Fumigation- Types and Methods

Here is detailed view on fumigation, their types and methods. Equipments needed during the process is also dealt here. Aeration is essential after a commodity or a place is being fumigated. Some lists of fumigants are also discussed here. we also have to know why we are practicing fumigation?

1. Presented by
V. Priyadharshini
I Ph.D. Scholar
FUMIGATION

2. ❑Apestcontrolsolutionthatfeaturestheuseoffumigantstoexterminatepestswithin
anenclosedspace(https://www.rentokil.com/pest-control-services/fumigation/).
❑Fumigationistheprocessbywhichalethalchemicalisreleasedintoanenclosedarea
toeliminateaninfestationofpests(https://homeguides.sfgate.com/what-is-
fumigation-13419242.html).
❑Fumigationisexecuted,bysuffocatingorpoisoningpest,withinanareaofspecified
spacebyusingfumigants(https://howtoexportimport.com/What-is-Fumigation-in-
Export-and-Import-219.aspx).
❑Agaswithpesticideactivity
FUMIGATION???

3. ✓Fumigation-majorroleincontrolofstoredgrainpests-unique
characteristics&greatadaptabilityofthefumigationtechniques.
✓Fumigants-effective,economicalmanagementwhereotherformsofpest
management–notfeasible.
✓Storedproductsrequireanidealfumiganttobeappliedasagasand
achievepenetrationwithinthegrainmass.
NEED FOR FUMIGATION

4. TYPES OF FUMIGATION
(https://www.markspestcontrol.com.au/fumigation-melbourne/)

5. 1.Gasfumigation:
✓Fumigants-gaseousstatesforpestcontrol.
✓Gasfumigation-enclosingaspacewithagas-proofcovering(spacefumigation),
ensurestoxicfumigantsarenotdispersedtotheexternalenvironment(Kriegarand
Sullivan,2001).
✓Methylbromide-rodents,termites,insects,nematodesandweeds.
✓Sulfurylfluoride-pestsincerealgrains,treenutsanddryfruits.
✓Gasfumigationmustonlybeattemptedafteranareaisclearedofhumansand
animals.

6. 2.Solidfumigation:
✓Solidfumigants-insectcontrol.
✓Solidfumigation-tablets,powdersorpellets(Ghosh,1989).
✓AccordingtotheWoodCenter,solidfumigants-easiertouseandsaferthangaseous
fumigantsandarelessharmfultotheenvironment.
✓AccordingtotheUSDA,solidfumigants-numeroushealthconcerns.
✓Aluminiumphosphide-allstagesinsect-pestcontrolinflour,tea,doffer,cottonand
grain.
✓Calciumcyanide-reactswithwatervaportoformhydrogencyanide.Iteffectively
eliminatesawiderangeofpests.

7. 3. Liquid fumigation:
✓Liquidfumigants-mold,pestsandinsects.
✓Liquidfumigation-sprayers,whichdisperselargequantitiesofliquidoveradesired
area.Mostliquidfumigantsaretoxictohumans,flammableandvolatile.
✓Liquidfumigationactsfasterthansolidfumigation.Liquidfumigationissafestwhen
performedoutdoorsorwithinanenclosedfumigationchamber(GibbandOsteo,2006).
✓Eg:carbondisulfide,ethylacetate,chloroform,carbontetrachloride,sulfurylfluoride,
ethylenedichlorideandmethylbromide.

8. 1)VaultFumigation–usesatmosphericorvacuumchamberstotreatinfested
commodities.(Vaults:trucks,boxcars,shipholds,warehouses,andotherstructures).
2)Fumigationbysealing–Placesitemsunderatarp.Fumigantisreleasedbeneaththe
tarpandhelduntilpestcontroliscomplete.
3)Spot(Local)Fumigation–usedtotreatsmallitemsorareaswithlighttomoderate
infestations.Spotfumigationisalsousedroutinelytopreventinfestationsfrom
developingorrecurring.
METHODS OF
FUMIGATION

9. 1)Vault fumigation:
1.1.Fumigationinatmosphericchambers:
✓Alow-costatmosphericchamberusingagastightroomundernormalairpressure
withanappropriatedoor.
✓Toolstoapply,distribute,andremovethegas.
✓Heating-Steampipesarebest(70°F).
✓Also,besuretominimizehazardstoworkersandtheenvironment.
✓Atmosphericchambersshouldnotbeconnectedtootherstructureswherefumigant
passagemayoccur.

