Wood Preservation and Wood Products Treatment Training …...Treatment Training Manual. G. Thomasson, J. Capizzi, F. Dost, J. Morrell, and D. Miller. wood readily may be damaged and

EM 8403 • Reprinted October 1998$1.50

Wood Preservation andWood Products TreatmentTraining Manual

ContentsProperties of wood ..........................................1

Pests that damage wood .................................1Wood-inhabiting fungi ....................................... 2

Wood-destroying fungi ......................................... 2Brown rot ............................................................ 2White rot ............................................................. 2Soft rot ................................................................. 2

Wood-staining fungi .............................................. 2Sap-staining fungi ............................................. 2Mold fungi .......................................................... 2

Chemical stains .................................................... 3Insects .................................................................... 3

Termites ................................................................... 3Subterranean termites ....................................... 3Dampwood termites ......................................... 3

Carpenter ants ........................................................ 3Beetles ...................................................................... 3

Powderpost or Lyctus beetles ......................... 3Anobiid beetles .................................................. 3Roundheaded and flatheaded borers ............. 3

Marine borers .......................................................... 3

Controlling pests that damage wood ........ 3Moisture control .................................................. 4Using naturally resistant wood ......................... 4Chemical control.................................................. 4

“General use” pesticides ....................................... 4“Restricted use” pesticides ................................... 4

Creosote .............................................................. 4Pentachlorophenol (penta) ............................... 4Inorganic arsenicals .......................................... 5

Protecting human health..........................5Hazards to applicators..................................... 5Toxic effects of preservatives .......................... 5First aid .............................................................. 8Protecting the applicator ................................. 8

Personal hygiene .................................................. 8Protective equipment and clothing ................... 8Special precautions .............................................. 9

Limits on use ..................................................... 9Material Safety Data Sheets (MSDS) .............. 9Voluntary Consumer AwarenessProgram .........................................................9

Inorganic arsenicals ............................................. 9Creosote ............................................................... 10Pentachlorophenol ............................................. 10

Protecting the environment ................... 11Waste disposal ................................................. 11Storage and disposal of containers ............... 12Spills .................................................................. 12Environmental exposure ................................ 12

Pentachlorophenol ............................................. 12Arsenicals ............................................................ 12Creosote ............................................................... 12Groundwater pollution ..................................... 12

Definitions .................................................... 13

For further reading ...................................... 14

Wood Preservation and Wood ProductsTreatment Training ManualG. Thomasson, J. Capizzi, F. Dost, J. Morrell, and D. Miller

F ederal and State regulationsestablish standards that youmust meet before you legally

can use certain pesticides. EffectiveNovember 1986, Federal regula-tions administered by the Environ-mental Protection Agency (EPA)restrict the sale and use of certainpreservatives to ensure that onlyproperly trained applicators, orpeople under their direct supervi-sion, will have access to them.

Wood preservatives affected bythese regulations are creosote,pentachlorophenol (penta), andinorganic arsenicals. This publica-tion will help those preparing forthe wood preservative pesticidelicensing examinations adminis-tered by the State departments ofagriculture in the Pacific North-west.

Wood pesticides (preservatives)extend the life of wood products byprotecting them from damage byinsects, fungi, marine borers, andweather. Preservatives are appliedon the basis of how and where theproducts will be used, the expectedconditions of exposure to wood-destroying agents, and the cost peryear of service life.

Crossties, poles, posts, and otherwood products that contact theground or are exposed to theweather must be protected withpreservatives to ensure a reasonableservice life. Other wood productsnot in contact with the ground maybe treated as a precautionary mea-sure even though they are notexposed to moisture and weather.

Long-term tests and experienceshow the levels of protection

needed for various products anduses. These guidelines becomeindustry-wide when they areaccepted by the following groups:• Groups that use the treated

products• Regulatory agencies• Wood-preserving organizations

There are many standards andspecifications to control the qualityof treated wood and protect thepurchaser. Federal and Statespecifications and requirements ofthe American Wood PreserversAssociation are the regulationsmost commonly used.

Properties of woodCrosscut a Douglas-fir or cedar

tree, and inside the bark you’ll finda zone of lighter wood (sapwood)surrounding a core of darkercolored wood (heartwood).Fast-growing trees usually havedeeper sapwood than slow-growing trees.

Ninety percent of wood is madeup of minute, hollow fibersoriented lengthwise along the treestem. These fibers, 1⁄5 inch long, are100 times longer than wide.Through them, the tree transportswater and nutrients verticallywithin the tree.

The remaining 10 percent of thewood is composed of short, hollow,brick-shaped cells oriented from thebark towards the center of the treeas ribbons of rays of unequal heightand length. These rays distributefood, manufactured in the leavesand transported down the innerbark, to the growing tissues

between the barkand the wood.

Wood is composed of a complexmixture of substances, but the mainconstituent of all wood is a complexsugar called cellulose. This materialserves as the primary source ofenergy and nutrition for manyforms of life on this planet. Peopleuse this same source of energy, notas food but as heat, when they stokeup the wood stove or fireplace.

Pests that damage woodPeople use wood for millions of

things other than as a heat source.Under proper use conditions, woodcan give centuries of good service;under unfavorable conditions,

This publication was revised from aUniversity of Georgia CooperativeExtension Service publication by GaryThomasson, Extension entomologist,Washington State University, and thefollowing from Oregon State Univer-sity: Joseph Capizzi, Extension entomolo-gist emeritus; Frank N. Dost, Extensiontoxicology and agricultural chemicalspecialist emeritus; Jeffrey J. Morrell,associate professor of forest products;and Donald J. Miller, professor of forestproducts emeritus.

wood readily may be damaged anddestroyed by fungi, insects, andmarine borers. These pests canattack in many ways, so wood mustbe protected to ensure maximumservice life when used underconditions favorable to these pests.

Wood-inhabiting fungiWood decay, mold, and most

sapwood stains are caused byfungi. These organisms, which feedon living or dead wood and pro-duce spores (microscopic seeds),are distributed by wind and water.The spores can infect moist woodduring storage, processing, or use.All fungi that grow on wood havetwo basic requirements:• Favorable temperature. This

usually ranges between 50 and90°F. Optimum temperatureconditions generally are between70 and 90°F. Wood usually issafe from decay at temperaturesbelow 35 and above 100°F.

• Adequate moisture. Fungi willnot attack dry wood (wood witha moisture content of 19 percentor less). Decay fungi require awood moisture content of about30 percent or the generallyaccepted fiber saturation point ofwood.Thus, air dried wood, usually

with a moisture content not exceed-ing 19 percent, and kiln-dried woodwith a moisture content of 15 per-cent or less, usually can be consid-ered safe from fungal damage.

The many fungi that develop onor in wood can be divided into twomajor groups based upon thedamage they cause: wood-destroying fungi (decay fungi) andwood-staining fungi (sap-stainingfungi, mold fungi).

