testing of apd2000 chemical warfare agent detector against
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1. 65 0 1 Diesel 17 02570 BlisterH 56 BlisterH 60 Laboratory evaluations to determine if other potential interferent compounds would cause the detector to false alarm are summarized in Table 5 If an alarm occurred at the 1 saturation level the interferent was reduced to 0 1 saturation and tested again These tests were conducted without using the CW agents Detectors A and B both alarmed for 8 out of 12 substances tested at the 1 concentration level The false alarm rates were less frequent at the 0 1 concentration level Those substances that did not cause false alarms at the 1 level were not further tested at the 0 1 level Nevertheless detector A false alarmed for 4 out of 9 tests and detector B false alarmed for 2 out of 9 of the interferents tested at 0 1 concentration Table 5 Average Results of Laboratory Interference Tests without Agents Reference Levels Reference Levels 6 CONCLUSIONS The APD2000 detectors have demonstrated CW agent vapor detection for HD GA and GB The minimum detectable levels for the CW agents tested are approximately an order of magnitude better than the current military JSOR sensitivity requirements for a point sampling alarm The two detector units produced consistently similar responses at all conditions tested The ability to detect agent in the presence of an interfering vapor when the vapor itself does not cause a false alarm has been demonstrated Civilian first responder2. problems The detectors were difficult to start and the LCD display was extremely difficult to read In one case unit A failed to power up in the cold temperature and unit C had to be used for that test Table 2 Alarm Responses at Various Temperatures and Relative Humidity Conditions APD2000 Detector A APD2000 Detector B Average Relative Concentratio Alm Time Alan Time ENT Temperature Humidity Reference Reference A Agent Class Range P Agent Class Range Cc Units Units seconds seconds 0 22 1 49 2 16 55 2 20 1 89 1 81 1 68 un f ro m mr Tea ss es om ee 65 100 100 100 gt co 65 65 100 68 SEC ETE 56 METAN T 5 8 a 0 02 0 100 9 22 0 100 0 112 0 110 0 08 N Nerve VX Nerve GA tH jewe ene GA eves jenes En co co D 20 lt 5 2o lt 5 20 lt 5 eo lt 5 20 50 2o gt 90 o o so lt 5 a ADN zo lt 5 20 lt 5 eo lt 5 20 50 2o gt 90 30 0 so lt 5 APD2000 Detector A APD2000 Detector B Average Relative Concentratio Karma Alam Tine AGENT Temperature Humidity Reference Reference 5 3 Agent Class Range Agent Class Range C Units Units seconds seconds f o fe 000 E O E vates T retose a 0037 vater totes meses 30 nenese 56 05 cB 0008 50 tenes 1681 a0 tenes 1621 cB cB 0 14 60 Nenecs 16 20 50 Nenecs 15
3. 20 GB 90 007 45 NevecB 16 19 35 NeneGB 16 21 GB 0 06 so ce 1417 30 GB 1525 lt 5 008 45 NemeGs 19 21 35 NeneGB 17 23 UnitA TTF with AP D2000 C for this test Bist blister agent e e 5 3 FIELD INTERFERENCE The detector false alarm results for the field test interferent exposures are presented in Table 3 False alarms indicate that the detector alarmed in the absence of CW agent The ambient temperature and relative humidity levels during these tests were in the range of 26 36 C and 53 91 RH with gentle wind Detector A was replaced with Detector C during the field testing due to frequent VX false alarms The field test false alarm rate showed that both detectors false alarmed one out of three trials for the JP8 vapor and AFFF vapor The displays showed VX and GD for detectors B and C respectively for JP8 For AFFF the displays showed VX and GA for detectors B and C respectively The other field test interferents did not cause the detectors to alarm Post field test responses against HD and GA showed the APD2000 detectors to have no adverse residual effects from the field tests The units alarmed for the agents with similar response levels after the field tests when evaluated against HD and GA at similar pre field test conditions Table 3 Field Interference Testing Summary APD2000 Detectors B and C One minute interferent exposures Alarms Trials Alarms Trials Display Re
