【国外标准】 Standard Practices for Preparation and Preliminary Testing of Water-Formed Deposits

4.1 Deposits in piping from aqueous process streams serve as an indicator of fouling, corrosion or scaling. Rapid techniques of analysis are useful in identifying the nature of the deposit so that the reason for deposition can be ascertained.4.2 Possible treatment schemes can be devised to prevent deposition from reoccurring.4.3 Deposits formed from or by water in all its phases may be further classified as scale, sludge, corrosion products or biological deposits. The overall composition of a deposit or some part of a deposit may be determined by chemical or spectrographic analysis; the constituents actually present as chemical substances may be identified by microscope or X-ray.1.1 These practices provide directions for the preparation of the sample for analysis, the preliminary examination of the sample, and methods for dissolving the analytical sample or selectively separating constituents of concern.1.2 The general practices given here can be applied to analysis of samples from a variety of surfaces that are subject to water-formed deposits. However, the investigator must resort to individual experience and judgement in applying these procedures to specific problems.1.3 The practices include the following:  SectionsPreparation of the Analytical Sample  8Preliminary Testing of the Analytical Sample  9Dissolving the Analytical Sample 101.4 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.For a specific warning statement, see Note 2.1.6 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.