定价： 571元 加购物车

定价： 515元 加购物车

定价： 590元 加购物车

5.1 Microbiological water testing procedures using membrane filtration are based on the premise that all bacteria within a specific size range will be retained by the membrane filter used. If the membrane filter does not retain these bacteria, false negative results or lowered density estimates may occur that could have serious repercussions due to the presence of unrecognized potential health hazards in the water being tested, especially in drinking water.5.1.1 This procedure as devised will enable the user to test each membrane filter lot number for its ability to retain all bacterial equal to, or larger than, the stated membrane pore size.5.2 Since this membrane is often used to sterilize nonautoclavable liquids, it is essential that the retention characteristics of this membrane are stable.1.1 This test method covers a procedure to test membrane filters for their ability to retain bacteria whose diameter is equal to or slightly larger than the 0.2-µm pore size of the membrane filter.1.2 The procedures described are for the use of user laboratories as differentiated from manufacturers’ laboratories.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, 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.

定价： 515元 加购物车

5.1 Microbiological water testing procedures using membrane filtration are based on the premise that all bacteria within a specific size range will be retained by the membrane filter used. If the membrane filter does not retain these bacteria, false negative results or lowered density estimates may occur that could have serious repercussions due to the presence of unrecognized potential health hazards in the water being tested, especially in drinking water.5.2 This procedure as devised will enable the user to test each membrane filter lot number for its ability to retain all bacteria equal to, or larger than, the stated membrane pore size.1.1 This test method covers a procedure to test membrane filters for their ability to retain bacteria whose diameter is equal to or slightly larger than membrane filters with pore size rated at 0.40 to 0.45 μm.1.2 The procedures described are for the use of user laboratories as differentiated from manufacturers’ laboratories.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, 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.

定价： 515元 加购物车

5.1 This practice provides criteria for products used to measure particulate matter present in a sample of aviation turbine fuel. The objective is to verify that filters, support pads, and field monitors fall within the acceptable ranges that are established by this practice.1.1 This practice determines suitability of products used for measuring particulate contamination in aviation turbine fuel when using Test Methods D5452 and D2276.1.2 There are two major parts of this practice. The first is for evaluation of the cellulose acetate butyrate field monitors that are used in combination with the filters and the filter support pads. The second part is for evaluation of the filter when used with an appropriate cellulose acetate butyrate field monitor.1.3 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.4 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.

定价： 590元 加购物车

5.1 This practice has been developed to simulate the stress encountered by terminal point-of-use filters under a range of real-world use conditions with emphasis on thermal and pressure swings. Two parts, A and B, are intended to account for more frequent, less extreme use conditions and less frequent, more extreme use conditions, respectively. The purpose of pre-stressing the filters before testing by Test Method F838 is to demonstrate the ability of the filters to retain bacteria as determined by Test Method F838 after exposure to a series of temperature and pressure swings representative of those that may be encountered under actual use conditions.5.2 This practice is not intended to account for effects on filter performance attributable to differences in the quality of the water being filtered that may be encountered under actual use conditions.5.3 This practice is not intended to simulate the very extreme stress associated with systemic remedial procedures, such as thermal or chemical shock, sometimes implemented in premise plumbing systems.1.1 This practice covers terminal point-of-use (POU) filters intended for intermittent use on showers, faucets, and other water use end-point devices that deliver hot and cold potable water.1.2 This practice does not cover in-line filters.1.3 Units—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.1.4 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.

定价： 590元 加购物车

定价： 515元 加购物车

定价： 590元 加购物车

5.1 Polycyclic aromatic hydrocarbons (PAH) as defined by this test method are compounds made up of two or more fused aromatic rings.5.2 Several PAH are considered to be probable human carcinogens.5.3 PAH are emitted in the atmosphere primarily through wood or fossil fuel combustion.5.4 Two- and three-ring PAH are typically present in urban air at concentrations ranging from 10 to several hundred nanograms per cubic metre (ng/m3); those with four or more rings are usually found at concentrations of a few ng/m3 or lower.5.5 PAH span a broad spectrum of vapor pressures (for example, from 1.1 × 10–2 kPa for naphthalene to 2 × 10–13 kPa for coronene at 25 °C). Table 1 lists some PAH that are frequently found in ambient air. Those with vapor pressures above about 10–8 kPa will be present in the ambient air substantially distributed between the gas and particulate phases. This test method will permit the collection of both phases. However, particulate-phase PAH will tend to be lost from the particulate filter during sampling due to desorption and volatilization.(A) Many of these compounds sublime.5.5.1 The distribution between phases depends on ambient temperature, humidity, types and concentrations of PAH and particulate matter, and residence time in the air. PAH, especially those having vapor pressures above 10–8 kPa, may vaporize from particulate filters during sampling. Consequently, a back-up vapor trap must be used for efficient sampling.5.6 Separate analyses of the filter and vapor trap will not reflect the original atmospheric phase distributions and should be discouraged.1.1 This test method2 specifies sampling, cleanup, and analysis procedures for the determination of polycyclic aromatic hydrocarbons (PAH) in ambient air.1.2 This test method is designed to collect both gas-phase and particulate-phase PAH and to determine them collectively.1.3 This test method is a high-volume sampling (100 to 250 L/min) method capable of detecting PAH at sub-nanograms per cubic metre (ng/m3) concentrations with sampling volumes up to 350 m3 of air.1.4 This test method has been validated for sampling periods up to 24 h.1.5 Precision and bias under normal conditions can be expected to be ±35 to 50 %.1.6 This test method describes a sampling and analysis procedure for PAH that involves collection from air on a combination fine-particle filter and sorbent trap and subsequent analysis by gas chromatography/mass spectrometry (GC/MS).1.7 The range of this test method is approximately 0.05 to 1000 ng/m3 of air sampled.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.9 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. See also Section 8 for additional safety precautions.1.10 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.

定价： 646元 加购物车

定价： 646元 加购物车

定价： 0元 加购物车

定价： 530元

1.1 Scope 1.1.1 This standard applies to newly produced pilot gas filters, hereinafter referred to as filters (See Part IV, Definitions), constructed entirely of new, unused parts and materials. Compliance of a filter with this standard does not im

定价： 3640元 / 折扣价： 3094 元

This PDF includes GI #2. 1. Scope 1.1 This Standard applies to filters rated up to 125 A intended for suppressing electromagnetic interference in, or with, apparatus and machines that are to be connected to an ac supply with nominal system voltages

定价： 455元 / 折扣价： 387 元