4. Agents cssccsssseees 10 Average Results of Laboratory Interference Tests without Agents 10 FIGURE APD 2000 A hun 3 Blank DOMESTIC PREPAREDNESS PROGRAM TESTING OF APD2000 CHEMICAL WARFARE AGENT DETECTOR AGAINST CHEMICAL WARFARE AGENTS SUMMARY REPORT 1 INTRODUCTION The Department of Defense DOD formed the Domestic Preparedness DP Program in 1996 in response to Public Law 104 201 One of the objectives is to enhance federal state and local capabilities to respond to Nuclear Biological and Chemical NBC terrorism incidents Emergency responders who encounter a contaminated or potentially contaminated area must survey the area for the presence of toxic or explosive vapors Presently the vapor detectors commonly used are not designed to detect and identify chemical warfare CW agents Little data are available concerning the ability of these commonly used commercially available detection devices to detect CW agents Under the Domestic Preparedness DP Expert Assistance Test Equipment Program the U S Army Soldier and Biological Chemical Command SBCCOM established a program to address this need The Design Evaluation Laboratory DEL at Aberdeen Proving Ground Edgewood Maryland performed the detector testing DEL is tasked with providing the necessary information to aid authorities in the selection of detection equipment applicable to their needs Several detectors were evaluated and reported durin
5. capable of responding consistently to very low concentrations of the CW agents tested as indicated by the similar results of detectors A and B Army regulation AR 385 61 does not establish an IDLH for HD due to concerns over carcinogenicity The APD2000 units would not detect at the AEL levels Table 1 Minimum Detectable Level MDL at Ambient Temperatures and Low RH Concentration in milligrams per cubic meter mg m With parts per million values in parenthesis ppm 0 220 0 220 2 0 0 003 0 033 0 033 0 300 0 0005 AGENT er 0 027 0 027 0 1 0 2 0 0001 0 004 0 004 0 015 0 03 0 000015 aa 0 021 0 037 0 1 0 2 0 0001 0 004 0 006 0 017 0 03 0 000017 Joint Service Operational Requirements for point sampling detectors Immediate Danger to Life or Health values from AR 385 61 to determine level of CW protection Personnel must wear full ensemble with SCBA for operations or full face piece respirator for escape Airborne Exposure Limit values from AR 385 61 to determine masking requirements Personnel can operate for up to 8 hours unmasked 5 2 TEMPERATURE AND HUMIDITY EFFECTS Table 2 lists the average responses of the APD2000 detectors at various test conditions Tests were conducted at ambient temperatures and RH conditions of approximately 0 50 and 90 The 6 AG I U i ee II II SS 2222 1515 5151010 5 O gt detectors were also tested at temperature extremes of 30 C 0 C for HD
6. solid sorbent contained in a glass tube referred to as the pre concentrator tube PCT The PCT is located after the MINICAMSO inlet Here the concentrated sample is periodically heat desorbed into a gas chromatographic capillary column for subsequent separation identification and quantification For manual sample collection the PCT was removed from the MINICAMS during the sample cycle and connected to a measured suction source to draw the vapor sample from the agent generator The PCT was then re inserted into the MINICAMS for analysis This manual sample collection procedure eliminates potential loss of sample through sampling lines and the inlet assembly in order to use the MINICAMS as an analytical instrument The calibration of the MINICAMS was performed daily using the appropriate standards for the agent of interest 4 5 FIELD INTERFERENCE TESTS Upon completion of the agent sensitivity tests the detectors were tested outdoors in the 4 presence of common potential interferents such as the vapors from gasoline diesel fuel jet propulsion fuel JP8 kerosene AFFF liquid Aqueous Film Forming Foam used for fire fighting household chlorine bleach and insect repellent Vapor from a 10 HTH slurry a chlorinating decontaminant for CW agents engine exhausts burning fuels and other burning materials were also tested The field tests were conducted outdoors at M Field of the Edgewood Area of Aberdeen Proving Ground in July 19