Wood-destroying fungiBoth the sapwood and heart-

wood of most tree species aresusceptible to decay, and

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unprotected sapwood of all treesdeteriorates rapidly in warm, moistsoil. Douglas-fir, western larch,western hemlock, and most otherspecies also have nondurableheartwood. Heartwood of cedar,redwood, and a few other species isdurable, lasting three to five timeslonger than nondurable woods.

Decay fungi may grow in theinterior of the wood or appear onwood surfaces as fan-shapedpatches of fine, threadlike, cottonygrowths or as rootlike shapes. Thecolor of these growths may rangefrom white through light brown,bright yellow, and dark brown.

The spore-producing bodies maybe mushrooms, shelf-like brackets,or structures with a flattened, crust-like appearance. Fine, threadlikefungal strands grow throughout thewood and digest parts of it as food.

In time, the strength of wood isdestroyed. For example, untreatedpoles or posts first rot in the sap-wood just below the groundline,where moisture and temperatureare most favorable for fungalgrowth. Once established, thefungal strands may extend severalinches or more into the heartwood.

Decay will stop when thetemperature or moisture conditionsin the wood are unfavorable forfungal growth; however, decay willresume whenever the conditionsbecome favorable.

Wood-decay fungi can besegregated into three major catego-ries: brown rots, white rots, and softrots.

Brown rot fungi break down thecellulose component of wood,leaving a brown residue of lignin.Brown-rotted wood can be greatlyweakened even before decay can beseen. The final stage of wood decayby the brown rots can be identifiedby the dark brown color of thewood, excessive wood shrinkage,cross-grain in cracking, and by theease with which the dry wood

substance can be crushed to pow-der.

These fungi probably are themost important cause of decay ofsoftwood species used in above-ground construction in this country.(When dry, brown rot sometimes iscalled dry rot. This is a poor termbecause wood will not decay whenit is dry.)

White rot fungi break downboth lignin and cellulose in woodand have a bleaching effect, whichmay make the damaged woodappear whiter than normal.

Soft rot fungi usually attackgreen, water-saturated wood,causing a gradual softening ofwood from the surface inward. Thedamage done by these fungiresembles that caused by brown rotfungi.

Wood-staining fungiThe primary damage caused by

these fungi is simply discolorationof the wood. They have little or noeffect on its strength.

Sap-staining fungi penetrateand discolor sapwood, particularlyamong the softwood species. Unlikestaining by mold fungi, typical sapstain can’t be removed by brushingor planing. Sap stain fungi maybecome established in the sapwoodof standing trees, saw logs, lumber,and timbers soon after they are cutand before they can be adequatelydried. One of these fungi, bluestain, is carried to trees by pinebeetles, thus infecting trees beforethey are cut.

Where appearance of the wood isimportant, sap-stained wood maybe unfit for use.

Mold fungi first become notice-able as green, yellow, brown, orblack fuzzy or powdery surfacegrowths on softwoods. Freshly cutor seasoned stock, piled duringwarm, humid weather, may benoticeably discolored within a fewdays. Although brushing or planing

will remove the stain, these fungican increase the capacity of wood toabsorb moisture, thereby increasingthe likelihood of attack by decayfungi.

Chemical stainsAlthough they may resemble

fungal blue or brown stain damage,chemical stains are not caused byfungi; rather, they’re caused bychemical changes in the woodduring processing or seasoning.Chemical stains can downgradelumber for some uses, but thesestains usually can be prevented byrapidly drying the wood at rela-tively low temperatures duringkiln-drying.

InsectsSeveral kinds of insects attack

living trees, logs, lumber, andfinished wood products for foodand shelter. The most importantpests of wood and wood productsinclude termites, carpenter ants,and various beetles.

TermitesTermites use wood for both food

and shelter. Nationally, termites arethe most destructive of all woodpests. Although they are notconsidered the number one woodpest insect in this area, termitesaccount for a significant amount ofstructural damage in the PacificNorthwest. The two major speciesof concern in the PNW are subterra-nean termites and dampwoodtermites.

Subterranean termites canattack any unprotected wood orwood product. They live in andobtain their moisture from the soil.

Although subterranean termitesprefer the soil environment, theywill build mud tubes over exposedsurfaces from the soil to a foodsource.

Dampwood termites live in thewood on which they feed and relyon the wood as a source of water;consequently, these termites attackonly wood with a high moisturecontent—but once established, theycan extend their activities intosound, dry wood.

Carpenter antsThese are the most destructive

insects of wood and wood struc-tures in the PNW. They usually livein stumps, trees, or logs, but willinfest virtually any wood. Theseinsects cannot use wood for food,but they often are confused withtermites. There are, however,several distinct physical differencesbetween these two groups ofinsects. Ants have “elbowed”antenna; termites do not. Ants havevery narrow waists, but termites’bodies are broad.

BeetlesPowderpost or Lyctus beetles

attack both freshly cut and sea-soned hardwoods and softwoods.Adults lay eggs in the wood pores.Emerging larvae burrow throughthe wood, making tunnels packedwith a fine powder. The Pacificpowderpost beetle damagesstructures from California toAlaska, feeding mainly on well-seasoned wood.

Anobiid beetles attack soft-woods in damp or poorly ventilatedspaces beneath buildings.

Roundheaded and flatheadedborers infest live trees as well asrecently felled or dead, standingsoftwood trees. They can causeconsiderable damage in rusticstructures and some manufacturedproducts. Some species live inwood from 2 to 40 years.

Marine borersSubmerged portions of marine

pilings, wharf timbers, and woodenboats are damaged extensively by agroup of animals known collec-tively as “marine borers.”Untreated timbers can be infestedand destroyed by these organismsin less than a year. Major marineborers in the Northwest includespecies in the Mollusca (related toclams and called “shipworms”) andthe Crustacea (related to crabs orsow bugs and called “gribbles”).

Shipworms drill tunnels in woodand line them with a thin shell-likesubstance. The giant shipwormBankica setacea and species ofTeredo are the most commonforms.

Gribbles mine the outer part ofpiling and other marine structures.Attack takes place from the mudline to the upper tidal level. Com-mon “gribble” species includeLimnoria lignorum.

Controlling peststhat damage wood

Wood should be protectedwhenever it is used where it will besubject to pest attack. This protec-tion can be achieved by controllingthe wood moisture content, usingwood that’s naturally resistant tothe pests, or by treating the woodwith a chemical preservative.

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Moisture controlThe moisture content of

living trees and the woodproducts obtained fromthem may range fromabout 30 percent to more

than 200 percent. Timberor logs stored for

extended periodsbefore processingcan be protectedfrom fungi andinsects by keep-ing the logssubmerged inpond water or by

subjecting them toa continuous water

spray. The water reduces theoxygen content and temperature ofthe logs to levels below thoseneeded for pest development.

