5.1 General—Hydrogen sulfide is nearly ubiquitous. It occurs naturally in volcanic gases, in sulfur springs and fumaroles, in decaying of plant and animal protein, and in intestines as a result of bacterial action. Hydrogen sulfide is a serious hazard to the health of workers employed in energy production from hydrocarbon or geothermal sources, in the production of fibers and sheets from viscose syrup, in the production of deuterium oxide (heavy water), in tanneries, sewers, sewage treatment and animal waste disposal, in work below ground, on fishing boats, and in chemical operations, including the gas and oil industry.5.2 In 29 CFR 1910.1000, the Federal Occupational Safety and Health Administration designates that worker exposure to certain gases and vapors must not be exceeded in workplace atmospheres at concentrations above specific values, averaged over a certain time span. Hydrogen sulfide is included in this list. Refer also to NIOSH Criteria for a Recommended Standard, Occupational Exposure to Hydrogen Sulfide.5.3 This practice will provide means for the determination of airborne concentrations of hydrogen sulfide.5.4 This practice provides means for either personal or area sampling and for short-term or time-weighted average (TWA) measurements. Refer to Threshold Limit Values for Chemical Substances in the Work Environment.1.1 This practice covers the detection of hydrogen sulfide gas by visual chemical detectors. Included under visual chemical detectors are: short-term detector tubes (1),2 long-term detector tubes (2), and length-of-stain dosimeters (3). Diffusion tubes are not included under this practice because they are not direct reading, and spot tests are not included because of their poor accuracy. The sample results are immediately available by visual observation, thus no analytical equipment is needed.1.2 This practice reflects the current state-of-the-art for commercially available visual length-of-stain detectors for hydrogen sulfide. Any mention of a specific manufacturer in the text or references does not constitute an endorsement by ASTM.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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3.1 Although it is possible to observe and measure each of the several characteristics of the ELCD under different and unique conditions, in particular its different modes of selectivity, it is the intent of this practice that a complete set of detector specifications should be obtained at the same operating conditions, including geometry, gas and solvent flow rates, and temperatures. It should be noted that to specify a detector's capability completely, its performance should be measured at several sets of conditions within the useful range of the detector. The terms and tests described in this practice are sufficiently general so that they may be used at whatever conditions may be chosen for other reasons.3.2 Linearity and speed of response of the recorder used should be such that it does not distort or otherwise interfere with the performance of the detector. Effective recorder response should be sufficiently fast so that it can be neglected in sensitivity of measurements. If additional amplifiers are used between the detector and the final readout device, their characteristics should also first be established.1.1 This practice covers testing the performance of an electrolytic conductivity detector (ELCD) used as the detection component of a gas chromatographic system.1.2 This practice is directly applicable to electrolytic conductivity detectors that perform a chemical reaction on a given sample over a nickel catalyst surface under oxidizing or reducing conditions and employ a scrubber, if needed, to remove interferences, deionized solvent to dissolve the reaction products, and a conductivity cell to measure the electrolytic conductivity of ionized reaction products.1.3 This practice covers the performance of the detector itself, independently of the chromatographic column, in terms that the analyst can use to predict overall system performance when the detector is coupled to the column and other chromatographic system components.1.4 For general gas chromatographic procedures, Practice E260 should be followed except where specific changes are recommended herein for the use of an electrolytic conductivity detector. For definitions of gas chromatography and its various terms see Practice E355.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Although it is possible to observe and measure each of the several characteristics of a detector under different and unique conditions, it is the intent of this practice that a complete set of detector specifications be obtained at the same operating conditions, including geometry, flow rates, and temperatures. To specify a detector's capability completely, its performance should be measured at several sets of conditions within the useful range of the detector. The terms and tests described in this practice are sufficiently general so that they may be used under any chosen conditions.4.2 Linearity and speed of response of the recorder should be such that it does not distort or otherwise interfere with the performance of the detector. Effective recorder response should be sufficiently fast so that its effect on the sensitivity of measurement is negligible. If additional amplifiers are used between the detector and the final readout device, their