7. 00 CHEMICAL WARFARE AGENT DETECTOR AGAINST CHEMICAL WARFARE AGENTS None SUMMARY REPORT 6 AUTHOR S Ong Kwok Y Longworth Terri L Barnhouse Jacob L 7 PERFORMING ORGANIZATION NAME S AND ADDRESS ES 8 PERFORMING ORGANIZATION REPORT NUMBER DIR ECBC ATTN AMSSB RRT APG MD 21010 5424 ECBC TR 9 SPONSORING MONITORING AGENCY NAME S AND ADDRESS ES 10 SPONSORING MONITORING AGENCY REPORT NUMBER Program Director Domestic Preparedness 5183 Blackhawk Road ATTN AMSSB RTD APG MD 21010 5424 11 SUPPLEMENTARY NOTES 12a DISTRIBUTION AVAILABILITY STATEMENT 12b DISTRIBUTION CODE Approved for public release distribution is unlimited 13 ABSTRACT Maximum 200 words This report characterizes the chemical warfare CW agent detection potential of the commercially available APD2000 Chemical Agent Detector These detectors were tested against HD GB and GA vapor at various conditions This report is intended to provide the emergency responders concerned with CW agent detection an overview of the detection capabilities of these detectors 14 SUBJECT TERMS 15 NUMBER OF PAGES HD Vapor testing Chemical Warfare Agent Detection GB Detector testing Field and Laboratory Interferences 12 GA Interferent Testing 17 SECURITY CLASSIFICATION OF 18 SECURITY CLASSIFICATION 19 SECURITY CLASSIFICATION OF 20 LIMITATION OF ABSTRACT REPORT OF THIS PAGE ABSTRACT UNCLASSIFIED UNCLASSIFIED UNCLASSIFIED UL NSN 7540 01 280 5500 Stand
8. 99 The detectors were placed at various distances downwind of the open containers truck engines or fires for example 1 3 meters for vapor fumes and 2 5 meters for smokes depending on wind direction and velocity at test time The objective was to assess the ability of the detectors to withstand outdoor environments and to resist false positive alarm indications when exposed to the selected potential interference substances A confidence check was performed on each detector at the beginning of each testing day Particulate nozzle filters were used during smoky exposures as suggested in the User s manual Two APD2000 units were exposed to each interferent for three trials of one minute exposure per trial with approximately five minutes clear down time between trials After the third trial confidence sample checks were conducted If the sensitivity deteriorated the detectors were allowed more clear out time Testing continued with the next challenge approximately 5 minutes after the detectors had cleared 4 6 LABORATORY INTERFERENCE TESTS These tests were designed to assess detector response to vapor from representative substances and to show the CW agent detection capability of the detectors in the presence of the potential interference vapors from AFFF and diesel fuel The interferents were chosen based on the likelihood of their presence during an emergency response by first responders The APD2000 detectors were tested against 1
9. ECBC TR HHHH DOMESTIC PREPAREDNESS PROGRAM TESTING OF APD2000 CHEMICAL WARFARE AGENT DETECTOR AGAINST CHEMICAL WARFARE AGENTS SUMMARY REPORT Kwok Y Ong Terri L Longworth Jacob L Barnhouse Research Directorate August 2000 Approved for public release distribution is unlimited Soldier and Biological Chemical Command AMSSB RRT Aberdeen Proving Ground MD 21010 5424 Disclaimer The findings in this report are not to be construed as an official Department of the Army position unless so designated by other authorizing documents REPORT DOCUMENTATION PAGE Public reporting burden for this collection of information is estimated to average hour per response including the time for reviewing instructions searching existing data sources gathering and maintaining the data needed and completing and reviewing the collection of information Send comments regarding this burden estimate or any other aspect of this collection of information including suggestions for reducing this burden to Washington Headquarters Services Directorate for Information Operations and Reports 1215 Jefferson Davis Highway Suite 1204 Arlington VA 22202 4302 and to the Office of Management and Budget Paperwork Reduction Project 0704 0188 Washington DC 20503 1 AGENCY USE ONLY Leave Blank 2 REPORT DATE 3 REPORT TYPE AND DATES COVERED pam boone PP rm eyo 4 TITLE AND SUBTITLE 5 FUNDING NUMBERS DOMESTIC PREPAREDNESS PROGRAM TESTING OF APD20
10. Public Health Ann Arbor MI Leo F Saubier Battelle Memorial Institute Edgewood MD Blank iV 4 1 4 2 4 3 4 4 4 5 4 6 5 1 5 2 5 3 5 4 oe CONTENTS INTRODUCTION usina rca 1 OBJECTIVE nenne 1 SLO d DA A AS EE A E E E EA 1 EQUIPMENT AND TEST PROCEDURES s0sc0sssssesssssessonsnnssnnssnnsnsnssnssonsnunene 2 DETECTOR DESCRIPTION 2 CALIBBATION 22a Eee 3 AGENT CHALLENGE ui 3 AGENT VAPOR QUANTIFICATION 20s000s000000s0000000000n000n00n00nnennnn0n 4 FIELD INTERFERENCE TESTS 00s000000000002002000200n000000000002000000200n00n00000 4 LABORATORY INTERFERENCE TESTS 2 200000000000000000000020000200000000 5 RESULTS AND DISCUSSION ocisssissssiessscsonssedisecesondecnatincesivesiacsnstedtunssseudeuastencesaes 6 MINIMUM DETECTABLE LEVEL 00s00s000s0nsesnsssossonssnssnnssnunnsessnssonsnnne 6 TEMPERATURE AND HUMIDITY EFFECTS ccsccsssssssscssscssscssscessees 6 FIELD INTERFERENCE u u sss005400800 00er nennen naeh 8 LABORATORY INTERFERENCE TESTS scsscssssssscssssssssccssceseseeees 9 EONTCLUSIONS u eins 10 LITERATURE CITED u ee ii ias 102 TABLES Minimum Detectable Level MDL at Ambient Temperatures and Low RH 6 Alarm Responses at Various Temperatures and Relative Humidity Conditions 7 Field Interference Testing Summary 0 cs00s00000s00000s00000000000200000000000000000 cocoa 000000000 8 Average Results of Laboratory Interference Tests with
