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United States
Department of
Agriculture SELECTION AND USE

Forest Service
Technology & OF PRESERVATIVE
TREATED WOOD
Development
Program
Forest Product

IN FOREST SERVICE
Laboratory

2300—Recreation
May 1995

RECREATIONAL
9523 1203—SDTDC

STRUCTURESS
SELECTION AND USE
OF PRESERVATIVE
TREATED WOOD
IN FOREST SERVICE
RECREATIONAL
STRUCTURES

By Stan T. LeBow
Forest Products Technologist,
Forest Products Laboratory
Madison, Wisconsin 53705-2398

and

William J. Makel
Program Leader, Recreation
San Dimas Technology & Development Program
San Dimas, California 91773-3198

TEO1A35
Technical Services

May 1995

The Forest Service, U.S. Department of Agriculture has developed this information for
the guidance of its employees, its contractors, and its cooperating Federal and State
agencies, and is not responsible for the interpretation or use of this informaltion by
anyone except ist own employees. the use of trade, firm, or corporation names in this
publication is for the inforation and convienience of the reader and does not constitute
an endorsement by the U.S. Department of Agriculture of any product or service to the
exclusion of others that may be suitable.

The United States Department of Agriculture (USDA) forest Service is a diverse
organixation committed toequal opportunity in employmentand programdelivery. USDA
prohibits discrimination on the basis of race, color, national origin, sex, religion, age,
disability, political affiliation and familial status. Persons believing they have been
discriminated against should contact the Secretary, U.S. Department of Agriclulture,
Washington, DC 20250, or call 202-720-7327 (voice), or 202-720-1127 (TDD).
TABLE OF CONTENTS

BACKGROUND ...................................................................................................................... 1

TYPES OF WOOD PRESERVATIVES .......................................................................................... 3

Oil-Type ................................................................................................................................ 3

Creosote ................................................................................................................... 3

Pentachlorophenol ..................................................................................................................... 4

Copper naphthenate .................................................................................................................. 4

Waterborne ................................................................................................................................. 4

Chromated copper arsenate (CCA) ......................................................................................... 4

Ammoniacal copper zinc arsenate (ACZA) .............................................................................. 5

Ammoniacal copper arsenate (ACA) ........................................................................................ 5

Alkaline copper quaternary (ACQ) compounds .......................................................................... 5

Ammoniacal copper citrate (CC ................................................................................................ 5

Copper bis (dimethyldithocarbamate) (CDDC) ............................................................................. 6

Borates ...................................................................................................................................... 6

CURRENT KNOWLEDGE OF LEACHING AND EFFECTS ON THE

ENVIRONMENT ...................................................................................................................... 6

RECOMMENDED GUIDELINES ............................................................................................. 8

Selection of a Wood Preservative .................................................................................. 8

Wood Species ........................................................................................................................... 8

Type of Structures ................................................................................................................... 8

Cost and Availability ................................................................................................................. 8

Ecosystems Sensitivities ......................................................................................................... 8

Purchase of a Treated Wood Product ...................................................................... 9

Treatment .................................................................................................................................. 9

Fixation and Surface Cleanliness .......................................................................................... 10

Use of a Treated Wood Product ..................................................................................... 11

Site Selection ............................................................................................................................ 11

Construction and Handling ..................................................................................................... 11

i
FIGURES
Figure 1. Glu-lam trail bridge ....................................................................................................... 3

Figure 2. Bridge walkway ............................................................................................................. 7

Figure 3. Boardwalk in sensitive habitat ..................................................................................... 8

Figure 4. Stamp of accredited inspection agency ...................................................................... 9

Figure5. Worksite ...................................................................................................................... 11

BACKGROUND

Preservative treated wood is an economical, durable
and aesthetically pleasing building material, and
is a natural choice for many construction projects
in the National Forests. The purpose of treating
wood with preservatives is to protect the wood
from wood-destroying fungi and insects. Treating
wood with preservative chemicals can increase
the service life of wood by a factor of 5 times or
more. Wood treated with commonly used wood
preservatives can last 40 years or more in service.