Much of this moisture must beremoved for most uses. Greenlumber usually is seasoned or driedto do the following:• Prevent development of stain

and decay organisms• Reduce insect damage• Control wood shrinkage• Reduce weight and increase

strength• Prepare wood for chemical

preservative treatmentsThe moisture content of wood

usually is reduced either by air-drying in a yard, shed, or pre-drier;or by drying in a kiln, retort, orradio frequency drier. The mostefficient and widely used system iskiln-drying because it offers bettercontrol of air movement, tempera-ture, and drying rate than doesair-drying.

Although kiln-drying is moreexpensive than air drying, it’s muchfaster, and it provides better qualityand more uniform drying. Further-more, unless lumber is properlystacked and protected, air-drying

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may result in surface cracking(checking), end cracking, warping,staining, and discoloration due toweathering.

Even after being well seasoned,wood may again reach a moisturelevel favorable to pests, especially ifexposed to rain or prolonged highhumidity and favorable tempera-tures.

Using naturallyresistant wood

The sapwood of all native treespecies and the heartwood of mostspecies has low natural resistance todecay; however, the heartwood ofsome trees, such as cedar andredwood, is quite resistant to decay.These species are resistant—butdefinitely not immune—to attackby decay fungi and insects. Unfor-tunately, these naturally resistantwoods usually are quite expensive.

Chemical controlThe proper application of

chemical preservatives can protectwood from decay and stain fungi,insects, and marine borers, thusprolonging the service life of woodfor many years.

The effectiveness of preservativetreatment depends on the chemicalformulation selected, the method ofapplication, the proportion ofsapwood to heartwood, the mois-ture content of the wood, theamount of preservative retained,the depth of chemical penetration,and the distribution of the chemicalin the wood.

Sapwood of most commerciallumber tree species accepts preser-vatives much better than heart-wood, and softwood speciesgenerally can be more uniformlytreated than hardwood species.Preservative treatment by pressureusually is required for woodexposed to high risk of attack byfungi, insects, or marine borers.

“General Use” pesticidesThere are hundreds of pesticide

products registered for applicationto wood and wood products in thePNW. Most of these have beendesignated “General Use” pesti-cides. Exposure to such chemicals isconsidered less hazardous thanexposure to “Restricted Use”pesticides.

“General Use” pesticidescommonly used by the woodpreservation industry are coppernaphthenate and copper 8 quino-linolate; 3-iodo propynyl butylcar-bamate, zinc naphthenate, andsodium octaborate tetrahydrate alsoare used. Unlike wood treated with“Restricted Use” preservatives,copper 8 quinolinolate has beenapproved for food-contact usessuch as for boxes, crates, pallets,truck decking, and related usesinvolving the harvesting, storage,and transportation of food.

“Restricted Use” pesticidesThree groups of chemical wood

preservatives have been designated“Restricted Use” pesticides. Thisdesignation includes the require-ment that only those who aretrained and licensed may purchaseor use creosote, pentachlorophenol(penta), and inorganic arsenicals.

Table 1 summarizes the advan-tages and disadvantages of thesethree pesticides.

Creosote is an oily liquid pro-duced when coal is heated in theabsence of air; it’s the by-product ofmaking coke from bituminous coalfor the steel industry. This materialusually is used as a preservative forrailroad ties, large timbers, fenceposts, poles, and pilings.

Pentachlorophenol (penta) is theproduct of a complex chemicalprocess. It’s insoluble in water, soit’s generally dissolved in petro-leum or other organic solvents thatwill penetrate wood. However,

this versatile chemical also isformulated as a water-emulsifiablecompound or as a water-solublesalt (ammonium pentachloro-phenate) to protect freshly sawnlumber from sap stain fungi.

Penta is used to commerciallytreat poles, crossarms, lumber,timber, and fence posts. It’s notrecommended for use in marineinstallations, or close to plants, andit may not be used inside buildingsexcept as indicated on page 11.Penta is no longer available for thedo-it-yourselfer.

Inorganic arsenicals are preser-vatives consisting of combinationsof copper and arsenic. The mostcommonly used compounds arechromated copper arsenate andammonical copper arsenate. Thesepreservatives are water-soluble; butwhen they’re applied to wood, theybecome fixed in the wood in aninsoluble form. The copper pro-vides protection against attack byfungi, and the arsenic preventsinsect attack. These preservativesare considered highly versatile, andtheir use is expanding.

Protecting human healthMost chemicals used to protect

wood from insects and decay mustbe toxic to be effective. The goal isto select chemicals and methodsthat will control the pests withoutharming the applicator, the user,the public, pets, plants, or theenvironment.

It’s the responsibility of themanager of any wood-preservingoperation to ensure that the properhandling procedures, protectiveclothing, and necessary safetyequipment are provided to work-ers, to protect their health and toconform with label instructions.

The EPA-approved labelingand mandatory Material SafetyData Sheets (MSDS’s, see page 9)for wood preservatives are theprimary sources of information on

application methods, precautionarymeasures, emergency first aid, anddisposal instructions.

The label is a legal document andits provisions are enforced by Stateregulatory agencies. Therefore,make sure that labels for eachformulated product used in a woodtreatment operation are readilyavailable; all responsible personnelshould be thoroughly familiar withtheir contents.

Hazards to applicatorsAll handlers of wood preserva-

tives must know about the potentialhazards and the precautionsnecessary when working with thesechemicals. Those who apply thechemicals are most subject toexcessive exposure; those who usethe wood are at far less risk frompreservative exposure. Therefore,it’s especially important for thosewho apply preservatives andhandle recently treated wood tominimize their exposure to thesechemicals.

Exposure to wood preservativescan occur in a variety of ways:during mixing and handling thechemicals, entering pressure-treatment cylinders, workingaround preservative spraying ordipping operations, handlingfreshly treated wood, cleaning orrepairing equipment, or disposingof wastes. Closed systems forhandling the chemicals andmechanically handling treatedwood reduce potential exposurebut do not eliminate accidentalexposure for workers.

Like other pesticides, woodpreservatives can enter the bodythrough the mouth (oral), throughthe skin or eyes (dermal), orthrough inhalation (respiratory).Since most preservatives have astrong odor and taste, accidentalingestion of a dangerous amount ofthese chemicals is very unlikely.The more likely routes of exposure

would be through skin contact orby inhaling preservative vapors,dust, or other contaminatedparticles.

Human skin varies in thicknessand other characteristics from oneplace to another on the body. Theskin also varies in its ability toabsorb chemicals. The eye, eyelids,and the groin area will absorbalmost 100 percent of some chemi-cals while the hand, especiallythe palm, will absorb less than10 percent of the same chemicals.The addition of organic solvents toany preservative will enhance itsability to penetrate human skin.

