1、Designation: D 6903 07Standard Test Method forDetermination of Organic Biocide Release Rate FromAntifouling Coatings in Substitute Ocean Water1This standard is issued under the fixed designation D 6903; the number immediately following the designation indicates the year oforiginal adoption or, in th
2、e case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the laboratory determination ofthe rate at which organic bioc
3、ide is released from an antifoul-ing coating exposed in substitute ocean water. The test is runentirely in the laboratory under controlled conditions of pH,temperature, salinity, and hydrodynamics. Analytical proce-dures are provided for the determination of the release rate of4,5-dichloro-2-n-octyl
4、isothiazolin-3-one (DCOIT), zinc andcopper pyrithione (ZPT and CuPT), and N-cyclopropyl-N-(1,1-dimethylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine(CDMTD). At predetermined intervals, substitute ocean watersamples are analyzed for leached biocide using a suitableanalytical technique.1.2 In cases
5、 in which the antifouling coating contains bothan organic biocide and a copper-based biocide, the release rateof copper may optionally be concurrently determined accord-ing to the procedure found in Test Method D 6442.1.3 The procedure contains the preparation steps for thedetermination of the relea
6、se rate of biocide in substitute oceanwater from antifouling paints including apparatus, reagents,holding tank conditions, and sampling point details. Theprocedure calls for the accurate determination of organicbiocide concentrations in substitute ocean water at the lowgL-1(parts per billion, ppb) l
7、evel. To detect and correct forreagent impurities and allow a suitable level of analyticalprecision to be achieved, the analytical method to be used forthe determination of the concentration of organic biocide insubstitute ocean water must meet the acceptability criteriagiven in Annex A2. Where Anne
8、x A2 specifies a limit ofquantitation (LOQ), the procedure for determining the LOQ forthe organic biocide in substitute ocean water by the analyticalmethod presented in Annex A3 is to be followed.1.4 Suitable analytical methods that use high-performanceliquid chromatography (HPLC) for determining th
9、e concentra-tion of DCOIT, ZPT and CuPT, and CDMTD in substituteocean water are given in Appendix X1-Appendix X3, respec-tively. Other methods may be used provided that they meet theappropriate criteria given in Annex A2.1.5 When the release rate of a highly photosensitive organicbiocide is being de
10、termined, steps must be taken to protect theapparatus and samples from exposure to natural and artificialvisible light sources. Any such requirement for these steps tobe taken for a particular biocide is indicated in Annex A2.1.6 The practical limits for quantifying biocide release ratesby this meth
11、od are from 4.5 to 500 gcm-2d-1for DCOIT, 0.36to 500 gcm-2d-1for CuPT, 0.36 to 500 gcm-2d-1for ZPT,and 2.7 to 500 gcm-2d-1for CDMTD. These ranges may beextended to 3.8 to 500 gcm-2d-1for DCOIT, 0.16 to 500 gcm-2d-1for CuPT, 0.2 to 500 gcm-2d-1for ZPT, and 2.2 to500 gcm-2d-1for CDMTD if the procedure
12、s described inAppendix X1-Appendix X3 (as appropriate) are followed. Thequantitation of release rates lower than these ranges willrequire the use of analytical methods with lower limits ofquantitation than those specified in Annex A2.1.7 The results of this test method do not reflect environ-mental
13、biocide release rates for antifouling products, and arenot suitable for direct use in the process of generatingenvironmental risk assessments, environmental loading esti-mates, or for establishing release rate limits for regulatorypurposes. See also Section 4.1.8 The values stated in SI units are to
14、 be regarded as thestandard. The values given in parentheses are for informationonly.1.9 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices an
15、d determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD 1141 Practice for the Preparation of Substitute OceanWaterD 1193 Specification for Reagent
16、 Water1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.45 on Marine Coatings.Current edition approved Feb. 1, 2007. Published March 2007.2For referenced ASTM standards, visi
17、t the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
18、59, United States.D 6442 Test Method for Determination of Copper ReleaseRate FromAntifouling Coatings in Substitute Ocean Water2.2 U.S. Federal Standard:340 CFR 136, Appendix B, revision 1.113. Summary of Test Method3.1 The candidate paint system is applied to the cylindricaltest specimens. The coat