Many field applications place treated wood in
sensitive ecosystems where contamination by
significant amounts of preservative compounds
could negatively affect the environment. There is
increasing pressure to reduce, restrict, or eliminate
the use of wood preservatives for fear toxic components
may Teach from the treated wood. This article is
intended to give the reader an overview of preservative
systems, aid in understanding the level of risk and
status of the science, and provide some guidelines
for using the products.

TYPES OF WOOD PRESERVATIVES the touch, and sometimes have a noticeable
Wood preservatives have been used for over odor. However, using the oil or solvent as
a hundred years. They are broadly classified carriers makes the wood less susceptible to
as either waterborne or oil-type, based on cracksand checking and therefore moresuitable
the chemical composition of the preservative for treatment of glu-lam stringers for bridges
and the carrier used during the treating process. where cracks could alter the structural integrity.
(See figure 1 ) .
Oil-Type
The common oil-type preservatives are creosote, Creosote
pentachlorophenol, and copper naphthenate. Creosote is a chemically complex mixture of
Oil-type preservatives, such as creosote and organic molecules derived from coal tar produced
pentachlorophenol solutions have largely been by carbonization of coal. The active ingredients
confined to uses that do not involve frequent are the polycyclic aromatic hydrocarbons (PAH's)
human contact. The exception is copper which are toxic to fungi, insects, and marine
napthenate, a more recent and less widely borers if present in sufficient concentrations.
used oil-type wood preservative. OiI-type It has been widely used for bridge timbers
preservatives may be visually oily, or oily to railroad ties, utility poles, and pilings in aquatic

Figure 1. Glu-lam trail bridge.

3
environments. Creosote remains in the wood insects, but is not recommended for use in
due to its Iow volatility and low solubility in marine applications. Like pentachIorophenoI,
water, but does have a tendency to “ooze or its properties are influenced by the type of
bleed” from the wood, especially in hot weather carrier solvent used. The most commonly
or direct sun. It has a dark brown/black color used carrier solvents are fuel oil and mineral
with an oily surface and strong odor. It is not spirits. Although copper naphthenate has little
recommended for use in recreational areas odor, the odor of oil or solvent may make this
where it is subject to frequent public contact. treatment less acceptable in some trail
Information on the availability of creosote applications. Color ranges from light green to
treated wood can be obtained by contacting dark brown depending on the treating process,
the appropriate trade association listed on the solvent, and the treating temperature.
the last page. Unlike creosote and pentachlorophenol, copper
naphthenate is not a restricted-use pesticide,
Pentachlorophenol and thus is widely used for field treatment of
Pentachlorophenol is a crystalline solid that cuts made during construction. For information
is typically dissolved in a petroleum solvent on availability of copper naphthenate treated
to form a five percent solution. This preservative wood see appropriate trade association listed
is effective against fungi and insects, but on the last page.
does not protect well against marine borers.
Pentachlorophenol is widely used for utility Waterborne
poles and crossarm applications, guardrail Chromated copper arsenate, ammoniacal copper
posts, and laminated bridge timber constructions. arsenate, ammoniacal copper zinc arsenate,
The properties of the treated wood depend ammoniacal copper citrate, alkaline copper
greatly on the type of solvent used. Light, quaternary compounds, and copper
volatile solvents produce a light brown color bis (dimethyldithocarbamate) are waterborne
and a relatively clean surface; heavier solvents preservatives which react with or precipitate
produce characteristics similar to those of in the wood substrate and become “fixed”
creosote treated wood. Pentachlorophenol (the preservative compounds in the solutions
is odorless, but the odor of the solvent may are fixed in the wood in an insoluble state.)
be detectable, especially in freshly treated Borates are another type of waterborne
wood. As with other oil-type preservatives, preservative; however, current borate
permanence in the wood results from low preservatives do not “fix” in the wood and are
water solubility and low volatility. Although readily leached if exposed to rain or wet soil.
pentachlorophenol treated wood is often used
in recreational structures, it is not recommended Chromated copper arsenate (CCA)
for hand-rails where it is subject to frequent CCA contains hexavalent chromium, copper,
public contact. Information on the availability and arsenic. The chromium is the fixation
of pentachlorophenol treated wood can be agent and reacts chemically with the copper
obtained by contacting the appropriate trade and arsenic fixing them in the wood. During
association listed on the last page. this process the chromium is reduced to the
trivalent state. Copper protects against fungi
Copper naphthenate andarsenic protects against insects andcopper
Copper naphthenate is a mixture of napthenic tolerant fungi. It is the most widely used
acids and copper salts dissolved in a petroleum wood preservative, favored for lumber treatment
solvent. It is affective against decay and because it is inexpensive, leaves a dry, paintable