Human lungs consist of a verylarge, membranous surface areawell supplied with blood vessels.Any chemical vapor or minuteliquid droplets taken into the lungswill be absorbed into the blood-stream very rapidly.

Toxic effects of preservativesThe toxic effects of the chemicals

can be either acute, based on high-level, short-term exposure; or theycan be chronic, based on low-level,long-term exposure. Humanexposure to preservatives canproduce both acute and chronictoxicity.

Use pesticides safely!• Wear protective clothing and

safety devices as recommendedon the label. Bathe or showerafter each use.

• Read the pesticide label—even ifyou’ve used the pesticide before.Follow closely the instructionson the label (and any otherdirections you have).

• Be cautious when you applypesticides. Know your legalresponsibility as a pesticideapplicator. You may be liable forinjury or damage resulting frompesticide use.

5

6

Table 1.— a ute and chronic), special precautions, and limits on use.

Pesticide a pecial precautions Limits on use

rolyl

tfrfas

oaf

ol

ep uopcrl

g it

n

1. Can’t be applied indoors,nor can it be used where itmay contaminate food,feed, drinking water, orirrigation water.

2. Can’t be applied to woodintended for use ininteriors, except for thosesupport structures that arein contact with the soil inbarns, stables, and similarsites, and that are subject todecay or insect infestation.Two coats of a sealer mustbe applied to such supportstructures.

1. Can’t be applied indoors,nor can it be used where itmay contaminate food,feed, drinking water, orirrigation water.

2. Can’t be applied to woodintended for use indoors,except for millwork withoutdoor surfaces, or forsupport structures that arein contact with the soil inbarns, stables, and similarsites, and that are subject todecay or insect infestation.In these instances, a sealermust be applied to thewood.

3. It’s prohibited to applypentachlorophenol to logsused in the construction oflog homes.

Creosote

Pentac 1. When you empty or mixprilled, powdered, orflaked formulations ofthis chemical, you mustuse a closed system.

2. When you use the spraymethod of application,you must operate thespray apparatus tominimize visible mist,and the apparatus mustbe free of leaks. Whenyou observe spray mistin the work zone,workers must wearapproved respirators,goggles, and clothingimpervious to thepreservative formula-tion (including overalls,jacket, gloves, boots,and head covering).

1. Toxic to fungi andinsects.

2. Can be dissolvedin oils having awide range ofviscosity, vaporpressure, andcolor.

3. Low solubility.4. Can be glued,

depending ondiluent or carrier.

5. Easy to handle anduse.

1. Can leaveunpaintabsurface, don carrier

2. Provides swhat less tion than

3. Not suitabuse in homother livin

4. Toxic anding to plananimals, apeople.

hlorophenol

Restricted-use pesticides creosote, pentachlorophenol,

Advantages Disadvant

1. Toxic to fungi,insects, andmarine borers.

2. Insoluble in water.3. Ease of handling

and application.

1. Dark colo2. Strong od3. Leaves oi

unpaintabsurface.

4. Tendencyor exude wood sur

5. Can’t be uhomes orliving arebecause ofumes.

cause damage tothe liver, kidneys,and nervoussystem.

ily,e

endingsed.me-rotec-eosote.e fores or areas.

rritat-s,d

1. Irritating to eyes,skin, and respira-tory tract.

2. Ingestion orexcessive dermalor inhalationexposure can leadto fever, headache,weakness, dizzi-ness, nausea, andprofuse sweating.

3. Prolonged highexposure levelscan lead to acne-like skin conditionor other skindisorders; it may

1. Considered ateratogen becauseit causes birthdefects in labora-tory animals.

2. A dioxin contami-nant in penta hasbeen shown tocause cancer inlaboratoryanimals, althoughit’s not the mosttoxic of thedioxins.

nd inorganic arsenicals: advantages, disadvantages, toxic effects (ac

Toxic effectsges Acute Chronic S

.r.,e

o bleedomce.ed intherstoxic

1. Skin irritation,burns, ordermatitis.

2. Vapors irritating toeyes and respira-tory tract.

3. Ingestion cancause nausea andabdominaldistress.

1. Laboratory animalstudies indicatethat it is a carcino-gen (cancer-causing agent).

2. Has been asso-ciated with skincancer in someoccupationallyexposed workers.

3. Bacteria andlaboratory animalstudies indicatethat it is a mutagen(causes genedefects).

7

Table 1.—Re rsenicals: advantages, disadvantages, toxic effects (acute and chronic), special precautions, and limits on use(continued).

Toxic effectsPesticide cute Chronic Special precautions Limits on use

Inorganic ar Exposure to highconcentrations cancause nausea,headache, diarrhea,and abdominalpain (if ingested);extreme symptomscan progress todizziness, musclespasms, delirium,and convulsions.Prolonged expo-sure can producepersistent head-aches, abdominaldistress, salivation,

,ra-

d

1. Bacteria andlaboratory animalstudies indicatethat it causesgenetic defects.

2. Shown to beassociated withcancer in peoplewho either drinkwater or breatheair contaminatedwith arsenic.

1. If the level of ambientarsenic in the work zoneis unknown, or if thelevel exceeds 10 micro-grams per cubic meterof air averaged over an8-hour work day, allexposed workers will berequired to wearapproved respirators.

2. Processes used to applyinorganic arsenicalformulations shall leaveno visible surfacedeposits on the wood.Small, isolated, orinfrequent spots ofchemical on otherwiseclean wood shall beallowed.

low-grade feverand upper respitory irritation.

3. Long-term, highexposure cancause liverdamage, loss ofhair and finger-nails, anemia, anskin disorders.

stricted-use pesticides creosote, pentachlorophenol, and inorganic a

Advantages Disadvantages A

senicals 1. Toxic to fungi,insects, and mostmarine borers.

2. Produces no smellor vapors.

3. Suitable for useindoors.

4. Suitable for usenear growingplants.

5. Treated surfacecan be painted.

1. Unless re-driedafter treatment,wood is subject towarping andcracking.

2. Doesn’t protectwood fromexcessiveweathering.

1.

2.

EPA’s decision to classifycreosote, pentachlorophenol, andinorganic arsenicals as “RestrictedUse” pesticides was based onpotential human health hazardsassociated with long-term, low-level exposure or chronic toxicity.

Table 1 lists the toxicity effects—acute and chronic—of the three“Restricted Use” preservatives.

Protecting the applicatorAnyone working with wood

preservatives will be exposed tothese chemicals to some extent, butthe exposure can be minimized byfollowing the directions on thepreservative label and developinggood work habits.

Personal hygieneBasic, commonsense hygiene

rules can significantly reduce the

8

risks of chronic exposure to woodpreservatives. For example:• Wash hands often, especially

before using the restroom,smoking, or eating.

• Don’t eat, drink, or smoke in thework area—these activities willincrease the amount of preserva-tive absorbed into the body.