10. 1.2.Fumigationinvacuumchambers:
❑ Vacuumchambers-large,steelstructures.Treatmentin“vacuum”ratherthanat
atmosphericpressure.Inavacuum,airpressureislower.Thisdoestwothings.
✓Itdeniesoxygentothepest.Pestsbecomestressedandareeasiertokill.
✓Thevacuumhelpsthefumigantpenetratethecommodity.Thismayreduce
fumigationtimefrom24hoursto41/2hoursdependingonthefumigantused.
❑ Inaddition,byaddingan“air-washcycle”(breakingthevacuumanddrawinga
secondvacuum),aerationaftertreatmentisalsofast.Somefumigants(suchas
phosphine)explodeundervacuumconditions.
❑ Vacuumfumigationisusedtotreatdenselypackeditemsandothermaterialsthat
aredifficulttopenetrateatatmosphericpressure.

11. Therearetwomainwaystoconductvacuumfumigation:
1.Sustained-vacuumfumigation:Reducethepressureinsidethechamberand
introducethefumigant.Theslightlyreducedpressure(vacuum)ishelduntiltheend
ofthetreatment.
2.Restored-pressuremethod:Lowerthepressure,introducethefumigant,andthen
restorethepressureinoneoffourways.

12. a)GradualRestoration–Releasethefumigantandthenslowlyintroduceairuntilthe
airpressurereturnstonormal.Thisusuallytakestwotothreehours.
b)DelayedRestoration–Holdthevacuumforabout45minutesfollowingdischargeof
thefumigant.Then,allowairtorapidlyenterthechamber.
c)ImmediateRestoration–Justafterreleasingthefumigant,rapidlyletairintothe
chamberbyopeningoneormorevalves.
d)SimultaneousIntroductionofAirandFumigant–Usespecialmeteringequipment
toreleaseamixtureofairandfumigantintothechamber.

13. A portable vaccum chamber consists of:
•Avacuumsuchasa“shopvac”orotherhigh-capacityvacuumcleaner
•Twopiecesofheavy-dutyvinylsheetingthatyoucanclamporziptogether(similarto
foodstoragebags)
•Fumigationdispensers
•Connectinghoses
•Asecuritylock
•Agasconcentrationmonitoringvalve
•Acarryingcase,and
•Agasdischargestandpipe
Portablesystemsallowyoutodevelopavacuumbetweenthelayersofvinyl.The
vacuumpullsthevinyltightaroundthecommodity.Oncethevacuumreachesthe
optimallevel,youcanapplythefumigant.

14. Aeration of Fumigation Chambers
1.Indoor:Installintakeandexhaustpipesforsafeaeration.Thesepipesleadtotheoutside.The
intakepipe-drawfreshairinwhileblowingfumigant-treatedairoutside.Turnonaircirculation
equipmentinthechambertoexchangeairbetweenthechamberandtheoutside.
2.Outdoor:Aerationisstraightforward.Simplyopenthedoorslightlyandturnontheblower.Be
suretoproperlyopenthedoorsoitdoesnotaccidentallyclose.

15. 2) Fumigation by Sealing
1.“Tape and seal” fumigation
2.Tarpaulin fumigation
Turninganentirestructure–warehouse,boxcar–intoatemporaryfumigationchamber.
Fumigationbysealingaccomplishesthisbyworkingonlywithbuildingsthatarein
goodrepair.Workersfindandsealallleakyspotswithfumigationtape.Structural
fumigationbytarpingcreatesanairtightenvironmentbyplacingatentovertheentire
structure.

