1、Designation:D653000(Reapproved 2013)Standard Test Method forTotal Active Biomass in Cooling Tower Waters(Kool KountAssay;KKA)1This standard is issued under the fixed designation D6530;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,t
2、he year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of viableactive biomass in cooling tower water in the range from 102to
3、108cfu/mL(1).It is a semiquantitative test method.1.2 This test method was used successfully with reagentwater,physiologic saline,and cooling tower waters.It is theusers responsibility to ensure the validity of this test methodfor waters of untested matrices.1.3 This standard does not purport to add
4、ress 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 and determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see Section 9.2.Referenced Do
5、cuments2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1192 Guide for Equipment for Sampling Water and Steamin Closed Conduits(Withdrawn 2003)3D1193 Specification for Reagent WaterD3370 Practices for Sampling Water from Closed Conduits3.Terminology3.1 DefinitionsFor definitions of terms used
6、 in this testmethod,refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 snapping cupcontainer provided for holding thesample and snapping tip of the vial.3.2.2 vialsealed glass ampoule under vacuum containingreagents for the Kool Kount Test.3.3 Symbols:3.3.1 cfu/mLcol
7、ony forming units per millilitre.4.Summary of Test Method4.1 This test method consists of adding a specific volume ofwater to nutrients and a color indicator contained in a glassvial.The contents of the vial are then mixed and incubated at95F(35 6 3C;that is,in a shirt pocket,incubator,or heatblock)
8、.The color of the sample after addition into the vialcontaining the nutrients and color indicator is yellow.Viableactive biomass in the sample replicates using the nutrientsprovided and reduces the color indicator.At a critical biomassconcentration,sufficient quantities of the color indicator arered
9、uced resulting in a visible change in the indicator from theoriginal yellow sample color to orange.The time required forconversion of the oxidized indicator to the reduced indicatorresulting in an orange color as directly correlated with theconcentration of viable active biomass in the water samplet
10、ested.High concentrations of active biomass in the sampleproduce the positive orange color more rapidly than lowconcentrations of viable biomass.5.Significance and Use5.1 This test method is useful for rapid determination ofviable active biomass concentrations in cooling tower waters.The efficiency
11、of cooling towers is directly affected by theconcentration of biomass in the cooling tower waters.Asbiomass concentrations increase,biofilm formation occursresulting in a decrease in the efficiency of heat exchange in thetower.Current tests for monitoring the biomass concentrationin cooling towers r
12、equire at least 36 h for growth of themicroorganisms on a solid agar surface for counting.Replica-tion of microorganisms over the 36-h period before results areavailable creates an aqueous environment which is no longerrepresented by the data generated.Timely test results can assistin minimizing bio
13、cide addition to control biomass concentra-tions.Kool Kount provides data within hours to allow for moreprecise control of active biomass concentrations in the waters.6.Interferences6.1 Halogens interfere with this test method by inhibitingmicrobial growth resulting in lengthy incubation periods bef
14、ore1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.24 on Water Microbiology.Current edition approved June 1,2013.Published July 2013.Originally approvedin 2000.Last previous edition approved in 2006 as D6530 00(2006).DOI:
15、10.1520/D6530-00R13.2For referenced ASTM standards,visit 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.3The last approved version of this historical
16、standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 a positive orange color is produced suggesting better waterquality.Addition of thiosulfate eliminates this interference andallows for testing of waters previously treated with halogens(not immediately prior to testing).6.2 Reducing agents(that is,beta mercaptoethanol)mayinterfere in this test method by reducing the color indicatorchemically.Rapid col