19、ed specimens are placed in a tank ofsubstitute ocean water in which the levels of organic biocideand copper (where the coating also contains a biocidal coppercompound) are kept below 100 gL-1by circulating thesubstitute ocean water through a suitable filtration system (see5.1.3). At specified interv
20、als, each specimen is placed in 1500mL of substitute ocean water (see Section 8 for details) androtated at 60 rpm for 1 h (or less, see 8.7 for further explanationand instruction). The rate of biocide release from the paint isdetermined by measuring concentrations of the biocide in thesubstitute oce
21、an water in the individual measuring containers.3.2 Annex A2 provides acceptance criteria for analyticalprocedures for measuring the concentration of specific organicbiocides in substitute ocean water. Suitable methods areprovided in Appendix X1-Appendix X3. Alternative methodsmay be used provided t
22、hat they meet the acceptance criteriagiven in Annex A2.4. Significance and Use4.1 This test method is designed to provide a laboratoryprocedure to quantify and characterize changes in the releaserate of organic biocide from antifouling coatings that occurduring a period of immersion under specified
23、laboratoryconditions of constant temperature, pH, salinity, and hydrody-namics. Quantitative measurement of biocide release rate isnecessary to help in selection of materials, providing qualitycontrol, and understanding the performance mechanism.4.2 Results from this test method establish a pattern
24、ofbiocide release from an antifouling coating over a minimum of45 days exposure under controlled laboratory conditions.Biocide release rates of antifouling paints in-service vary overthe life of the coating system depending on the formulation andon the physical and chemical properties of the environ
25、ment.Factors such as differences in berthing locations, operatingschedules, length of service, condition of paint film surface,temperature, pH, and salinity influence the actual release rateunder environmental conditions. Results obtained using thistest method do not reflect actual biocide release r
26、ates that willoccur in service, but provide comparisons of the release ratecharacteristics of different antifouling formulations in substi-tute ocean water under the prescribed laboratory conditions.4.3 By comparison with published copper and organotinrelease rate data4,5obtained either by direct me
27、asurementsfrom ship hulls or release rate measurements from harborexposed panels, all data indicate that the results of this genericrotating-cylinder test method significantly overestimate therelease rate of biocide when compared to release rates underin-service conditions. For example, published re
28、sults demon-strate that this generic test method produces higher measure-ments of copper and organotin release rates than from direct insitu measurements for the same coating on in-service ship hullsand harbor-exposed panels. The difference between the resultsof this test method and the panel and sh
29、ip studies was up to afactor of about 30 based on copper release rate data for severalcommercial antifouling coatings.4, 6No direct release rate datafrom ship hulls or harbor-exposed panels have been generatedto-date for the biocides covered by this method. However, theexpectation is that the result
30、s of this test method, whencompared with the direct measurements from ship hulls andharbor-exposed panels, could follow the same trend. Realisticestimates of the biocide release from a ships hull underin-service conditions can only be obtained from this testmethod where the difference between the re
31、sults obtained bythis test method and the release rate of an antifouling coatingin service is taken into account.4.4 Where the results of this test method are used in theprocess of generating environmental risk assessments, forenvironmental loading estimates, or for regulatory purposes, itis most st
32、rongly recommended that the relationship betweenlaboratory release rates and actual environment inputs is takeninto account to allow a more accurate approximation of thebiocide release rate from antifouling coatings under real-lifeconditions. This can be accomplished through the applicationof approp
33、riate correction factors.65. Apparatus5.1 Sample GenerationSeeAnnexA2 for guidance on anyparticular materials restriction and handling requirements re-lating to each organic biocide.5.1.1 Release Rate Measuring ContainerA nominal 2-L(12-gal) container made of an inert material, approximately13.5 cm
34、(5.3 in.) in diameter and 19 cm (7.5 in.) high, is fittedwith three rods also made of an inert material, approximately 6mm (nominal14 in.) in diameter to serve as baffles. Rods shallbe evenly spaced on the inside circumference of the containerto prevent swirling of the water with the test cylinder d