16. 1.Tapeandsealfumigation
(A)SilosandGrainBins:
✓Whensealinggrainbinsandsilosforfumigation.Propersealing-successand
failureofatreatment.Theseincludealongwalls,roof-walljunctures,seams,roof
ventilators,bindoors,aerationfans,andthroughothergaps.Whensealingthese
gapswithfumigationtape,itisoftenhelpfultoapplytapeprimerfirst(adhere
better).
✓Unlikeothertypesofgrainstoragestructures,woodenbinsareoftentooleakyfor
tape-and-sealfumigation.Woodenbinsmayhavetobetarpedtoretainenoughgas
forthetreatmenttobeeffective.

17. ✓Onceagrainbinorsiloissealed,releaseyourfumigant.Somefumigantsare
heavierthanairandsorequirespecialrecirculatingequipment(blowers)to
adequatelydistributethemthroughoutagrainmass.First,turnthemonto
establishairflow.Then,introducethefumigantonthehigh-pressuresideofthe
blowers.Runtherecirculatingsystemuntilthefumigantisthoroughlydistributed.
✓Thesedevicesregulatethetemperatureandmoisturecontentofthegrain.During
fumigation,youcanusethemtodistributefumigantsthroughoutthegrainmass.
Otherstoragestructuresmaynothavesuchsophisticatedsystems.

18. (B)Warehouse:
✓Startbysealingthestructureastightlyaspossible.
✓Polyethylenesheetsshouldbe2to4milsthick.Thisthicknesswillclingtothe
buildingbetterthanthickermaterial.
✓Usefumigationtapetosealsmallcracksandholes.
✓Checkforleaks.
✓Setupmonitoringequipmentbeforereleasingthefumigant.
✓Chooseacommoditycontainerfarfromthefumigantreleasesite.Theninserta
metaltubeintothecontainer.Attachaplastictubetothemetaltube.Runtheplastic
tubeoutsideofthebuilding.Takegasreadingswithadetectorspecifictothe
fumigantyouareusing

19. ✓Gasconcentrationsaremeasuredinpartspermillion(ppm).Iftheconcentrationof
gasistherightppmattheendoftheexposureperiod,allpestsshouldbedead.
Treatmentiscomplete.
✓Readthelabelinformationofeachproductyouusetodeterminethedosageand
exposuretimes.

20. (C)WheeledCarriers:
✓Usefumigationtape,liquidadhesive,orcaulkingtosealanygaps.Secureaprecut,
twoorfourmilpolyethylenesheetovertheentiredoor.Computethevolumeofthe
containertodeterminethedosage.
✓Applythefumigant.Everyproductisdifferent.Readthelabelinformationto
determinehowtoapplytheproductyouareusing.Next,coverthelastdoorwith
polyethylenebeforeclosingandsealingitwithfumigationtape.
✓Placeawarningsignoneachdoor.(dateandtimeoffumigationandthename,
address,andtelephonenumberoftheapplicator).

21. (D) Ship Fumigation:
✓ Shipfumigationtreatsgoodswhiletheyarestillonboard.Thisavoidsextra
loadingandunloading.Thisisparticularlyimportantforproductsarrivingfrom
overseas.Shipfumigationinvolvesmanypeople.Closecooperationwiththe
responsibleshipofficer,shipagent,USDA,andCoastGuardinspector(ifinvolved)is
essential.YoumayalsoneedtonotifythePortAuthorityandthelocalfireandpolice
departments.
✓ Shipboardfumigationishighlyspecialized.Theproblemsencounteredand
techniquesusedinshipfumigationareunique.Inmanycases,youmaywanttohirea
companythatspecializesinshipfumigation.

22. 2. Tarpaulin Fumigation
Tarpaulinfumigationtreatssingleitemsorentirestructures.Itworksbyplacinga
semipermeablematerialoveraninfesteditemorstructure,sealingtheedges,andthen
releasingfumigantbeneaththetarp.