characteristics should first be established.1.1 This practice covers testing the performance of a nitrogen/phosphorus thermionic ionization detector (NPD) used as the detection component of a gas chromatographic system.1.2 This practice applies to an NPD that employs a heated alkali metal compound and emits an electrical charge from that solid surface.1.3 This practice addresses the operation and performance of the NPD independently of the chromatographic column. However, the performance is specified in terms that the analyst can use to predict overall system performance when the detector is coupled to the column and other chromatographic components.1.4 For general chromatographic procedures, Practice E260 should be followed except where specific changes are recommended in this practice for the use of a nitrogen/phosphorus (N/P) thermionic detector.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific safety information, see Section 5, Hazards.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice provides a method for the in-road installation of an inductive loop detector that consists of wire loops, lead-in wires, and lead-in cable. The practice is intended for installing wires in saw cuts made in the roadway surface and not for installing preformed loops that may be encased in a protective enclosure such as plastic conduit. Typical components of an inductive loop detector system are illustrated in Fig. 1. Modern inductive loop detector electronic units are capable of detecting vehicles even if the wire loop is laid on reinforcing steel before concrete is placed.FIG. 1 Inductive Loop Detector System (Notional) (2)1.1 This practice describes the recommended procedure for installing inductive loop detectors in sawed slots in roadway pavement for use as a traffic monitoring device or to actuate traffic control devices such as a traffic signal. Although the practice is not intended for installing preformed loops, the practice does contain information of value for this type of loop, such as recommendations for the number of turns of loop wire, number and direction of twists in the lead-in wire and cable, splice location (if needed), and grounding options.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice is intended to describe the performance of a conductivity detector independent of the chromatographic system in terms that the analyst can use to predict overall system performance when the detector is coupled to the column and other chromatography system components.5.2 Although it is possible to observe each of the several characteristics of a detector under different and unique conditions, it is the intent of this practice that a complete set of detector specifications should be obtained at the same operating conditions, including the setup used for testing, flow rates, and temperatures. It should be noted that to specify a detector's capability completely, its performance should be measured at several sets of conditions within the useful range of the detector. The terms and tests described in this practice are sufficiently general so that they may be used at whatever conditions may be chosen for other reasons.1.1 This practice covers the testing of the performance of conductivity detectors used as the detection component of a liquid or ion chromatography system.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This standard applies to all walk-through metal detectors that are used to find metal contraband concealed or hidden on people.1.2 This standard describes baseline acceptable technical performance requirements, which includes metal object detection performance, safety (electrical, mechanical, fire), electromagnetic compatibility, environmental conditions and ranges, and mechanical durability. The requirements for metal detection performance are unique and, therefore, test methods for these parameters are provided, including the design of test objects. An agency or organization using this standard is encouraged to add their unique operationally-based requirements to those requirements listed in this baseline technical performance standard.NOTE 1: For ease of use, steps of test procedures in this standard are indicated by numbered lists.1.3 This standard describes the use of threat object exemplars, instead of actual threat objects, to test the detection performance of walk-through metal detectors.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 This terminology was drafted to exclude any commercial relevance to any one vendor by using only general terms that are acknowledged by all vendors and should be revised as charge-coupled device (CCD) technology matures. This terminology uses standard explanations, symbols, and abbreviations.1.1 This terminology brings together and clarifies the basic terms and definitions used with scientific grade cooled charge-coupled device (CCD) detectors, thus allowing end users and vendors to use common documented terminology when evaluating or discussing these instruments. CCD detectors are sensitive to light in the region from 200 nm to 1100 nm and the terminology outlined in the document is based on the detection technology developed around CCDs for this range of the spectrum.