Principal Investigator: Eric Koglin
Feedback/Questions: Kathy Nickel (513) 569-7955
January 2009
EPA/600/S-09/015
This document does not constitute nor should be construed as an EPA endorsement of any particular product,
service, or technology.
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