• Remove gloves to handle paper-work, phones, or equipment thatothers may handle with unpro-tected hands.

• Launder protective clothing atthe work site. If work clothesmust be laundered at home,wash them separately from otherlaundry.

Protective equipment and clothingThe pesticide label will specify

the type of protective equipment

and clothing that should be wornwhen working with wood preserva-tives. Where skin contact isexpected (for example, handlingfreshly treated wood or manuallyopening pressure-treatment cylin-ders), the label will specify the useof impermeable gloves.

Leather may protect hands fromslivers, but leather gloves don’tprotect the wearer from woodpreservatives! In fact, preservative-contaminated leather glovesdefinitely will contribute to theamount of preservative absorbedinto the body.

Individuals who enter pressure-treatment cylinders or other relatedequipment contaminated withwood-treatment solutions mustwear protective equipment thatdoes not allow the wood treatmentsolution to penetrate. This includesoveralls, jacket, gloves, boots, andrespirator.

First AidSince accidents do happen, first aid informa-

tion on the chemical(s) in use must be readilyavailable. The product label provides basic firstaid directions, as do Material Safety Data Sheetssupplied by the chemical manufacturers (seepage 9). Take the following steps if accidentalexposure to wood preservatives occurs:• In cases of skin contact, first remove con-

taminated clothing in contact with the skinand immediately wash the affected skin areaswith mild soap and water. Don’t irritate theskin with vigorous scrubbing. If you noticeskin inflammation later, consult a physician.

• In cases of eye exposure, immediately flush theeyes with running water. Lift the upper and lowereyelids for complete irrigation and continue for15 minutes; then see a physician.

• If accidental inhalation occurs, move the victim tofresh air and apply artificial respiration as needed.Get medical help immediately!

• Accidental ingestion of any wood preservativerequires immediate medical attention. If creosoteor penta was swallowed—and if the person isconscious—give one or two glasses of water, inducevomiting, and then administer two tablespoons of“USP Drug Grade” activated charcoal in water.Never attempt to administer anything orally or inducevomiting to an unaware or unconscious person.

• If an arsenical chemical has been swallowed, thevictim should drink large quantities of water ormilk. Get professional medical help immediately!

• Acute toxicity symptoms for all three preservativesusually are noticed soon after exposure and usuallyare treatable if first aid is administered quickly.

Respirators must be approved bythe Mine Safety and Health Admin-istration and the National Institutefor Occupational Safety and Health(MSHA/NIOSH), and they must beproperly fitted and maintained.

Special precautionsSee Table 1 for special precau-

tions on pentachlorophenol andarsenicals.

Limits on useEPA regulations on wood

preservatives include some limita-tions on treating wood intended forcertain uses, and on certain uses oftreated wood. Not all the limita-tions are the responsibility ofcommercial treaters, but all woodtreaters should understand theselimitations. Table 1 includes asummary of these use limitations.

Material Safety DataSheets (MSDS)

Material Safety Data Sheets areavailable from the manufacturersand distributors of the woodpreservatives they sell. EachMSDS provides information aboutthe toxicity, first aid, protectiveequipment, storage and handlingprecautions, disposal procedures,transportation, etc. for a specificproduct.

All wood treaters should have anMSDS on file for each differentformulation they use. In Washingtonand Oregon, the Right to Know Lawrequires this.

Voluntary ConsumerAwareness Program

The treated wood industry hasdeveloped a voluntary ConsumerAwareness Program (CAP)designed to inform the consumerabout the proper uses of treatedwood and the proper precautionarymeasures to take when using suchwood. The treated wood industry is

committed to the implementation ofthe CAP and the education of theconsuming public.

The treated wood industry hasdeveloped a model ConsumerInformation Sheet (CIS) containinguse site precautions and safeworking practices for each of thethree types of preservatives. TheCIS serves as the main vehicle forconveying information abouttreated wood to consumers.

The focus of the CAP is to ensurethe dissemination of the CIS at thetime of sale or delivery to endusers. Wood treaters assumeprimary responsibility for dissemi-nation of the CIS to consumers.

The following wording appearson the Consumer InformationSheets for the three “RestrictedUse” chemicals:

Wood pressure-treatedwith an inorganic arsenical

“Consumer information—Thiswood has been preserved bypressure treatment with anEPA-registered pesticide containinginorganic arsenic to protect it frominsect attack and decay. Woodtreated with inorganic arsenicshould be used only where suchprotection is important.

“Inorganic arsenic penetratesdeeply into and remains in thepressure-treated wood for a longtime. Exposure to inorganicarsenic may present certain haz-ards: Therefore, the followingprecautions should be taken whenhandling the treated wood, indetermining where to use thewood, and in disposing of thetreated wood.

“Use site precautions—Woodpressure-treated with waterbornearsenical preservatives may be usedinside residences as long as allsawdust and construction debrisare cleaned up and disposed ofafter construction. Do not use

treated wood under circumstanceswhere preservatives may become acomponent of food or animal feedin such sites as structures orcontainers used to store silage orfood.

“Don’t use treated wood forcutting boards or countertops. Onlytreated wood that is visibly cleanand free of surface residue shouldbe used in patios, decks, andwalkways.

“Don’t use treated wood forconstruction of those portions ofbeehives that may come intocontact with the honey. Treatedwood should not be used where itmay come into direct or indirectcontact with public drinking water,except for uses involving incidentalcontact such as docks and bridges.

“Handling precautions—Disposeof treated wood by ordinary trashcollections or burial. Treated woodshould not be burned in open fires,wood stoves, fireplaces, or residen-tial boilers because toxic chemicalsmay be produced as part of thesmoke and ashes. Treated woodfrom commercial or industrial use(for example, construction sites)may be burned only in commercialor industrial incinerators or boilersin accordance with State andFederal regulations.

“Avoid frequent or prolongedinhalation of sawdust from treatedwood. When sawing and machin-ing treated wood, wear a dustmask. Whenever possible, theseoperations should be performedoutdoors to avoid indoor accumula-tions of airborne sawdust fromtreated wood. When power-sawingor machining, wear goggles toprotect eyes. After working withthe wood, and before eating,drinking, or using tobacco prod-ucts, wash exposed body areasthoroughly. If preservatives orsawdust accumulate on clothes,launder before reuse.”

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Wood pressure-treatedwith creosote

“Consumer information—Thiswood has been preserved bypressure treatment with an EPA-registered pesticide containingcreosote to protect it from insectattack and decay. Wood treatedwith creosote should be used onlywhere such protection is important.

“Creosote penetrates deeply intoand remains in the pressure-treatedwood for a long time. Exposure tocreosote may present certainhazards; therefore, the followingprecautions should be taken bothwhen handling treated wood and indetermining where to use thetreated wood.

“Use site precautions—Woodtreated with creosote should not beused where it will be in frequent orprolonged contact with bare skin(for example, chairs and otheroutdoor furniture) unless aneffective sealer has been applied.