11. ading Unit B Unit C B C Gasoline Exhaust de w Noe Gasoline Exhaust Rewed APD2000 Detectors B and C One minute interferent exposures Alarms Trials Alarms Trials Display Reading Unit B Unit C B C Burning JP8 Smoke oa Nome Burning Gasoline Smoke Burning Diesel Smoke AFFF Vapor o f ne insect Repellent oo f Noe Diesel Vapor 8 Noe Gasoline Vapor Noe HTA Vapor Noe lead Vapor OB Noe Burning Cardboard wo oo Noe Burning Cotton o o Noe Buming Wood Fre Smoke wo o Nome Doused Wood Fire Smoke Nme Burning Rubber o o Moe Detector A was unsuccessfully used during these trials and removed from field test for continuous electronic noise VX false alarms Detector C replaced it for the remainder of the field tests 5 4 LABORATORY INTERFERENCE TESTS Table 4 presents the results of testing the detectors with conditioned air containing GA GB or HD in the presence of diesel fuel vapor or AFFF vapor The detectors A and B were able to detect and identify the CW agents in the presence of these interferents Table 4 Average Results of Laboratory Interference Tests with Agents agent Interterem _Goneentration _ __eferente Lev a3 O1 AFFF 0 07 0 0104 NeweGA 60 NeweGA 50 0 1 Diesel 0 1 0 0148 NeweGA 60 NeweGA 50 65 OI AFFF 007 0 0120 NeweGB 50 NeweaB 45 0 1 Diesel HD O1AFFF 17 02570 BisterH 70 BlsterH
12. and 50 C The APD2000 detectors successfully demonstrated CW agent detection at various temperature and humidity conditions Most of the alarm and clear down times occurred within 30 seconds of agent exposure The minimum detectable levels were approximately an order of magnitude lower than the current JSOR and IDLH standards The reference level readings are also shown in Table 2 Larger numbers indicate the presence of higher concentration of vapor is suspected The numeric values 26 50 51 75 and 76 100 are relative indications for low medium and high agent concentration responses respectively Values below 25 are below the alarm threshold The reference class for this detector response is nerve or blister with or without a specific agent GA GB GD VX HD HN or L identified Unfortunately the specific identification response of the detector did not always correspond to the actual challenge CW agent because of overlapping of ion mobility spectrometry peaks The detector would alarm but the reference indication was incorrect For example the detectors alarmed and indicated Blister and Nerve VX as well as Nerve GA during the GA tests GB evaluations sometimes indicated Nerve VX instead of Nerve GB In addition the HD tests showed a variety of indications including Blister L and Nerve VX as well as the correct Blister H response In the cold temperature 30 C only the detectors had power and LCD display visibility
13. ard Form 298 Rev 2 89 Prescribed by ANSI Std Z39 18298 102 Blank PREFACE The work described herein was authorized under the Expert Assistance Equipment Test Program for the U S Army Soldier and Biological Chemical Command SBCCOM Program Director for Domestic Preparedness This work was started in May 1999 and completed in July 1999 The use of either trade or manufacturers names in this report does not constitute an official endorsement of any commercial products This report may not be cited for purposes of advertisement This report has been approved for public release Registered users should request additional copies from the Defense Technical Information Center unregistered users should direct such requests to the National Technical Information Service Acknowledgments The authors acknowledge Juan C Cajigas and Marcia A Johnson for their assistance in performing agent testing In addition we thank Frank DiPietro and Robert S Lindsay for their assistance in test planning acquisition and review The authors are grateful to the following members of the Expert Review Panel for Equipment Testing for their constructive reviews and comments Dr Jimmy Perkins University of Texas School of Public Health San Antonio TX Dr Bruce A Tomkins Ph D Organic Chemistry Section Chemical and Analytical Sciences Division Oak Ridge National Laboratory Oak Ridge TN Dr Edward T Zellers University of Michigan School of
