1、Designation: E2798 11Standard Test Method forCharacterization of Performance of Pesticide Spray DriftReduction Adjuvants for Ground Application1This standard is issued under the fixed designation E2798; 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method is used to characterize the performanceof pesticide spray drift reduc
3、tion adjuvants with respect tospray droplet size spectra, volume of fines, and other useparameters under simulated field ground application condi-tions. This test method does not include any procedures toevaluate if pump shear degrades the performance of the spraydrift reduction adjuvant.1.2 The val
4、ues stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.NOTE 1This method uses industry-standard units. The followingconversions to SI units are provided for convenience: 1 mph = 1.61 kph;1 in = 2.54 cm; 1 gal/acre = 9.36 L/hectare.1.3 This te
5、st method 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 Documents
6、2.1 ASTM Standards:2D3825 Test Method for Dynamic Surface Tension by theFast-Bubble TechniqueE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE609 Terminology Relating to PesticidesE799 Practice for Determining Data Criteria
7、and Processingfor Liquid Drop Size AnalysisE1260 Test Method for Determining Liquid Drop SizeCharacteristics in a Spray Using Optical NonimagingLight-Scattering InstrumentsE1519 Terminology Relating to Agricultural Tank MixAdjuvantsE1620 Terminology Relating to Liquid Particles andAtomi-zationE2408
8、Test Method for Relative Extensional Viscosity ofAgricultural Spray Tank Mixes2.2 ASABE Standards:3ASAE S572.1 Spray Nozzle Classification by Droplet Spec-tra, March 20092.3 NFPA Standards:4NFPA 30 Flammable and Combustible Liquids CodeNFPA 33 Standard for Spray Application Using Flammableor Combust
9、ible Materials3. Terminology3.1 Definitions for terms used in this test method can befound in Terminologies E456, E609, E1519, and E1620.4. Summary of Test Method4.1 This test method provides guidelines for the measure-ment of parameters pertaining to the performance of driftreduction adjuvants unde
10、r simulated field ground applicationconditions. The measurements can be made in a wind tunnel orspray chamber. The method describes the preparation, compo-sition, and test/application conditions for droplet size and spraypattern measurements. Exact selection of application condi-tions, such as nozzl
11、e type and tank mix partners, may varyaccording to intended use conditions. This test method has notbeen verified for aerial and orchard airblast pesticide applica-tions.5. Significance and Use5.1 Pesticide regulations for the minimization of drift duringpesticide application often require active in
12、gredient (a.i.)product use under defined droplet size conditions. Sprayperformance with respect to transport and deposition of drop-lets and particles at target surfaces and product efficacy for1This test method is under the jurisdiction of ASTM Committee E35 onPesticides and Alternative Control Age
13、nts and is the direct responsibility ofSubcommittee E35.22 on Pesticide Formulations and Delivery Systems.Current edition approved Jan. 1, 2011. Published February 2011. DOI:10:1520/E279811.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servi
14、ceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Agricultural and Biological Engineers(ASABE), 2950 Niles Rd., St. Joseph, MI 49085, http:/www.asabe.org.4Available from National Fire P
15、rotection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02169-7471, http:/www.nfpa.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.desired applications are also affected by droplet size spectra.The effect of drift reduction
16、adjuvants on droplet size spectrashould be understood in this context. The present test methoddescribes standard tests that can be conducted to investigate theperformance of pesticide spray drift reduction adjuvants undersimulated field use conditions for drift management decisionsin the context of
17、the entire spraying process. The measuredreduction in driftable fines and shift in spray droplet sizedistribution can be used to reduce the buffer zones mandated byregulatory agencies.6. Apparatus6.1 Spray chamber or wind tunnel of known air flowcharacteristics. Droplet size measurements may be made
18、 in aspray chamber or wind tunnel. Where a spray chamber is usedfor simulating ground application of pesticides, make provi-sions to have an air flow with a minimum 7 mph velocity in thedirection of the sprayed fluid. The Spray Drift Task Force(http:/) has found that this minimum airflow will keep t
