5.1 Poor indoor air quality has been implicated in significant adverse acute and chronic impacts on occupant health and performance. The ability to assess the components contributing to poor indoor air quality is critical for determining best practices for improving indoor air quality.5.2 Measurement of pollutants in indoor environments using sensors and sensor systems provides information needed to improve indoor air quality through pollutant source control, ventilation, filtration or other treatments.5.3 This method uses a test characterization chamber system equipped with reference monitor(s) to evaluate the response of test sensors or test sensor systems to specific types of particles (for example, salt, polystyrene latex, or dust). To facilitate reproducible results, the test particles used within this method are standardized and have known properties. The user is cautioned that a single particle type is not representative of all particles found indoors. The relative response of test sensors or test sensor systems to a reference monitor can vary by a factor of two for different particle types (for example, primary or secondary, organic or inorganic, outdoor or indoor origin; see 6.11.3 for further discussion). Furthermore, the user is cautioned that the lower limit of particle size detection for optical test sensors and test sensor systems is generally 0.3 μm in diameter; particles below this size are generally undetected and may represent a significant health concern as well.1.1 This test method uses a chamber system to evaluate the performance of stationary PM2.5 sensors (sensors) and particle sensor systems (sensor systems) subjected to various test conditions, including temperature, relative humidity, PM2.5 concentration, and coarse PM interferent concentration.1.1.1 This test method covers sensors and sensor systems that can be continuously powered and continuously operated for the duration of any test described in this method through line power or an internal battery of sufficient output. This test method is not meant to evaluate sensors or sensor systems without these capabilities.1.1.2 This test method evaluates the performance of sensors and sensor systems that allow users to collect data in a systemic manner to assess the capabilities and limitations of these devices.1.1.3 This test method is not meant to evaluate sensors or sensor systems without data storage and recording capabilities.1.1.4 This test method is not intended to evaluate indoor air quality sensors and sensor systems for purposes of regulation of outdoor air, homeland security, law enforcement or forensic activity.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 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 The purpose of this test method is to obtain reliable values for the WVTR of plastic film and sheeting.5.2 WVTR is an important property of packaging materials and can often be directly related to shelf life and packaged product stability.5.3 Data from this test method is suitable as a referee method of testing, provided that the purchaser and seller have agreed on sampling procedures, standardization procedures, test conditions, and acceptance criteria.1.1 This test method covers a procedure for determining the rate of water vapor transmission through flexible barrier materials. The method is applicable to sheets and films up to 3 mm (0.1 in.) in thickness, consisting of single or multilayer synthetic or natural polymers and foils, including coated materials. It provides for the determination of (1) water vapor transmission rate (WVTR), (2) the permeance of the film to water vapor, and (3) for homogeneous materials, water vapor permeability coefficient.NOTE 1: Values for water vapor permeance and water vapor permeability must be used with caution. The inverse relationship of WVTR to thickness and the direct relationship of WVTR to the partial pressure differential of water vapor may not always apply.1.2 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.1.3 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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5.1 This practice establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient air quality measurements. Public and private air monitoring interests have manifested themselves as a driving force for the deployment of air quality sensors and instruments to quantify air pollutant concentrations in communities, around schools, around industrial facilities, and elsewhere. Users of air quality sensors require information on the performance and limitations of these devices so that informed decisions regarding their suitability for various purposes can be determined. This practice describes both laboratory and field tests that provide information on candidate instrument repeatability, sensitivity, linearity, cross-interferences, drift and comparability with more costly instruments typically used by entities such as government agencies. The air quality sensors are first evaluated in a laboratory chamber by comparing their response to a reference instrument and challenging the gas sensors with interferents. The sensors are then deployed outdoors for field testing at two sites with different climates against reference air quality instruments. This practice is intended to be referenced in standards and codes that establish minimum performance quality for sensor-based ambient outdoor air monitoring.5.2 This practice is intended for air quality sensors that measure one or more of the criteria pollutants in ambient air (ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, PM10 and PM2.5) that can be operated in outdoor environments and can log a concentration reading. It is not intended for devices or transducers that require additional enclosures for deployment outdoors or post-processing to convert their output signal into a pollutant concentration reading.5.3 It is anticipated that the main users of this practice will be manufacturers, developers, and distributors of outdoor air quality sensors, air quality agencies, and environmental consultants.1.1 This practice establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient outdoor air quality measurements. It describes both laboratory and field tests that provide information on candidate sensor repeatability, sensitivity, linearity, cross-interferences, drift, and comparability against reference instruments.1.2 This practice does