14. concentrations of gasoline JP8 diesel fuel household chlorine bleach floor wax AFFF Spray 9 cleaner Windex antifreeze toluene vinegar and 25 PPM ammonia to observe potential interference with the detection reaction process If the detector false alarmed at 1 it was tested against an 0 1 concentration of each interferent To prepare the interferent test gas mixture dry lt 5 RH air at 20 C was saturated with interferent vapor by passing it through the interferent liquid in a bubbler or by sweeping it over the liquid contained in a tube Thirty milliliters of this vapor saturated air was then diluted to three liters of the conditioned air to produce the 1 concentration of interferent In the same manner a 0 1 concentration of interferent was produced using three milliliters of vapor saturated air diluted to three liters of generator air to further test the detector if the detector false alarmed at the higher concentration The 25 ppm ammonia was derived by proper dilution of the 1 NH vapor from an analyzed compressed gas cylinder The dilution levels were chosen to represent possible occurrences in CW protective shelters The CW agent detection capability of the detectors in the presence of the potential interference vapors from AFFF and diesel fuel was assessed The test gas mixture was prepared by using air 20 C lt 5 RH that was saturated with either diesel fuel or AFFF Three milliliters of the vapor saturated air was d
15. g Phase 1 testing in 1998 Phase 2 testing in 1999 continues the evaluation of detectors including the MIRAN SapphIRe Portable Ambient Air Analyzer MSA tubes the M90 D1 C Chemical Warfare Agent Detector and the APD2000 Detector Zo OBJECTIVE The objective of this test is to assess the capability and general characteristics of the APD2000 Detector to detect chemical warfare agent vapors This report is one of several reports on the Phase 2 evaluations of detectors conducted during 1999 The intent is to provide the emergency responders concerned with CW agent detection an overview of the detection capabilities of the detectors 3 SCOPE This evaluation attempts to characterize the CW agent vapor detection capability of the APD2000 detector The agents used included Tabun GA Sarin GB and Mustard HD These were considered representative CW agents because they are believed to be the most likely threats Test procedures followed those described in the Phase 1 Test Report The test concept was as follows a For each selected CW agent determine the minimum concentration levels Minimum Detectable Level MDL where repeatable detection readings are achieved The military Joint Services Operational Requirements JSOR for point sampling detectors served as a guide for detection sensitivity objectives b Investigate the humidity and temperature effects on detector response c Observe the effects of potential interfering vapors upon de
16. iluted to three liters with the 20 C lt 5 RH conditioned air containing a prescribed concentration of CW agent from the agent generator to produce the 0 1 concentration of interference mixture The two APD2000 detectors were tested three times with each agent interferent 5 mixture and the detection responses were recorded 5 RESULTS AND DISCUSSION 5 1 MINIMUM DETECTABLE LEVEL The minimum detectable level MDL for the APD2000 detectors A and B are shown in Table 1 for each agent at ambient temperatures and low relative humidity lt 5 RH The MDL was established by lowering the agent concentrations until there was no response from the detectors The MDL values were selected based on the lowest CW agent concentration exposure to produce alarms consistently for three trials The MDL concentrations are expressed in mg m and the equivalent parts per million ppm values are shown The current military requirements for CW agent detection Joint Service Operational Requirements JSOR for CW agent sensitivity for point detection alarms the Army s established values for Immediate Danger to Life or Health IDLH and the Airborne Exposure Limit AEL are also listed as references to compare the detector s performance When compared to the JSOR and IDLH values the MDLs of the APD2000 units for the CW agents tested are all approximately an order of magnitude lower Lower MDL represents better detection sensitivity These detectors are
