ASTM_G_140_-_02_2014.pdf

Designation:G14002(Reapproved 2014)Standard Test Method forDetermining Atmospheric Chloride Deposition Rate by WetCandle Method1This standard is issued under the fixed designation G140;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the 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 a wet candle device and its usein measuring atmospheric chloride deposition(amount ofchloride salts deposited from the atmosphere on a given areaper unit time).1.2 Data on atmospheric chloride deposition can be usefulin classifying the corrosivity of a specific area,such as anatmospheric test site.Caution must be exercised,however,totake into consideration the season because airborne chloridesvary widely between seasons.1.3 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 and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD4458 Test Method for Chloride Ions in Brackish Water,Seawater,and BrinesG92 Practice for Characterization of Atmospheric Test Sites2.2 ISO Standard:ISO 9225 Corrosion of Metals and Alloys.Aggressivity ofAtmospheresMethods of Measurement of PollutionData33.Significance and Use3.1 This test method is capable of generating quantitativevalues of atmospheric chloride deposition specifying milli-grams of chloride ions per square metre per day(or other unitsderived from such values).NOTE1Chlorides in the atmosphere exist as a suspension of liquiddroplets or solid particles.They are transported to solid surfaces bygravity,wind,or brownian motions.These transport mechanisms aredirection-sensitive so that a vertical cylinder will not necessarily receivethe same flux as a horizontal plate,or objects with different sizes andorientations.Therefore,the use of this approach to provide an indicationof the deposition of chlorides on objects in atmospheric exposures may notbe quantitatively accurate;however,this technique has been successful inclassifying the severity of exposure in a variety of marine locations.3.2 The sites where samples are to be taken and thesampling time periods should be established.A continuousprogram of monthly or 30-day exposures is recommended forsite characterization.Seasonal monitoring may be performed ifthere are specific periods of interest.4.Apparatus4.1 ComponentsThe components needed to construct onewet candle device are as follows:4.1.1 Erlenmeyer Flask,narrow mouth,500 mL,(glass orpolypropylene).Other size flasks may be used,but dimensionsin Fig.1 will have to be adjusted accordingly.NOTE2Polypropylene flasks are recommended during threat offreezing weather.4.1.2 Glass Test Tube,general purpose,16 by 150-mmlength.4.1.3 Solid Rubber or Neoprene Stopper,No.7,diameter top38 mm,bottom 30 mm.4.1.4 Cotton Bandage Gauze,strip,50 mm wide and ap-proximately 1500 mm long.NOTE3The overall length of the gauze may vary with installation.4.1.5 Type IV Reagent Water,1 L,200 mL CHOH(CH2OH2)(glycerin)and 20 drops CH3(CH2)6COOH(oc-tanoic acid)should be added to prevent freezing,if necessary(See Specification D1193).4.1.6 Gloves,vinyl,one pair.NOTE4Poly(vinyl chloride)(PVC)is recommended.Latex gloves arenot acceptable,as their chloride content is reported to be comparable tothat of human hands.4.2 Support StandAsuitable support stand shall be erectedat the site where the atmosphere is to be sampled.A treated1This test method is under the jurisdiction of ASTM Committee G01 onCorrosion of Metals and is the direct responsibility of Subcommittee G01.04 onAtmospheric Corrosion.Current edition approved Nov.1,2014.Published November 2014.Originallyapproved in 1996.Last previous edition approved in 2008 as G14002(2008).DOI:10.1520/G0140-02R14.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 wood post(100 by 100 by 2250 mm)or galvanized pipe(42-mm diameter by 2250-mm length)with an attached plateon top is suitable,with 750 mm in the ground and 1500 mmabove the ground on which the apparatus to hold the candle canbe mounted(see Fig.1).The apparatus shall be mounted sothat the arms supporting the rain cover do not shield the gauzefrom a known source of chloride.4.3 Assembly of the Wet Candle Apparatus(see Fig.1):4.3.1 The rubber stopper m