“Creosote-treated wood shouldnot be used in residential interiors.Creosote-treated wood in interiorsof industrial buildings should beused only for components that arein ground contact and are subject todecay or insect infestation, and forwood block flooring. For such uses,two coats of an appropriate sealermust be applied. Sealers may beapplied at the installation site.

“Wood treated with creosoteshould not be used in the interiorsof farm buildings where the woodmay be in direct contact withdomestic animals or livestock thatmay crib (bite) or lick the wood. Ininteriors of farm buildings, wheredomestic animals or livestock areunlikely to crib or lick the wood,creosote-treated wood may be usedfor building components that are inground contact and are subject todecay or insect infestation; how-ever, two coats of an effective sealermust be applied. Sealers may beapplied at the installation site. Coal

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tar pitch and coal tar pitch emulsionare effective sealers for creosote-treated woodblock flooring.Urethane, epoxy, and shellac areacceptable sealers for all creosote-treated wood.

“Don’t use treated wood forfallowing or brooding facilities.Don’t use treated wood undercircumstances where the preserva-tive may become a component offood or animal feed in structures orcontainers used for storing silage orfood. Don’t use treated wood forcutting-boards or countertops. Onlytreated wood that’s visibly cleanand free of surface residues shouldbe used for patios, decks, or walk-ways. Don’t use treated wood forconstruction of those portions ofbeehives that may come in contactwith the honey.

“Creosote-treated wood shouldnot be used where it may come intodirect or indirect contact withpublic drinking water or withdrinking water for domesticanimals or livestock, except for usesinvolving incidental contact such asdocks and bridges.

“Handling precautions—Disposeof treated wood by ordinary trashcollection or burial. Treated woodshould not be burned in open fires,wood stoves, fireplaces, or residen-tial boilers because toxic chemicalsmay be produced as part of thesmoke and ashes. Treated woodfrom commercial or industrial use(for example, construction sites)may be burned only in commercialor industrial incinerators or boilersin accordance with State andFederal regulations.

“Avoid frequent or prolongedinhalation of sawdust from treatedwood. When sawing and machin-ing treated wood, wear a dustmask. Whenever possible, theseoperations should be performedoutdoors to avoid indoor accumula-tions of airborne sawdust fromtreated wood. When power-sawing

or machining, wear goggles toprotect eyes.

“Avoid frequent or prolongedskin contact with creosote-treatedwood. When you handle the treatedwood, wear long-sleeved shirts andlong pants. Use gloves that areimpervious to the preservative (forexample, gloves that are vinyl-coated). When you’re power-sawing or machining, wear gogglesto protect your eyes. After workingwith the wood, and before eating,drinking, or using tobacco prod-ucts, wash exposed body areasthoroughly. If preservatives orsawdust accumulate on clothes,launder before reuse.”

Wood pressure-treatedwith pentachlorophenol

“Consumer information—Thiswood has been preserved bypressure treatment with an EPA-registered pesticide containingpentachlorophenol to protect itfrom insect attack and decay. Woodtreated with pentachlorophenolshould be used only where suchprotection is important.

“Pentachlorophenol penetratesdeeply into and remains in thepressure-treated wood for a longtime. Exposure to pentachlorophe-nol may present certain hazards;therefore, the following precautionsshould be taken both when han-dling treated wood and in deter-mining where to use the treatedwood.

“Use site precautions—Logstreated with pentachlorophenol arenot to be used for log homes. Woodtreated with pentachlorophenolshould not be used where it will bein frequent or prolonged contactwith bare skin (for example, chairsand other outdoor furniture), unlessan effective sealer has been applied.

“Pentachlorophenol-treatedwood is not to be used in residen-tial, industrial, or commercialinteriors except for laminated

beams or building components thatare in ground contact and aresubject to decay or insect infesta-tions and where two coats of anappropriate sealer are applied.Sealers may be applied at theinstallation site.

“Wood treated with pentachlo-rophenol is not to be used in theinteriors of farm buildings wherethe wood may be in direct contactwith domestic animals or livestockthat may crib (bite) or lick thewood. In interiors of farm build-ings, where domestic animals orlivestock are unlikely to crib or lickthe wood, pentachlorophenol-treated wood may be used forbuilding components that are inground contact and are subject todecay or insect infestation; how-ever, two coats of an effective sealermust be applied. Sealers may beapplied at the installation site.Urethane, shellac, latex epoxyenamel, and varnish are acceptablesealers for pentachlorophenol-treated wood.

“Don’t use pentachlorophenol-treated wood for fallowing orbrooding facilities. Don’t usetreated wood under circumstanceswhere the preservative may becomea component of food or animal feedin structures or containers used forstoring silage or food. Don’t usetreated wood for cutting boards orcountertops. Only treated woodthat’s visibly clean and free ofsurface residues should be used forpatios, decks, or walkways. Don’tuse treated wood for construc-tion of those portions ofbeehives that may comeinto contact with the honey.

“Pentachlorophenol-treatedwood must not be usedwhere it may come intodirect or indirect contactwith public drinkingwater or with drinkingwater for domestic

animals or livestock, except for usesinvolving incidental contact such asdocks and bridges.

“Handling precautions—Disposeof treated wood by ordinary trashcollection or burial. Treated woodshould not be burned in open fires,wood stoves, fireplaces, or residen-tial boilers because toxic chemicalsmay be produced as part of thesmoke and ashes. Treated woodfrom commercial or industrial use(for example, construction sites)may be burned only in commercialor industrial incinerators or boilersrated at 20 million BTU/hour orgreater heat input or its equivalentin accordance with State andFederal regulations.

“Avoid frequent or prolongedinhalation of sawdust from treatedwood. When sawing and machin-ing treated wood, wear a dustmask. Whenever possible, theseoperations should be performedoutdoors to avoid indoor accumula-tions of airborne sawdust fromtreated wood. When you’re power-sawing or machining, wear gogglesto protect your eyes.

“Avoid frequent or prolongedskin contact with pentachloro-phenol-treated wood. Whenhandling the treated wood, wearlong-sleeved shirts and long pants.Use gloves that are impervious tothe preservative (for example,gloves that are vinyl-coated). Whenyou’re power-sawing or machining,wear goggles to protect your eyes.

After working with thewood, and beforeeating, drinking, orusing tobacco prod-ucts, wash exposed

body areasthoroughly. Ifoily preserva-tives or saw-

dust accumulate onclothes, launderbefore reuse.”

Protecting theenvironment

Waste disposalWastes from preservative-

treating operations can kill plantlife and harm aquatic life if they’reallowed to enter waterways. Oilsand organic solids damage aquaticlife by reducing oxygen supplies.