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The significant attributes of this practice are the methods for determining the detection capabilities of metal detectors, the methods for determining the effects of outside influences on detectors, and certain safety requirements for detectors.4.2 While this practice was originated for walk-through metal weapons detectors, it is equally applicable to detectors of other metal objects. The innocent objects set (15.1.2) would require modification commensurate with the size of the other object to be tested; some tests may not be applicable and other specific and different tests may be necessary.4.3 This practice includes testing site requirements (Section 6) to minimize data variations. These methods may be used at nonconforming sites if site-related disturbances are considered and accounted for.4.4 This practice is not meant to constrain designs but it is applicable only to detectors which are designed for individual walk-through. The portal structure shall be deemed to meet this criterion if it provides a minimum vertical clearance of 1.96 m (77 in.) and a minimum horizontal width clearance of 0.66 m (26 in.).4.5 This practice recognizes that the complex movements of a test object when carried by a person walking through a detector limits the precision and repeatability of the resultant observed signals. Averaged results from repeated tests under identical controlled conditions are recommended to obtain a better approximation of the underlying hypothetical true value for that set of conditions.4.6 Where the term “significant” is used, it refers to phenomena which, in accordance with accepted engineering practices, exceed the normal variation of data.1.1 This practice covers methods for the evaluation of walk-through metal weapons detectors and criteria for testing metal detection performance.1.2 This practice specifies certain health, safety, and human factors criteria pertaining to the usage of the detection equipment.1.3 This practice requires the use of non-standardized (user-supplied) test objects and test equipment. Evaluations made using the procedures outlined in this practice can be used for comparative evaluations only if the tests are made with the same equipment and test objects.1.4 This practice is intended for use by manufacturers and evaluators of electromagnetic field devices used for screening persons entering into controlled access areas. It is not intended to set performance nor limit or constrain operating technologies, nor is it a document for use by individual operators or users of such equipment at specific access control points.1.5 The values stated in SI units are to be regarded as the standard. Other units given in parentheses are for information only.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For a specific hazards statement, see warning note in 12.2.5.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This practice is intended as a guide for the use of a flame photometric detector (FPD) as the detection component of a gas chromatographic system. The different principles of flame photometric detectors, and detector construction are presented in details. The detector sensitivity, minimum detectability, dynamic range, power law of sulphur response, linear range-phosphorus mode, unipower response range, noise and drift, and specificity are presented in details. The photomultiplier dark current is the magnitude of the FPD output signal measured with the FPD flame off. Flame background current is the difference in FPD output signal with the flame on and with the flame off in the absence of phosphorus or sulfur compounds in the flame.1.1 This practice is intended as a guide for the use of a flame photometric detector (FPD) as the detection component of a gas chromatographic system.1.2 This practice is directly applicable to an FPD that employs a hydrogen-air flame burner, an optical filter for selective spectral viewing of light emitted by the flame, and a photomultiplier tube for measuring the intensity of light emitted.1.3 This practice describes the most frequent use of the FPD which is as an element-specific detector for compounds containing sulfur (S) or phosphorus (P) atoms. However, nomenclature described in this practice are also applicable to uses of the FPD other than sulfur or phosphorus specific detection.1.4 This practice is intended to describe the operation and performance of the FPD itself independently of the chromatographic column. However, the performance of the detector is described in terms which the analyst can use to predict overall system performance when the detector is coupled to the column and other chromatographic system components.1.5 For general gas chromatographic procedures, Practice E260 should be followed except where specific changes are recommended herein for use of an FPD.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific safety information, see Section 4, Hazards.