23. Types of Tarpaulins
Impreganted Nylon
1.Resistripping&reusable.
2.Clamp/tapetogethermany
sections.
3.Expensive
4.Heavier
Polyethylene sheets
1.3milthicknessorless-indoor.
2.3milthickness–preferredoftenas
itislessexpensivetonylontarps.
3.4&6milthickness–outdoor.
4.Easydisposable.

24. Indoors:
✓Tarpaulinfumigationiseasiestandmosteffectiveindoors.
✓Protectionfromwindandrainiscritical.
✓Postwarningsignsandmonitorthearearegularly.
Outdoors:
Outdoor tarp –stronger and durable (PE sheets : 4 –6 mil thickness).
1.Clearpolyethylene-brittlefromUVraysofthesun.Raysofsunlightcanconcentrate
throughwaterdropsoncleartarpsandcausefires.

25. 2. Black polyethylene–resistant to sunlight, and it is not transparent. If the tarp spans
several stacks, it may conceal gaps between the stacks or other voids. Persons working
on top of the tarp must be careful not to fall through.
Challenges:
✓Difficulttoobtainagoodgroundsealoutdoors.
✓Sandandwatersnakesareoftenlesseffectivebecausethegroundisusuallyporous
anduneven.Instead,placealayerofloosesandonthetarpskirttoobtainagoodseal.

26. Ground Seals:
Inadditiontopropertarpselection,alsoconsiderthetypeofgroundsealyouwillneed.
✓Smooth,concreteandasphaltsurfaces-Baseforagoodgroundseal.
✓Wood/Soilsurfaces-Donot.
Withwood,andfrequentlywithsoilsurfaces,itisnecessarytoplaceasectionof
thetarpbeneaththeitemtobefumigatedaswellasoverthetopoftheitem.Otherwise,
gasmayescapethroughthewoodorsoil.Thereareseveralwaystoobtainagood
groundseal.
1.Covertheinfesteditemallowingatleast18inchesoftarptoskirtoutfromthebase.
2.Then,layloosesand,sandsnakes,orwatersnakestoholdtheskirttotheground
surface.

27. 3.Snakesaretubesofclothorplasticfilledaboutthree-fourthsfullwithsand,gravel,or
water.Alltypesofsnakesshouldoverlapeachotherabout11/2feet.
4.Sometimesyoucanattachadhesivefumigationtapedirectlytothefloor.However,
youwillstillneedsand,gravel,orwatersnakestopreventthetarpfromblowingoff
duringtreatment.
5.Occasionally,youmayneedtotreatanitemthatistooclosetoawalltoobtainagood
groundseal.Inthiscase,movetheitemandsealthetarpproperlytothefloor.

28. Tarpaulin Aeration
✓Placeablowerononeendoftheload.Makeanopeningontheoppositeendby
liftingthetarp.Thenturnonthebloweranddischargethefumigant.
✓Ifyouchoosenottouseablowerorcrossventilation,aeratetheitemorareaby
liftingthetarpatthecorners.Then,slowlyraisethesidesuntilthetarpis
completelyremoved.
✓Ifaerationoccursoutsideandthereisabreeze,payattentiontowhichwaythe
breezeisblowing.Alwayslifttheendorsideofthetarpoppositethedirectionof
windmovement.

29. 3. Spot (Local) Fumigation
Spotfumigationistheshort-termtreatmentofmachineryandsmall
storageswithtoxicgases.Spottreatmentsworkbyinterruptingthelife
cyclesofinsectpests.Usespotfumigationtocontrolstoredproductpestsin:
❑Bins, silos, and holding tanks
❑Elevator boots and heads
❑Filters
❑Conveyors
❑Spouting
❑Purifiers
❑Food processing equipment
❑Sifters, rollers, and dusters, and
❑Relatedequipmentinmills,food
andfeedprocessingplants,
breweries,andsimilarindustries