Some treating plants dischargetheir wastes into approved munici-pal sewer systems for processingalong with municipal wastes. Manyplants use closed chemical andwastewater recovery systems tocontain wastes that could beharmful. Recovered solutions maybe used again. If they are contami-nated, they can be filtered toremove solid wastes. Liquid wastematerials may be diverted tosettling ponds.

Door sumps should be usedunder pressure-chamber doors andunder hard-surfaced drainageareas. Any excess chemicals thatdrip or are rinsed from freshlytreated material are thus channeledinto the waste or recovery system. Italso is important to contain therunoff from areas where toxicchemicals are used to protect storedlogs, poles, or lumber beforeprocessing or during seasoning.

Remember to read the preserva-tive label carefully for disposalinformation. The U.S. Environmen-tal Protection Agency requirestreatment facilities to meet certaindisposal standards. EPA alsorequires that treatment plantsobtain permits for dischargingexcess chemicals. Compliance withthe label and EPA regulationsshould assure proper environmen-tal protection.

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Storage and disposalof containers

Packaged chemicals should bestored in a dry, well-ventilated,securely locked area. Keep them inwell-sealed containers wheneverpossible. Protect liquid storageagainst tank rupture. Whereverspills, leaks, or flooding couldoccur, be sure that runoff will draininto a recovery or disposal system.

Protect concrete vats againstfreezing, cracking, or spillage.Thoroughly rinse containers andempty them into storage or treatingtanks before disposal. Dispose ofthe containers at an approvedlandfill or by other approvedmeans. Be particularly careful notto contaminate streams or ground-water.

Be sure to read and follow thelabel requirements and the MaterialSafety Data Sheet (MSDS) for eachpreservative. If you’re in doubtabout how to safely store a productor dispose of the empty containers,contact the chemical supplier oryour State agency that regulatesstorage and container disposal.

SpillsCorrect cleanup procedures

depend on the chemical involved.Treating-plant personnel shouldknow what chemicals are beingstored and used, and they shouldhave an advance plan for handlingspills. All workers who might beinvolved should know what help isavailable and who to notify in caseof a major spill.

Environmental exposureIt’s not only people who can

suffer from the careless use ordisposal of wood preservatives—your community’s environmentalso may suffer. Creosote, pen-tachlorophenol, and inorganicarsenicals are toxic. They must betoxic to kill or repel the fungi,

12

insects, and marine borers thatdestroy wood. Unfortunately, thesechemicals are not selective; they canharm nontarget organisms.

Contaminated runoff can pollutelakes, streams, and wetlands,thereby damaging habitat for fishand wildlife. Specifics vary, butpenta, creosote, and inorganicarsenicals are all toxic to fish andother wildlife.

PentachlorophenolThis chemical is not uncommon

in the aquatic environment and isextremely toxic to fish. Exposure topenta concentrations in the parts-per-billion range can cause deathwithin minutes for many species ofsalmon and trout.

Circumstantial evidence, includ-ing the identification of penta inrainwater, indicates that pentaoccasionally may be present inambient air. Low levels of thiscompound have been detected inboth wastewater and surface water.

While the source of these resi-dues often is unclear, it’s beensuggested that, in addition to directcontamination of water by penta,degradation of other organiccompounds or chlorination of watermay result in the chemical produc-tion of penta.

Penta is moderately persistent inthe aquatic environment. It wasreportedly detected in lake waterand fish 6 months after an acciden-tal spill.

Penta also is moderately persis-tent in the soil. Persistence report-edly ranges from 21 days to 5 years.Under most conditions, pentaseldom will persist in the soil forperiods exceeding 9 monthsbecause many soil microorganismshave been identified that arecapable of degrading penta.

Since the major uses of pentadon’t involve applying it to the soil,the likeliest source of soil contami-nation is the leaching or bleeding of

the preservative from treated wood.This may result in low levels ofpenta contamination in the immedi-ate vicinity of the treated wood.

Significant accumulation ofpenta in plants and mammals is notlikely to occur because penta is nottranslocated in plants, and it’srapidly eliminated by mammalsfollowing exposure.

ArsenicalsNo problems have ever been

found in the literature as to theeffects of arsenical wood preserva-tives on the environment. Arsenate,the form present in aerobic soils, isbound tightly to the soil compo-nents and becomes unavailable forplant uptake or leaching.

CreosoteThere are no recorded reports of

wild or domestic animals beinginjured by creosote. The amount ofcreosote that enters the environ-ment as a liquid is relatively small.The fate of creosote in the environ-ment isn’t known, but most of itscomponents are quickly biode-graded.

Groundwater pollutionUse of wood preservatives over

the years has been cited as a sourceof pollution in surface and ground-water in many parts of this country.Some of this problem has comefrom obvious sources such as spillsor illegal discharge of chemicalsinto ditches, storm drains, orsewers. Another less obvioussource is the uncontained drippingsfrom freshly treated wood.

Although preservative pollutionof surface water is more obviousand can be a serious problem,groundwater pollution potentiallyis a very serious problem. In manycommunities, groundwater is theonly source of drinking water.When groundwater becomescontaminated with any chemical,

cleanup—where possible—is verydifficult and costly. Testing hasdocumented contamination inpublic and private wells at levelsexceeding health advisories.

Groundwater typically isaffected by contamination of theoverlying soil. Such contaminationusually is the result of applyingpreservatives to soil, spills, over-flow from tanks or holding ponds,and improper disposal.

To reduce the chance of environ-mental contamination, properprotective measures must be anintegral part of all your woodpreservation operations.

DefinitionsDefinitions for some of the terms

used in the manual were takenmainly from Wood as an EngineeringMaterial, Wood Handbook, USDAAgricultural Handbook 72, Revised1974.Cellulose. The carbohydrate that is

the principal constituent of woodand forms the framework of thewood cells.

Check. A lengthwise separation ofthe wood that usually extendsacross the rings of annual growthand commonly results fromstresses set up in wood duringseasoning.

Decay. The decomposition of woodsubstance by fungi.Incipient decay. The early stage ofdecay that has not proceeded farenough to soften or otherwiseperceptibly impair hardness ofthe wood. It usually is accompa-nied by a slight discoloration orbleaching of the wood.Advanced (or typical) decay. Theolder stage of decay in which thedestruction is readily recognizedbecause the wood has becomepunky, soft and spongy, stringy,ringshaked, pitted, or crumbly.Decided discoloration or bleach-ing of the rotted wood often isapparent.

Dry rot. A term loosely applied toany dry, crumbly rot, butespecially to that which, when inan advanced stage, permits thewood to be crushed easily to adry powder. The term actually isa misnomer for any decay, sinceall fungi require considerablemoisture for growth.

Green. Freshly sawn or undriedwood that still contains tree sap.Wood that has become com-pletely wet after immersion inwater would not be consideredgreen, but may be said to be inthe “green condition.“

Hardwoods. Generally one of thebotanical groups of trees thathave broad leaves in contrast tothe conifers or softwoods. Theterm has no reference to theactual hardness of the wood.