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 Although it is possible to observe and measure each of the several characteristics of a detector under different and unique conditions, it is the intent of this practice that a complete set of detector specifications should be obtained at the same operating conditions. It should be noted also that to specify a detector’s capability completely, its performance should be measured at several sets of conditions within the useful range of the detector. The terms and tests described in this practice are sufficiently general so that they may be used at whatever conditions may be chosen for other reasons.3.2 Linearity and speed of response of the recorder used should be such that it does not distort or otherwise interfere with the performance of the detector. Effective recorder response, Refs. (5, 6) in particular, should be sufficiently fast that it can be neglected in sensitivity of measurements. If additional amplifiers are used between the detector and the final readout device, their characteristics should also first be established.1.1 This practice is intended to serve as a guide for the testing of the performance of a thermal conductivity detector (TCD) used as the detection component of a gas chromatographic system.1.2 This practice is directly applicable to thermal conductivity detectors which employ filament (hot wire) or thermistor sensing elements.1.3 This practice is intended to describe the performance of the detector itself independently of the chromatographic column, in terms which the analyst can use to predict overall system performance when the detector is coupled to the column and other chromatography system components.1.4 For general gas chromatographic procedures, Practice E260 should be followed except where specific changes are recommended herein for the use of a TCD. For definitions of gas chromatography and its various terms see Practice E355.1.5 For general information concerning the principles, construction, and operation of TCD see Refs. (1-4).21.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific safety information, see Section 4.31.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This practice describes the photomultiplier properties that are essential to their judicious selection and use of in emission and absorption spectrometry. The properties covered here include structural features, electrical properties, and characteristics involved in precautions and problems. The structural features covered are envelope configurations, window materials, electrical connections, and housing for the external structure, and the photocathode, dynodes and anode, and rigidness of structural components for the internal structure. Electrical properties, on the other hand, incorporate the following: optical-electronic characteristics of the photocathode including spectral response; current amplification including gain per stage, overall gain, gain control (voltage-divider bridge), linearity of response, and anode saturation; signal nature; dark current including cathode size, internal aperture, and refrigeration effects; noise nature including additivity of noise power, signal-to-noise ratio, equivalent noise input; and photomultiplier properties as a component in an electrical circuit including output impedance, response time, and signal gating and integration possibilities. Finally, the characteristics involved in precautions and problems cover fatigue and hysteresis effects, illumination of photocathode, and gas leakage.1.1 This practice covers photomultiplier properties that are essential to their judicious selection and use in emission and absorption spectrometry. Descriptions of these properties can be found in the following sections:  SectionStructural Features 4 General 4.1 External Structure 4.2 Internal Structure 4.3Electrical Properties 5 General 5.1 Optical-Electronic Characteristics of the Photocathode 5.2 Current Amplification 5.3 Signal Nature 5.4 Dark Current 5.5 Noise Nature 5.6 Photomultiplier as a Component in an Electrical Circuit 5.7Precautions and Problems 6 General 6.1 Fatigue and Hysteresis Effects 6.2 Illumination of Photocathode 6.3 Gas Leakage 6.4Recommendations on Important Selection Criteria 71.2 Radiation in the frequency range common to analytical emission and absorption spectrometry is detected by photomultipliers presently to the exclusion of most other transducers. Detection limits, analytical sensitivity, and accuracy depend on the characteristics of these current-amplifying detectors as well as other factors in the system.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Commercial trace detectors are used by first responders, security screeners, the military, and law enforcement to detect and identify explosive threats and drugs of interest quickly. These trace detectors typically operate by detecting chemical agents in residues and particles sampled from surfaces and can have detection limits for some compounds extending below 1 ng. A trace detector is set to alarm when its response to any target analyte exceeds a programmed threshold level for that analyte. Factory settings of such levels typically balance sensitivity and selectivity assuming standard operating and deployment conditions.5.2 The LOD for a substance is commonly accepted as the smallest amount of that substance that can be reliably detected in a given type of medium by a specific measurement process (2). The analytical signal from this amount shall be high enough above ambient background variation to give statistical confidence that the signal is real. Methods for determining nominal LOD values are well known but pitfalls exist in specific applications. Vendors of trace detectors often report detection limits for only a single compound without defining the meaning of terms or reference to the method of determination.NOTE 2: There are several different “detection limits” that can be determined for analytical procedures. These include the minimum detectable value, the instrument detection limit, the method detection limit, the limit of recognition, the limit of