not apply to sensors or instruments that remotely measure atmospheric pollutants using open path, lidar, or imaging technology.1.3 The evaluation procedures contained in this practice are for sensors that alone or in combination measure outdoor criteria pollutants in ambient air: particulate matter (PM2.5 and PM10), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO), or nitrogen dioxide (NO2) at concentrations that are relevant to public health.1.4 Testing is to be performed by a competent entity able to demonstrate that it operates in conformity with internationally accepted test laboratory quality standards such as ISO/IEC 17025.1.5 Units—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 This practice is intended for the application of in-line, full-flow inductive wear debris sensors. According to (1), passing the entire lubrication oil flow for aircraft and aero-derivative gas turbines through a debris-monitoring device is a preferred approach to ensure sufficient detection efficiency.4.2 Periodic sampling and analysis of lubricants have long been used as a means to determine overall machinery health (2). The implementation of smaller oil filter pore sizes for machinery operating at higher rotational speeds and energies has reduced the effectiveness of sampled oil analysis for determining abnormal wear prior to severe damage. In addition, sampled oil analysis for equipment that is remote or otherwise difficult to monitor or access is not practical. For these machinery systems, in-line wear debris sensors can be very useful to provide real-time and near-real-time condition monitoring data.4.3 In-line full-flow inductive debris sensors have demonstrated the capability to detect and quantify both ferromagnetic and non-ferromagnetic metallic wear debris. These sensors record metallic wear debris according to size, count, and type (ferromagnetic or non-ferromagnetic). Sensors are available for a variety of oil pipe sizes. The sensors are designed specifically for the protection of rolling element bearings and gears in critical machine applications. Bearings are key elements in machines since their failure often leads to significant secondary damage that can adversely affect safety, operational availability, or operational/maintenance costs, or a combination thereof.4.4 The main advantage of the sensor is the ability to detect early bearing damage and to quantify the severity of damage and rate of progression of failure towards some predefined bearing surface fatigue damage limiting wear scar. Sensor capabilities are summarized as follows:4.4.1 In-line full flow non-intrusive inductive metal detector with no moving parts.4.4.2 Detects both ferromagnetic and non-ferromagnetic metallic wear debris.4.4.3 Detects 95 % or more of metallic wear debris above some minimum particle size threshold.4.4.4 Counts and sizes wear debris detected.4.5 Fig. 1 presents a widely used diagram (2) to describe the progress of metallic wear debris release from normal to catastrophic failure. It must be pointed out that this figure summarizes metallic wear debris observations from all the different wear modes that can range from polishing, rubbing, abrasion, adhesion, grinding, scoring, pitting, spalling, etc. As mentioned in numerous references (1-11), the predominant failure mode of rolling element bearings is spalling or macro pitting. When a bearing spalls, the contact stresses increase and cause more fatigue cracks to form within the bearing subsurface material. The propagation of existing subsurface cracks and creation of new subsurface cracks causes ongoing deterioration of the material that causes it to become a roughened contact surface as illustrated in Fig. 2. This deterioration process produces large numbers of metallic wear debris with a typical size range from 100 to 1000 microns or greater. Thus, rotating machines, such as gas turbines and transmissions, which contain rolling element bearings and gears made from hard steel tend to produce this kind of large metallic wear debris that eventually leads to failure of the machines.FIG. 1 Wear Debris CharacterizationFIG. 2 Typical Bearing Spall4.6 In-line wear debris monitoring provides a more reliable and timely indication of bearing distress for a number of reasons:4.6.1 Firstly, bearing failures on rotating machines tend to occur as events often without sufficient warning and could be missed by means of only periodic inspections or data sampling observations.4.6.2 Secondly, since it is the larger wear metallic debris that are being detected, there is a lower probability of false indication from the normal rubbing wear that will be associated with smaller particles.4.6.3 Thirdly, build or residual debris from manufacturing or maintenance actions can be differentiated from actual damage debris because the cumulative debris counts recorded due to the former tend to decrease while those due to the latter tend to increase.4.6.4 Fourthly, bearing failure tests have shown that wear debris size distribution is independent of bearing size. (2-5) and (11).1.1 This practice covers the minimum requirements for an in-line, non-intrusive, through-flow oil debris monitoring system that monitors ferromagnetic and non-ferromagnetic metallic wear debris from both industrial aero-derivative and aircraft gas turbine engine bearings. Gas turbine engines are rotating machines fitted with high-speed ball and roller bearings that can be the cause of failure modes with high secondary damage potential. (1)21.2 Metallic wear debris considered in this practice range in size from 120 μm (micron) and greater. Metallic wear debris over 1000 μm are sized as over 1000 μm.1.3 This practice is suitable for use with the following lubricants: polyol esters, phosphate esters, petroleum industrial gear oils and petroleum crankcase oils.1.4 This practice is for metallic wear debris detection, not cleanliness.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided 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.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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Scope: Details test and examination criteria for flammable vapor sensor systems and components for use in gas-burning appliances. This standard applies to a flammable vapor sensor or system capable of operating throughout a temperature range of 32oF (0o

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定价： 1106元