Heartwood. The wood extendingfrom the pith to the sapwood, thecells of which no longer partici-pate in the life processes of thetree. Heartwood may containphenolic compounds, gums,resins, and other materials thatusually make it darker and moredecay-resistant than sapwood.

Kiln. A chamber having controlledairflow, temperature, and relativehumidity for drying lumber,veneer, and other wood products.

Lignin. The second most abundantconstituent of wood, locatedprincipally in the secondary walland the middle lamella, which isthe thin cementing layer betweenwood cells. Chemically, it’s anirregular polymer of substitutedpropylphenol groups (so nosimple chemical formula can bewritten for it).

Millwork. Planed and patternedlumber for finish work in build-ings, including items such assash, doors, cornices, panelwork,and other items of interior orexterior trim. Doesn’t includeflooring, ceiling, or siding.

Moisture content. The amount ofwater contained in wood,usually expressed as a percent-age of the weight of the ovendrywood.

Ovendry wood. Wood dried to arelatively constant weight in aventilated oven at 101 to 105°C.

Preservative. Any substance that,for a reasonable length of time,is effective in preventing thedevelopment and action ofwood-rotting fungi, borers ofvarious kinds, and harmfulinsects that deteriorate wood.

Sapwood. The wood of pale colornear the outside of the log andjust under the bark of a tree.Under most conditions, thesapwood is more susceptible todecay than heartwood, andusually it is more receptive toimpregnation with preservativesand fire retardants.

Seasoning. Removing moisturefrom green wood to improve itsserviceability.Air-dried. Dried by exposure toair in a yard or shed, withoutartificial heat.Kiln-dried. Dried in a kiln withthe use of artificial heat.

Soft rot. A special type of decaydeveloping under very wetconditions (as in cooling towersand boat timbers) in the outerwood layers, caused by cellulose-destroying microfungi that attackthe secondary cell walls and notthe intercellular layer.

Softwoods. Generally, one of thebotanical groups of trees that, inmost cases, have needlelike orscalelike leaves: the conifers, alsothe wood produced by suchtrees. The term has no referenceto the actual hardness of thewood.

Weathering. The mechanical orchemical disintegration anddiscoloration of the surface ofwood caused by exposure tolight, the action of dust and sand

13

carried by winds, and thealternate shrinking and swellingof the surface fibers with thecontinual variation in tempera-ture and moisture contentbrought by changes in theweather. Weathering doesn’tinclude decay.

White rot. In wood, any decay orrot that attacks both the celluloseand lignin and produces agenerally whitish residue thatmay be spongy or stringy rot, oroccur as pocket rot.

For further readingIf you would like additional

copies of EM 8403, Wood Preserva-tion and Wood Products TreatmentTraining Manual, send $1.50 percopy to:

Publication OrdersExtension & Station CommunicationsOregon State University422 Kerr AdministrationCorvallis, OR 97331-2119Fax: 541-737-0817

We offer discounts on orders of100 or more copies of a single title.Please call 541-737-2513 for pricequotes.

You can access our Publicationsand Videos catalog and many ofour publications via the WorldWide Web at eesc.orst.edu

Other publicationsThe publications listed below are

intended to provide basic informa-tion essential to safe handling ofpesticides and to prepare treatersfor certification. Changes in pesti-cide registration and use require

This publication was producsion work is a cooperative pr

Oregon State University Extecolor, religion, sex, sexual orienstatus—as required by Title V504 of the Rehabilitation Act

Published September 1989. R

continuing study to keep up todate. Proceedings, standards, andother publications of the AmericanWood Preservers Associationprovide current information forwood preservers. Other tradepublications also will prove helpful.

Fuller, B., et al., The Analysis ofExisting Wood Preserving Tech-niques and Possible Alternatives,Metrek Division/The MitreCorporation, developed undercontract with the U.S. Environ-mental Protection Agency, June1977.

Graham, Robert D., and Guy C.Helsing, Wood Pole MaintenanceManual: Inspection and Supplemen-tal Treatment of Douglas-fir andWestern Redcedar Poles, OregonState University, FRL ResearchBulletin 24, February 1979.

Gjovik, Lee Jr., and Roy B. Baechler,Selection, Production, Procurementand Use of Preservative-treatedWood, Supplementing FederalSpecification TT-W-571, USDAForest Service, General TechnicalReport FPL-15, 1977.

Handling Precautions for Penta andSantobrite, Technical BulletinNo. O/PS-3, Monsanto Co.,Organic Chemical Division,St. Louis, MO 63166.

Hunt, George M., and George A.Garratt, Wood Preservation,3rd edition (New York: McGrawHill, 1953).

Koch, Peter, Utilization of the South-ern Pines, USDA AgricultureHandbook No. 420, August 1972.Provides information onwood-destroying organisms andthe treating process.

ed and distributed in furtherance of the Acts of Cogram of Oregon State University, the U.S. Depa

nsion Service offers educational programs, activitation, national origin, age, marital status, disability, I of the Civil Rights Act of 1964, Title IX of the E

of 1973. Oregon State University Extension Servi

eprinted October 1998.

Konasewich, D.E., et al.,Chlorophenate Wood Protection,British Columbia Ministry ofEnvironment, Wood ProtectionTask Force, 1983. 90 pp.

Maclean, J.D., Preservative Treatmentof Wood by Pressure Methods,USDA Agriculture HandbookNo. 40, December 1952.Reprinted with correctionsSeptember 1960.

Morrel, Jeffrey, Guy C. Helsing, andRobert D. Graham, Marine WoodMaintenance Manual: A Guide forProper Use of Douglas-fir in MarineExposures, Oregon State Univer-sity, FRL Research Bulletin 48,October 1984.

Nicholas, Darrel D., editor, withassistance of Wesley E. Loos,Wood Deterioration and Its Preven-tion by Preservative Treatment, twovolumes (Syracuse, NY: SyracuseUniversity Press, 1973).

Safe Handling Guide to SapstainControl Chemicals, Western WoodProducts Assn., 1500 Yeon Bldg.,Portland, OR, 1982. 14 pp.

Stalker, Ian, and Milton Applefield,The Preservation of Wood, Univer-sity of Georgia, ExtensionEntomology (Athens, 1986). Acorrespondence course for woodtreaters. 150 pp.

Wood as an Engineering Material,chapters 17-19 of USDA Agricul-ture Handbook No. 72, revised1974.

Wood Preservation: ApplicatorsManual, Western Wood ProductsAssn., 1500 Yeon Bldg., Portland,OR.

ongress of May 8 and June 30, 1914. Exten-rtment of Agriculture, and Oregon counties.

ties, and materials—without regard to race,and disabled veteran or Vietnam-era veteranducation Amendments of 1972, and Sectionce is an Equal Opportunity Employer.