17. lost communication It had to be re set to correct this problem Initially Unit A did not have electronic false alarms It showed such false alarms as testing progressed During field testing at M Field Unit A false alarmed so much that it had to be removed from testing e Itis believed that the false alarms occurred during the field tests because the detector s internal temperature reached 50 degrees C The false alarms decreased enough to allow further testing when returned for lab tests at 25 degrees C but did not disappear completely It is possible that the higher temperature aggravated this problem APD2000 detectors at ETG were examined and it was found that a connection was not properly soldered It is thought that this would contribute to electronic noise e Unit A would not start up at 30 degrees C Examination of detectors at ETG that had the same problem revealed that the watchdog timer was resetting and thus not allowing the unit to start up This problem was corrected by changing the software so that the timing was made compatible with the watchdog timer to allow for timing variations caused by different temperatures 11 e High 5 to 8 mg m concentration GA either alarmed as only Blister or Blister and GA or only alarmed when the challenge was removed from the detector Recommendation is to change the GA agent classifier to improve GA detection e The High Voltage HV appears to be out of its specified range The
18. manufacturing processes need to be updated to verify HV at the board level compares to the HV numbers output in the log data If the problems are correctable as indicated in the manufacturer s comments the APD2000 offers features that would be useful for first responders applications The detectors provided consistent CW detection sensitivity and the additional visual display information at less than alarm level indications is a plus However the high false alarm rates 8 of 12 substances tested observed in the laboratory interference tests are of a major concern This indicates that during an operation using the APD2000 alarms very likely could be false indications of a detected threat Literature Cited Longworth Terri L et al Testing of Commercially Available Detectors Against Chemical Warfare Agents Summary Report ECBC TR 033 U S Army Chemical Research and Engineering Center Aberdeen Proving Ground MD May 1999 UNCLASSIFIED Report 2 APD2000 User s Manual Environmental Technologies Group Inc Baltimore MD August 1998 3 Ong Kwok Y Multi Purpose Chemical Agent Vapor Generation System ERDEC TR 424 U S Army Chemical Research and Engineering Center Aberdeen Proving Ground MD July 1997 UNCLASSIFIED Report j Ong Kwok Y et al Analytical Methodology for Quantitative Determination of O ethyl S 2 Diisopropylaminoethyl Methylphosphonothiolate VX ERDEC TR 476 U S Army Chemical Research and E
19. ngineering Center Aberdeen Proving Ground MD March 1998 UNCLASSIFIED Report gt Extracted from correspondence with Dr G Lozos of ETG via email to Kwok Ong dated 12 October 1999 12
20. nts The mode button is then pressed until READY CW appears on the display and the detector is ready for use 43 AGENT CHALLENGE The agent challenges were conducted using the Multi Purpose Chemical Agent Vapor Generation System with Chemical Agent Standard Analytical Reference Material CASARM grade CW agents The vapor generator permits preconditioning of a detector with humidity and temperature 3 conditioned air before challenging it with similarly conditioned air containing the CW agent Agent testing followed successful detector start up First conditioned air at the desired temperature and humidity from the vapor generator system was sampled by the detector for approximately one minute to establish the stable background of the detector for the air at each condition Agent challenge began when the solenoids of the vapor generation system were energized to switch the air streams from the conditioned air only to the similarly conditioned air containing the agent Each detector was tested three times under each condition The time that the detector was exposed to the agent vapor until it alarmed was recorded as the alarm time The time for clear down after the agent challenge was also noted This is the time required for the detector to stop alarming after the agent vapor flow ends The detectors were each tested with the agents GA GB and HD at different concentration levels at ambient temperature and low lt 5 relative humidity in an a