35、uringrotation. The rods will be secured to the container walls usingan inert adhesive. The material of construction of the releaserate measuring container and rods for use with any particularbiocide shall be as specified in A2.3. When the release rate ofa photosensitive material is to be determined,
36、 the containershall be protected from light. The requirement to protect therelease rate container from light for any particular organicbiocide is indicated in A2.4.NOTE 1The results of this test method will be adversely affected if thebiocide is strongly adsorbed or absorbed by the release rate meas
37、uringcontainer or the test cylinder, or both. Where the release rates of two ormore different biocides are to be concurrently determined from a single set3Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/ww
38、w.access.gpo.gov.4Valkirs, A. O., Seligman, P. F., Haslbeck, E., and Caso, J. S., Marine Bulletin,Vol. 46 (2003), pp. 763779.5Champ, M. A. and Seligman, P. F., Organotin: Environmental Fate and Effects,Chapter 19 Measurement and Significance of the Release Rate for Tributyltin,(1996) Chapman and Hal
39、l, pp 383403.6Finnie,A.A., Improved Estimates of Environmental Copper Release Rate FromAntifouling Coatings, Biofouling, Vol. 22 (2006), pp 279291.D6903072of measurements, the release rate measuring container, associated rods andthe test cylinders must all be made of a material that is inert to all
40、of thebiocides, otherwise repeat testing (different cylinders and measuringcontainers) for each biocide will be required.5.1.2 Constant Temperature ControlThis control is ameans of maintaining the release rate measuring containers ata temperature of 25 6 1C during the rotation period (see 8.7).5.1.3
41、 Holding TankThis tank is an inert plastic containerof such dimensions so as to permit immersion of four or moretest cylinders and must be equipped with a system to circulatethe seawater continuously in the tank through an activatedcarbon filter and, optionally, an absorbent filter.7If an absor-bent
42、 filter is used, regenerate the ion exchange resin followingthe manufacturers instructions and wash the resin with sub-stitute ocean water before use. The rate of water flow and thesize of the filter shall be selected to maintain the concentrationof each organic biocide below 100 gL-1(100 ppb) and,
43、whenthe coating contains a biocidal copper compound, the concen-tration of copper below 100 gL-1. Flow rates should be set toobtain two to eight turnovers per hour. When the release rate ofa photosensitive material is to be determined, the holding tankshall be protected from light. The requirement t
44、o protectholding tank from light for any particular organic biocide isindicated in A2.4.5.1.4 The size and geometry of the tanks as well as thepositioning of the inflow and outflow ports for the watercirculation system shall be selected to obtain a slow, relativelyuniform flow of substitute ocean wa
45、ter past all test cylinders inthe tank. Maintain the pH of the substitute ocean waterbetween 7.9 and 8.1, the salinity between 33 and 34 parts perthousand (ppt), and the temperature at 25 6 1C (77 6 2F).5.1.5 Test CylindersApproximately 6.4-cm (nominal 212-in.) outside diameter by 17.8-cm (nominal 7
46、-in.) long pipe orequivalent cylindrical shapes made of an inert material andcoated with a 10-cm (3.94-in.) band of antifouling paint aroundthe exterior circumference of the test cylinder to provide 200cm2of paint film that can be immersed and freely rotated in therelease rate measuring container (s
47、ee Note 1 and Note 2).Atopdisk, fitted with a shaft of proper diameter for the rotatingdevice, shall be sealed to the cylinder. Seal the bottom of thetest cylinder so as to form a watertight joint. Alternatively,prefabricated one-piece test cylinders with an integral sealedbottom-end can be used. Do
48、 not coat the lower 1 to 2 cm (0.39to 0.79 in.) of the test cylinder. The test cylinder shall be ofsuch height so that a rotating device can be attached to androtate the cylinder with the upper end of the cylinder above thelevel of the test container immersion liquid to prevent entry ofthe immersion
49、 liquid into the test cylinder (seeAnnexA1). Thematerial of construction of the test cylinder (including thebottom end-disk) for use with any particular biocide shall be asspecified in A2.3. It is advisable to weight the cylinder byfilling with water so that the unit does not have buoyancy.NOTE 2When coating release rates are very high, it may be desirableto use a 5-cm band (100-cm2paint area) to avoid exceeding 200 gL-1oforganic biocide in the measuring containers (see 8.7.1).5.1.6 Test Cylinder Rotating DeviceThe device shall becapable of rotating t