19、he small drops moving forward and preventthem from swirling back and getting measured multiple times.A diagram of an example test arrangement can be seen in Fig.1 of Test Method E1260, but locate the exhaust vent at thebottom of the spray chamber so the ambient air is moving inthe same direction as
20、the sprayed fluid. Where a wind tunnel isused for simulating ground applications of pesticides, size thewind tunnel working section width to allow the spray to fullyform without constriction. The minimum width for normal usewith a wide range of nozzle and atomizer types will be 1 m.The height shall
21、be sufficient to allow a full traverse (usingeither continuous or chordal measurement sampling) throughthe entire spray cross-section. Usually this will require aminimum height of 1 m.6.2 Droplet size analyzer with calibration verification fortests. The droplet size analyzer selected for the tests s
22、hall beappropriate for the type of measurement being conducted andhave a dynamic size range configuration capable of measuringthe entire droplet size range produced by the sprays underinvestigation. Appropriate techniques include, but are notlimited to, laser diffraction, Phase-Doppler particle size
23、 ana-lyzers and imaging systems. Sympatec5and Malvern6makeinstruments capable of measuring spray droplet size using laserdiffraction analysis. Test Method E1260 outlines the procedurefor determining liquid drop size using these instruments.6.3 Liquid preparation and delivery system, including agi-ta
24、tion mechanism for tank mixes.6.4 Nozzle and spray application system for ground appli-cation platforms.7. Hazards7.1 Safety PrecautionsBefore testing, read the precaution-ary statements on the product label, and the Material SafetyData Sheet, or both. Take proper precautions to prevent skincontact
25、and inhalation of the fines, or the vapors, or both. Takecare to prevent contamination of the surrounding area. Alwayswear the appropriate safety equipment and, where indicated,wear respiratory devices approved by NIOSH for the productbeing tested.7.1.1 WarningA spray of flammable liquid dispersed i
26、nair presents the risk of explosion and fire. Refer to NFPA 30 orNFPA 33 for information about safe practices for storage andhandling of flammable liquids and for spray processes involv-ing sprays of flammable liquids.7.1.2 WarningExposure to drops of various liquids byinhalation, ingestion, and ski
27、n contact may constitute healthhazards.7.1.3 WarningEmission of some sprayed liquids into theatmosphere may be harmful to the environment or may pose ahealth risk.7.1.4 WarningLaser-based instruments contain lasers orother strong light sources which may pose a hazard to personsin their vicinity.7.2
28、Contain all sprayed material and be sure to dispose ofthis material and remaining test substances properly.8. Selection of Test Substances8.1 Select test substances that reflect the intended end-use ofthe drift reduction adjuvant. While water can provide a usefulbaseline for range-finding tests, it
29、must not be the sole systemtested. Use the active ingredient pesticide formulation spraytank mixture as one of the test substances with the adjuvant.For example, commercial herbicides may be selected foradjuvants intended for use in herbicide applications. The userate for the tests shall reflect com
30、mercial label use rates. It maybe desirable to select several test substances for the evalua-tions, to compare performance between products. It may beappropriate to include other adjuvants such as surfactants, cropoils, or fertilizers, as the label allows. For example, ammoniumsulfate (AMS) is recom
31、mended on many pesticide levels.Compatibility agents will be included if necessary to create aphysically stable system.8.2 Where possible, measure the physical properties of thetest substance, particularly the dynamic surface tension at asurface lifetime age of 20 ms, shear and extensional viscositi
32、es.Test Method D3825 provides a technique for measuringdynamic surface tension. Test Method E2408 provides atechnique for measuring extensional viscosity.8.3 Use WHO 342 ppm hardness water in all samplepreparations.9. Preparation of Test Substances9.1 Mixing OrderMix the test substance components in
33、the manner described in their respective mixing instructions. Insome cases, this may involve the preparation of a pre-mix ofadjuvant(s) and active ingredient formulation. The samplesmust be mixed until homogeneous. Compatibility agents mustbe added to mixtures that do not form physically stablesampl
34、es.5The sole source of supply of the apparatus known to the committee at this timeis Sympatec GmbH, System-Partikel-Technik,Am Pulverhaus 1 D-38678 Clausthal-Zellerfeld, Germany. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your commen