21. operational temperature range from 22 F to 126 F 30 C to 52 C and the relative humidity range from zero to 95 Battery life decreases sharply at lower temperatures DC power supply was used through the evaluation to ensure that the detector performance would not be affected by battery condition Figure is a digital photograph of the APD2000 detector Three detectors were purchased for this evaluation and randomly labeled A B and C Detectors A and B were used during the evaluations and C was reserved for a backup when necessary Figure 1 APD2000 Detector 4 2 CALIBRATION Operating procedures were followed according to the Users Manual No daily instrument calibration is required to place the APD2000 detector into operation After the power button is pressed the detector completes a self test and goes into standby mode This startup procedure takes approximately three minutes The detection performance is verified daily using the confidence test sampler provided with the detectors by the manufacturer In order to perform the confidence check the detector mode must be changed by pressing the mode button until READY TEST appears on the display One end of the confidence test sampler contains the simulant for blister agent and is labeled as H The other end contains a simulant for nerve agent and is labeled G If the detector is working properly an alarm will occur within seconds after exposure to each of these simula
22. orrectly display the wrong agent or wrong class of agent detected During interferent tests the detectors alarmed to Nerve VX and Blister L for most of the false alarms These false alarms and the frequency of alarms that occurred during the laboratory testing of the potential interferents cause concern Results indicate that despite the low false alarm rate observed in the field interference tests the units are subject to more frequent alarms to many potential interference vapors when challenged in the laboratory under a more controlled and persistent exposure at 1 concentrations Following the detector evaluations the manufacturer performed troubleshooting of the problems encountered during the testing This was allowed because the detector showed CW agent sensitivity They have offered the following explanations and possible corrective solutions e At the beginning of this evaluation Unit B frequently false alarmed The cause was determined to be bad power communications cable and or connector cap that created numerous random peaks These problems disappeared when the power cable was removed and the unit was operated on batteries After removing the auxiliary connector a wire was found clamped under the connector This was corrected and false alarms due to electric noise disappeared The unit can now be operated using the power cable e Unit B showed communications problems with the optional personal computer link Several times the unit
23. s a number between zero and 100 for the specific CW agent or the class of CW agent that caused the detector to alarm Larger numbers indicate the presence of a higher concentration of vapor is suspected The numeric values 26 50 51 75 and 76 100 are relative indications for low medium and high agent concentration responses respectively and will trigger the audio alarm Response value below 25 indicates there is a detection of the displayed substance at low concentration levels below the alarm set point The audio alarm will not sound when below the threshold set point The reference class for this detector response can be either nerve or blister with or without a specific agent GA GB GD VX HD HN or L identified This feature despite occasional mislabels distinguishes this detector from others tested thus far The detector also contains a back flush pump that reverses the sample flow path to protect the cell assembly from gross contamination Back flush mode is activated when the detector displays a high 76 100 concentration detection The detector cannot detect when it is in this back flush mode until its sensor has been sufficiently purged Power sources to operate the APD2000 include six standard or rechargeable C batteries AC adapter or 9 18 Volt DC supply Six C type batteries can sustain approximately seven hours of operation at ambient temperature The APD2000 operating specifications give the