quantitation, and the minimum consistently detectable amount. Even when the same terminology is used, there can be differences in the LOD according to nuances in the definition used, the assumed response model, and the type of noise contributing to the measurement.5.3 When deployed, the individual performance of a trace detector (for example, realistic LODs) is influenced by: (1) manufacturing differences, history, and maintenance; (2) operating configurations (for example, thermal desorption temperature, analyzer temperature, and type of swab); and (3) environmental conditions (for example, ambient humidity and temperature and chemical background). As a result, realistic LOD values for a trace detector may be poorly estimated by the factory specifications. These fundamental measures of performance are critically important for assessing the ability of an instrument to detect trace levels of particular compounds in a particular setting, so a reliable and accessible method is needed to estimate realistic LOD values, especially in the field.5.4 Technical Challenges and Pitfalls to the Estimation of LOD Values in Trace Detectors and the Setting of Optimal Alarm Thresholds: 5.4.1 —The U.S. Department of Justice lists over 230 explosive materials and over 270 controlled drugs having a high potential for abuse.4 There are many technologies used for trace detection, and instrument manufacturers design their systems and balance operating conditions to provide detection capabilities across as many analytes as possible. However, a very limited subset of analytes is normally used to test and verify detector performance. Therefore, default operating conditions and alarm thresholds may not be optimally set to detect reliably certain compounds deemed important in particular scenarios.5.4.2 Environment—Ambient conditions and chemical background vary with the deployment location, which would influence response sensitivities and LOD values.5.4.3 Risk Tolerance and Balance—Values of alpha risk (false positive probability of process blanks) and beta risk (false nondetection probability of analytes at the detection limit) should be balanced and set according to security priorities (for example, alert level, probable threat compounds, throughput requirements, human factors, and risk tolerance). The default risk balance in a trace detector may not be adequate for the deployment situation.5.4.4 Signal Variability (Heteroskedasticity)—The variance in instrument response may not be consistent across analyte mass levels introduced into the trace detector. In ion mobility spectrometry (IMS)-based technologies, the physicochemical mechanisms underlying atmospheric pressure ionization (with a finite number of available reactant ions) and ion mobility separation may be non-uniform across the response regions. Typical methods of LOD estimation usually assume constant variance.5.4.5 Proprietary Signal Processing—Typical LOD determinations assume Gaussian distributions and use background variation as an important parameter. Unfortunately, alarm decisions in trace detectors are rarely based on raw measurement signals; rather, proprietary algorithms are used to process the raw measurements. This processing may attempt to minimize alpha risk by truncating or dampening background signals, so background signals may be absent or the true distribution in these processed signals may be non-Gaussian, confounding the calculation of an accurate LOD.5.4.6 Multivariate Considerations—To improve selectivity and decrease alpha risk, alarm decisions in trace detectors may be based on multiple-peak responses rather than a single-peak amplitude measurement. Efforts to recognize and quantify unique ion fragmentation patterns across both the thermal desorption and drift-time domains are being developed for next-generation detectors.5.4.7 Diversity of Technologies—The wide variety of trace detectors and technologies on the market and those under development challenge general response models for accurate estimation of LOD.5.4.8 Security—LOD values for explosives in trace detectors may not be openly published because of security and classification issues.1.1 In harmony with the Joint Committee for Guides in Metrology (JCGM) and detection concepts of the International Union of Pure and Applied Chemistry (IUPAC) (1, 2)2, this test method uses a series of replicated measurements of an analyte at dosage levels giving instrumental responses that bracket the critical value, a truncated normal distribution model, and confidence bounds to establish a standard for estimating practical and statistically robust limits of detection.NOTE 1: Other standards are available that evaluate the general performance of detection technologies for various analytes in complex matrices (for example, Practice E2520).1.2 Here, the limit of detection (LOD90) for a compound is defined to be the lowest mass of that compound deposited on a sampling swab for which there is 90 % confidence that a single measurement in a particular trace detector will have a true detection probability of at least 90 % and a true nondetection probability of at least 90 % when measuring a process blank sample.1.3 This particular test method was chosen on the basis of reliability, practicability, and comprehensiveness across tested trace detectors, analytes, and deployment conditions. The calculations involved in this test method are published elsewhere (3), and