35、ts will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.6The sole source of supply of the apparatus known to the committee at this timeis Malvern Instruments Ltd, Enigma Business Park, Grovewood Road, Malvern,Worcestershire WR14 1XZ, United Kingd
36、om. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.E2798 11210. Nozzles, Atomizers, and Spraying System10.1 Nozzle T
37、ypes and Use ConditionsThe nozzle selec-tion will depend on the intended end-use for the adjuvant underevaluation. Section 10.2 lists resources for nozzles whichshould be used at a minimum for the tests, depending onapplication types.Additional nozzle types and use patterns mayalso be included if ap
38、propriate for the pesticide and use type.The performance of many adjuvants depends on the nozzletype and use conditions, as well as the initial droplet size range.For example, some adjuvants may cause an increase in thecoarseness of the spray for sprays which are initially relativelyfine, or for cer
39、tain types of nozzle, while providing differentbehavior with sprays of different initial (that is, no adjuvant)conditions. Ground nozzles are usually operated at pressuresaround 40 psig. The exact pressure for a given test will dependon manufacturer recommended operating conditions and testrequireme
40、nts. Measure and record the effect of the adjuvant onspray pressure and liquid flow rate. Ground applicationsusually involve an airstream velocity up to 18 mph to facilitatesampling with number density sampling techniques.10.2 Ground Spraying SystemsFor ground-based applica-tions, ASAE S572.1 provid
41、es flat fan reference nozzles ofdifferent designations between extremely fine (XF) and ultracoarse (UC). These are often used in standard droplet size testsin Europe, North America, and other regions. Include thereference sprays for the boundaries between fine/medium andmedium/coarse sprays (which c
42、over most commercial arablespray applications) to assess whether the adjuvants cause thesprays to shift toward finer or coarser sprays. If the desired testnozzle produces a coarser spray quality, then also include thereference nozzles for the coarse/very coarse and very coarse/ultra coarse boundarie
43、s. The actual test nozzle will be specifiedby the adjuvant manufacturer, but may include one or more ofthe following nozzle types for ground-based application tests attypical recommended use conditions: flat fan, air induction,and cone. If possible, include nozzles of at least two initialdroplet siz
44、e classes. Table 1 provides examples of test andreference nozzle/pressure combinations that are used in groundapplications. All use a 50 mesh screen to prevent plugging andall yield about 0.2 gpm flow at the same given pressure.11. Procedure11.1 Droplet Size MeasurementData criteria and process-ing
45、examples are given in Practice E799. The droplet sizeanalyzer shall be used in accordance with appropriate ASTM/ISO standard test methods. Methods for using laser diffractioninstruments are given in Test Methods E1260.11.1.1 PrecisionRefer to Practice E177.11.1.2 Droplet SizeDroplets shall be measur
46、ed and char-acterized using an instrument having demonstrated accuracy inthe range of droplet size produced by the nozzle being tested.The instrument shall have a calibration verification performedwith a known source of droplets or other method. An alterna-tive method would be to measure reference p
47、articles in a liquidsuspension, as supplied by the instrument manufacturer.11.1.3 Volume Density Weighted (Spatial) Sampling TypeDroplet Measuring DeviceMeasurements can be made witha forward-light scattering (also called diffraction) instrument,imaging system, or other number density-weighted sampl
48、ingtechnique. Spray measurements shall be collected across aplane perpendicular to the nozzle axis. Instrument calibrationverification shall be checked before and after each series oftests. Manufacturer shall specify the method and technique forcalibration. Additional information is provided in Test
49、 MethodE1260.11.1.4 Number Flux Weighted (Temporal) Sampling TypeDroplet Measuring DeviceMeasurements can be made witha phase Doppler interferometer instrument, also called a PDPA,or an optical imaging system. Data shall be acquired alongthree (3) profiles through the spray, 120 apart. The size of thebeam crossing or measurement region (waist) shall be made tobe roughly equal or larger than the size of the largest dropletpresent. Selection of beam expander and transmitting lensdetermine the waist size. The instrument is optically calibratedTABLE 1