24. s and HAZMAT personnel are using Immediate Danger to Life or Health IDLH values to determine levels of respiratory protection selection during consequence management of an incident Army Regulation AR 385 61 gives IDLH and Airborne Exposure Limit AEL values for GB GA and an AEL value for HD AR 385 61 does not establish an IDLH for HD due to concerns over carcinogenicity 10 The APD2000 detectors demonstrated detection of G agents to their IDLH values at all temperature and humidity conditions tested however are unable to detect to the AEL values for HD GA or GB Several problems arose during the evaluations Specifically cold temperature 30 C only operation caused excessive power consumption and the inability to read the display The use of c type batteries did not provide sufficient operational power The inability to read the display panel made it impossible to get the detector into proper operational mode Thus the DC power supply was used through the evaluation to ensure that the detector performance would not be affected by battery condition In the cold temperature testing the detectors could only be started with the computer connected The automatic backflush feature disabled detection capability when it occurred In addition during the CW agent sensitivity tests several false alarms at the reference levels Nerve or Nerve VX were observed while awaiting agent testing Throughout the evaluation the units alarms would inc
25. tector performance both in the 1 field and in the laboratory 4 EQUIPMENT AND TEST PROCEDURES 4 1 DETECTOR DESCRIPTION Environmental Technologies Group Inc ETG manufactures the APD2000 detectors The detector is marketed as a lightweight approximately 6 pounds including the batteries handheld portable detector designed for surveying the environment to identify specific CW agents and irritants It contains a 10 millicurie Nickel 63 radioactive source The detector can be operated in CW or irritant mode For this evaluation only the CW agent mode was considered The APD2000 detects nerve and blister agents simultaneously in its CW mode It also has data logging features to record monitoring events The APD2000 employs ion mobility spectrometry IMS detection techniques Sample air passes through the heated membrane and then is drawn into the cell assembly The molecules are ionized by the radiation source The resulting ions are swept down the drift tube where they become separated according to their mass and mobility toward the collector electrode An electronic signature is produced for each ion based on the time required to reach the collector electrode The APD2000 will sound an alarm if the sample signal matches the required signature criteria In addition to the audible alarm the detector also has a visible display that shows reference level readings and the identity of the substance detected The reference level i
26. ttempt to determine the mintmum detectable level MDL and response characteristics Additionally the detectors were tested at relative humidity conditions of 50 and 90 as well as the temperature extremes of 30 C GA and GB 0 C for HD and 50 C GA GB and HD to observe temperature and humidity effects The sensitivity effects of relative humidity and air temperature on the detector responses were observed during tests using agent concentrations that were slightly higher than the MDL The tests were conducted within the operating range of the detectors HD was only tested down to 0 C due to its physical property limitations Although HD freezes at approximately 15 C it has a volatility of 92 mg m at 0 C that is considered potentially hazardous It should be noted that 0 C is lower than the current JSOR that only requires HD detection down to 15 C 4 4 AGENT VAPOR QUANTIFICATION The generated agent vapor concentrations were analyzed independently and reported in mg m The vapor concentration was quantified by the manual sample collection methodology using the Miniature Continuous Air Monitoring System MINICAMS manufactured by O I Analytical Inc Birmingham Alabama The MINICAMS is equipped with a flame photometric detector FPD and operated in phosphorus mode for the G agents and sulfur mode for HD This system normally monitors air by collection through sample lines and subsequently adsorbing the CW agent onto the
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