are performed through an interactive web-based calculator available on the National Institute of Standards and Technology (NIST) site: https://www-s.nist.gov/loda.1.4 Intended Users—Trace detector developers and manufacturers, vendors, testing laboratories, and agencies responsible for public safety and enabling effective deterrents to terrorism.1.5 While this test method may be applied to any detection technology that produces numerical output, the method is especially applicable to measurement systems influenced by heterogeneous error sources that lead to non-linear and heteroskedastic dose/response relationships and truncated or censored response distributions at low analyte levels. The procedures have been tested using explosive and drug compounds in trace detectors based on ion mobility spectrometry, gas chromatography, and mass spectrometry (4). Compounds are deposited as liquid solutions on swabs and dried before use. Background interferences introduced to the test samples were representative of a variety of conditions expected during deployment, but these conditions were not intended as comprehensive in representing all possible scenarios. The user should be aware of the possibility that untested scenarios may lead to failure in the estimation of a reliable LOD90 value.1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Some specific hazards statements are given in Section 8 on Hazards.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification establishes the baseline performance requirements and additional optional capabilities for stationary point chemical vapor detectors (SPCVD) intended for continuous monitoring of public, non-industrial facilities 24 hours a day, 7 days a week. It provides SPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs. The document specifies chemical detection performance requirements, system requirements, environmental requirements, manuals and documentation, and product marking.1.1 General:1.1.1 This specification presents baseline performance requirements and additional optional capabilities for stationary point chemical vapor detectors (SPCVD) designed for continuous, 24 h a day 7 days a week, monitoring of public, non-industrial facilities. This specification is one of several that describe chemical vapor detectors (for example, handheld and stationary) and chemical detection capabilities including: chemical vapor hazard detection, identification, classification, and quantification. An SPCVD is capable of detecting and alarming when exposed to chemical vapors that pose a risk as defined by the Acute Exposure Guideline Levels for Selected Airborne Chemicals (AEGL). For example, chemical vapors of interest for homeland security applications, see Appendix X1. The SPCVD should not alarm to background chemical vapors and should provide low false positive alarm rates and no false negatives. Procurement agents and end users must identify the specific chemicals of interest and environmental requirements for the given facility.1.1.1.1 An SPCVD samples air from immediate surroundings and is comprised of one or more detectors using one or more chemical detection technologies. An SPCVD also includes air sampling system(s), power system(s), computer(s), data storage, data network communication interface(s), and an enclosure, see Fig. 1. An SPCVD may be combined with other SPCVDs, other chemical, biological, radiological, nuclear, and explosive (CBRNE) detectors, and other monitoring devices such as video. A remote command center may monitor and control these devices and communicate information to the responsible authorities and responders, as depicted in Fig. 2.FIG. 1 An Example Schematic of a Stationary Point Chemical Vapor Detector (SPCVD)The SPCVD is a unit which samples air from immediate surroundings and is comprised of one or more detectors using one or more chemical detection technologies. An SPCVD also includes air sampling system(s), power system(s), computer(s), data storage, data network communication interface(s), and an enclosure.FIG. 2 A Conceptual Representation of a Facility Security System with Stationary Point Chemical Vapor Detectors (SPCVDs) integrated with other Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) Detectors, and Other Monitoring Devices such as Video1.1.2 This specification provides the SPCVD baseline requirements, including performance, system, environmental, and documentation requirements. This specification provides SPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs.1.1.3 This specification is not meant to provide for all uses. Manufacturers, purchasers, and end users will need to determine specific requirements based on the installation location and environment.1.2 SPCVD Chemical Detection Capabilities—Manufacturers document and verify, through testing, the chemical detection capabilities of the SPCVD. Test methods for assessing chemical detection capabilities are available from the Department of Homeland Security and the Department of Defense and are listed in Appendix X2.1.3 SPCVD System and Environmental Properties—Manufacturers document and verify, through testing, the system and environmental properties of the SPCVD. Example test methods for assessing the system and environmental properties are listed in Appendix X3.1.4 Units—The values stated in SI units are to be regarded as standard. Vapor concentrations of the hazardous materials are presented in parts per million (ppm) as used in Acute Exposure Guideline Levels for Selected Airborne Chemicals, Vols 1-9 (see 2.2) and in mg/m3.