30. ✓ Beforetreatment,runthemachinerytoemptytheprocessstream.Inmills,turn
offthefeedandallowthemilltorunfor30to45minutes.Duringthisperiod,use
rubbermalletstotaponthespouting,elevatorlegs,andsifters.Thiswillhelptoloosen
productthatistrappedinside.Checkoutletchannelsinthesifterstobesuretheyare
notblockedorchoked.
✓ Next,sealtheequipment-preventfumigantfromescaping.Closedustcollector
andfilterventstokeepthefumigantwithinthemachinery..Thermalcurrentsand
draftscancauseaspotfumigationtofail.Gasmayescapebeforereachingalethal
concentrationwithinthemachinery.

31. Aeration After Spot Fumigation
✓Turningonventilatorsandopeningdoorsandwindowsinthetreatedarea(s).
Removecoversfrombins,vessels,andotherequipment.Turnondustcollectorfans.
✓Aerationafterspotfumigationisgenerallycompleteinlessthanonehour.
✓Alwayscheckgaslevelswithanapprovedgasdetectorbeforereentry.

33. (DPPQ&S , 2017)

34. (https://safetyculture.com/topics/ppe-safety/)

35. FUMI CELL
BAG
PELLET
DISPENSER
FUMI DISC WIRE BASKET
J-SHAPED FAN
DISPOSAL DRUM RAILCAR HATCH AERATION SCREEN
GAS DETECTER
EQUIPMENTS
(https://indfumco.com/products-labels/products/fumigant-application-
equipment/)

36. Phosphinegasiscolorlessandhighlytoxictoallstagesofinsectandanimallife.Ithasa
distinctgarlicorcarbideodour(AlP&MgP).
Formulations:
Gasbag:34g 11g
Tablets:3g 1g
Pellets:0.6g 0.2g
Pellet
Tablet
Gas bag
PHOSPHINE

37. Dosageguidelinesofalp
Reason:
✓Aluminumphosphide-akeystatusintheInternationalmarket.
✓Indiaisentirelydependentonphosphineasthefumigantfor
disinfestinggrainstacks-low-priced,easytoapplyanddoesnotaffect
thequalityevenafterrepeatedapplications.
Product No. per 1000 Cu.ft. No. per 1000 bu.
Gas bag 13 16
Tablets 145 180
Pellets 725 900

38. ✓Calculatethecubicvolumeofspacetotreat.Then,countouttherequirednumberof
pellets,tablets,orbags.
✓Alwaysweargloveswhenhandlingphosphidetabletsorpellets.
✓Placethepellets,tablets,orbagsontoatrayorsheetofcardboard.Slipthetrayunder
thefumigationtarporinsidethefumigationchamberorstructure.
✓Themoistureintheairwillliberatephosphineinaboutoneday,dependingonthe
temperatureandhumidity.
Exposure:
12 –48 hours. If gas concentrations are lower than required after 72 hours, extend
the fumigation period.

39. ✓Magnesiumphosphidereleasesphosphinefasterthandoesaluminumphosphide.
Hence,recommendedforfumigationincooland/ordryconditions.
✓Phosphineisnoteffectiveattemperaturesbelow40°F.
Detection:
Glassdetectortubes
✓0.1–40ppm
✓50–2000ppm

40. (Chadda et al., 2016)

41. 1. Farm bin
✓Surface application.
✓Tablet and pellets probed into grain using 5 –7 ft PVC pipe
(20-50 tablets, 100-250 pellets).
2. Flat storages
✓Surface application.
✓Probes inserted vertically at intervals along the length and width of flat storage.
✓Place 25 % dose in the floor level aeration ducts.
3. Vertical storages
✓Hand or automatic dispenser of pellets or tablets on the headhouse or gallery belt.
✓Bins requiring more than 24 hrs to fill -probing or surface fumigation.

