定价： 571元 加购物车

定价： 590元 加购物车

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定价： 515元 加购物车

定价： 590元 加购物车

定价： 646元 加购物车

定价： 571元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

定价： 515元 加购物车

定价： 646元 加购物车

定价： 571元 加购物车

5.1 The incidental conversion of organic material to trihalomethanes and other volatile organohalides during chlorination of water is a possible health hazard and is the object of much research. This test method can be used as a rapid, simple means for determining many volatile organohalides in raw and processed water.1.1 This test method covers the analysis of drinking water. It is also applicable to many environmental and waste waters when adequate validation is included.1.2 This test method covers the determination of halomethanes, haloethanes, and some related extractable organohalides amenable to gas chromatographic measurement. The applicable concentration range for trihalomethanes is from 1 to 200 μg/L. Detection limits depend on the compound, matrix, and on the characteristics of the gas chromatographic system.1.3 For compounds not specifically included in the precision and bias section the analyst should validate the test method by collecting precision and bias data on actual samples.1.4 Confirmation of component identities is obtained by observing retention times using gas chromatographic columns of different polarities. When concentrations are sufficiently high (>50 μg/L) confirmation with halogen specific detectors or gas chromatography/mass spectrometry (GC/MS) may be used. Confirmation of purgeable compounds at levels down to 1 μg/L can be obtained using Test Method D3871 with GC/MS detection.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. Specific precautionary statements are given in Section 8.1.7 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 guide describes a method of determining the buoyancy to weight ratio of spill response booms. The principle is based on Archimedes Law, which states that a body either wholly or partially immersed in a fluid will experience an upward force equal and opposite to the weight of the fluid displaced by it.4.2 Unless otherwise specified, when used in this guide, the term buoyancy to weight ratio (B/W ratio) refers to the gross buoyancy to weight ratio. Buoyancy is an indicator of a spill response boom’s ability to follow the water surface when exposed to current forces, fouling due to microbial growth (which adds weight), and wave conditions. Surface conditions other than quiescent will have an adverse effect on collection or containment performance. When waves are present, conformance to the surface is essential to prevent losses. Minimum buoyancy to weight ratios for oil spill containment booms are specified in Guide F1523 for various environmental conditions.4.3 This guide provides the methodology necessary to determine the buoyancy to weight ratio using a fluid displacement method. This method is typically applied to booms having relatively low B/W ratios (in the range of 2:1 to 10:1). Booms with greater buoyancies may also be tested in this manner. It is acceptable to use calculation methods to estimate boom displacement for booms with buoyancies greater than 10:1, where the potential error in doing so would have a less significant effect on performance.4.4 When evaluating the B/W ratio of a spill response boom, consideration must be given to the inherent properties of the boom that may affect the net B/W ratio while in use. These considerations include, but are not limited to, absorption of fluids into flotation materials, membranes that are abraded during normal use, and entry of water into components of the boom.The entry of water into boom components is of particular concern with booms that contain their flotation element within an additional membrane. (This is the case for many booms that use rolled-foam flotation and relatively lightweight material for the boom membrane.) It is also important for booms that have pockets that enclose cable or chain tension members or ballast. When new, the membrane enclosure may contain air that would result in increased buoyancy. In normal use, the membrane material may be easily abraded such that it would no longer contain air, and water would be allowed in at abrasion locations. For such booms, the membrane enclosure shall not be considered as part of the flotation of the boom, and the membrane shall be intentionally punctured to allow water to enter during the test procedure.1.1 This guide describes a practical method for determining the buoyancy to weight (B/W) ratio of oil spill containment booms.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.

定价： 515元 加购物车

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