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This guide provides information on testing systems and their components used for measuring responses of CO alarms or detectors subjected to gases, vapors, and their mixtures. Components of a testing system include a chamber, clean air supply module, humidification module, gas and vapor delivery module, and verification and control instrumentation.5.2 The CO detector is tested by sequential exposure to CO and interference gases at the specified challenge concentrations. A properly functioning alarm/detector will sound upon sufficient exposure to CO but will not sound upon any exposure to interference gases consistent with applicable standards (for example, IAS 6-96 (1),5 L 2034).1.1 This guide describes testing systems used for measuring responses of carbon monoxide (CO) alarms or detectors subjected to gases, vapors, and their mixtures.1.2 The systems are used to evaluate responses of CO detectors to various CO concentrations, to verify that the detectors alarm at certain specified CO concentrations, and to verify that CO detectors do not alarm at certain other specified CO concentrations.1.3 The systems are used for evaluating CO detector responses to gases and vapors that may interfere with the ability of detectors to respond to CO.1.4 Major components of such a testing system include a chamber, clean air supply module, humidification module, gas and vapor delivery module, and verification and control instrumentation.1.5 For each component, this guide provides a comparison of different approaches and discusses their advantages and disadvantages.1.6 The guide also presents recommendations for a minimum configuration of a testing system.1.7 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For more specific safety precautionary information, see 6.2.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification establishes baseline performance requirements and additional optional capabilities for handheld point chemical vapor detectors (HPCVD) intended for homeland security applications. It provides HPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs. The document specifies chemical detection performance requirements, system requirements, environmental requirements, manuals and documentation, product marking, and packaging.1.1 General: 1.1.1 This document presents baseline performance requirements and additional optional capabilities for handheld point chemical vapor detectors (HPCVD) for homeland security applications. This document is one of several that describe chemical vapor detectors (for example, handheld and stationary) and chemical detection capabilities including: chemical vapor hazard detection, identification, and quantification. An HPCVD is capable of detecting and alarming when exposed to chemical vapors that pose a risk as defined by the Acute Exposure Guideline Levels for Selected Airborne Chemicals (AEGL).1.1.2 This document provides the HPCVD baseline requirements, including performance, system, environmental, and documentation requirements. This document provides HPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs.1.1.3 This document is not meant to provide for all uses. Manufacturers, purchasers, and end users will need to determine specific requirements including, but not limited to, use by HAZMAT teams, use in explosive atmospheres, use with personal protective equipment (PPE), use by firefighters and law enforcement officers, special electromagnetic compatibility needs, extended storage periods, and extended mission time. These specific requirements may or may not be generally applicable to all HPCVDs.1.2 Operational Concepts—HPCVDs are used to detect, identify, classify, or quantify, or combinations thereof, chemical vapor hazards that pose 30-min Acute Exposure Guideline Level-2 (AEGL-2) dangers. The HPCVD should not alarm to environmental background chemical vapors and should provide low false positive alarm rates and no false negatives. Uses of an HPCVD include search and rescue, survey, surveillance, sampling, and temporary fixed-site monitoring. An HPCVD should withstand the rigors associated with uses including, but not limited to, high- and low-temperature use and storage conditions; shock and vibration; radio frequency interference; and rapid changes in operating temperature, pressure, and humidity.1.3 HPCVD Chemical Detection Capabilities—Manufacturers document and verify, through testing, the chemical detection capabilities of the HPCVD. Test methods for assessing chemical detection capabilities are available from the Department of Homeland Security and the Department of Defense and are listed in Appendix X3.1.4 HPCVD System and Environmental Properties—Manufacturers document and verify, through testing, the system and environmental properties of the HPCVD. Example test methods for assessing the system and environmental properties are listed in Appendix X4.1.5 Units—The values stated in SI units are to be regarded as the standard. Vapor concentrations of the hazardous materials are presented in parts per million (ppm) as used in Acute Exposure Guideline Levels for Selected Airborne Chemicals, Vols 1-9 (see 2.1) and in mg/m3.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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