42. 4. Mills, food processing plants and warehouses
✓Place trays or sheets of kraftpaper or foil up to 12 sq.ftin area on floor throughout the
structure.
✓Spread weevil-cideon the sheets at a density of no greater than 30 tablets or 150 pellets
or 3 gas bags per sq.ft.
5. Railcars, containers, trucks, vans and other transport vehicles
✓Gas bags attached to walls or other support.
✓Tape across the gas bag end only (disc or board).

43. 6.TarpaulinandBunkerfumigation
✓Appliedtotarpedstacksorbunkerstorageofbulkcommoditythroughslitsinpoly
covering.
✓Slitssealedproperly.
FORMULA:
Amount of fumigant (g) = Vol. of . Chamber (ft³) ×Dosage (g/ft³)
% fumigation release ×1000

44. BRAND NAMES OF PHOSPHINE
Quickphos,Celphos,Fostox,Fumitoxin,Phostek,Phostoxin,Talunex,Fieldphos
&Weevil-Cide.

45. ✓Methylbromideisacolorless,odorless,tastelessgasandhassettlingoutinlow
places.Fansareneededtonoirritatingqualitiestoindicateitspresence.
✓Thegasis3.3timesheavierthanairandtendstosettlingoutinlowerplaces.
✓Fans–ensurethoroughmixingofMBr.
Formulations:
✓Methylbromide-compressedliquidin11/2-poundcansorincylinderscontainingup
to200lbs.
✓MBr+Chloropicrin;avoidusingchloropicrinonfoodorstoredcommodities.
METHYL BROMIDE

46. Applications:
✓Smallcansofmethylbromide-smalljobs.Aspecialapparatus-puncturesthecan,and
polyethylenetubingtransfersthegasfromthecanintothefumigationenclosure.
✓Forlargerjobs-usecylinders.First,attach1/4-inchcoppertubingtothecylinder
usingagastightfitting.Then,formthetubingintoa25-footcoilandimmerseitin
waterheatedto150°F.Thetubingfromtheheatertothefumigationchambershouldbe
eithercopperorpolyethylene.
Methylbromideworksquickly.Exposuretimesof24hoursorlessarenormal.
Methylbromideliquidvaporizesintogasattemperaturesabove39°F.Forthisreason,
donotusemethylbromidewhenthetemperatureinthefumigationareaisbelow40°F.

47. Detection:
✓Halidegasdetectors,
✓Colordiffusiondetectortubes
✓Thermalconductivityanalyzers(TCAs)
HALIDE GAS
DETECTOR
THERMAL CONDUCTIVITY
ANALYZER
COLOR DIFFUSION
TUBES

48. Sulfurylfluoride(ProFume®)isacolorless,odorless,andtastelesstoxicgas.Itis
heavierthanairandtendstoinitiallysettleinlowareas.
Formulations:
Gascontainers
Applications:
✓ Introducesulfurylfluoridefromtheoutsidethroughtubes.
✓ Usepolyethylene,polypropylene,orstrongnylontubingwithaninternal
diameterof1/8to1/4inch.
SULFURYL FLUORIDE

49. ✓Thetubingshouldhaveaminimumburstpressureof500poundspersquareinch
(PSI).
✓Therateoffumigantreleasedthroughlargertubingwouldbetoogreatforgoodgas
distribution.Placefansthroughoutthefumigationarea.
✓Runthefansduringintroductionandforatleast60minutesafterward.
✓Donotusesulfurylfluorideattemperaturesbelow40°F.
✓Topreventdamage,donotapplysulfurylfluoridedirectlytoanysurface.
Detector:
Thermalconductivitydetector(Fumiscope)

50. (Rajendran, 2016)

51. ✓Fumigation–Aneffectivemanagementagainststoredproductpests.
✓Theconditionofthefumigationsheet/cover,sealingstandardsandthetypeoffloor
surfacedeterminethefumigantslevelsmaintainedduringtheexposureperiodand
therebyhelpsinthemanagementofinsects.
✓Gasmonitoringisimportantduringfumigationtopredictitssuccessandto
supplementdosageortoextendtheexposureperiod,ifnecessary.
CONCLUSION