4
surface, and binds to the wood to become Douglas fir heartwood (although incising is
relatively leach-resistant. However, it is difficult still recommended). ACQ-D uses an amine
to achieve adequate penetration with CCA solvent. It does not penetrate the wood as
when treating less porous woods such as the well as ACQ-B, but has a nicer surface
heartwood of Douglas fir. Color is alive green appearance. Both copper and quat protect
which weathers to driftwood gray. CCA treated against fungi. Neither type of ACQ contains
wood is readily available in all parts of the arsenic or chromium. AIthough ACQ formulations
continental United States. are newer preservatives with less time in
service than conventional preservatives, they
Ammoniacal copper zinc arsenate have been tested by accelerated testing methods
(ACZA) including soil block, soil bed exposure and
field stake tests. ACQ varies in color from
ACZA contains copper, zinc, and arsenic.
brown to deep green depending on wood
The ingredients are dissolved in a solution of
species, chemical retention and heartwood.
ammonia (NH3) in water. Ammonia is the
It will weather to a brown tone over time as
fixation agent which evaporates causing the
exposed to sunlight. For information on the
preservatives to precipitate in solid form within
availability of ACQ treated wood call Chemical
the wood structure. Copper and zinc protect
Specialities Inc., Harrisburg, NC 1-800-421
against fungi; and arsenic protects against
8661.
insects and copper tolerant fungi. Until recently
this was the only waterborne pressure treatment
available to penetrate Douglas fir and assure Ammoniacal copper citrate (CC)
compliance with American Wood Preservers CC contains copper oxide and citric acid
Association (AWPA) standards. Color is olive dissolved in a solution of ammonium, carbon
to bluish-green which weathers to driftwood dioxide, and water. As with other ammoniacal
gray. ACZA is a further refinement on the systems, this preservative is more effective
original formulation, ACA. For information on than CCA in achieving adequate penetration
the availability of this product call J.H. Baxter of difficult to treat species. Incising is
and Company, San Mateo, CA 1-415-573 recommended for treatment of Douglas fir.
3311. The copper protects against fungi and insects,
while the citric acid aids in the distribution of
Ammoniacal copper arsenate (ACA) the copper within the wood. Although CC is a
ACA contains copper and arsenic. It is similar new preservative with less time in service
to ACZA, except that it contains more arsenic than conventional preservatives, it has been
and no zinc. ACA has been replaced by ACZA tested with accelerated methods such as soil
in the United States, but is still used in Canada. blocks, field stakes, and pole stubs. This
Research indicates that ACZA is superior to preservative does not contain chromium or
ACA in leach-resistance and performance. arsenic. The appearance of the treated wood
varies from light green to dark brown. Due to
its recent development, this preservative may
Alkaline copper quaternary (ACQ) not be readily available in all areas of the
Compounds country. Information about the availability of
ACQ contains copper and quaternary ammonium this type of preservative treated wood can be
compounds (didecyldimethylammonium obtained by calling:
chlorides). Two types of ACQ are commercially
available. ACQ-B uses ammonia as a solvent, Osmose Wood Reserving, Griffin, GA
West Coast: 1-800-786-3325
which allows it to penetrate wood such as East Coast: 1-800-241-0240
5
Copper bis (dimethyIdithiocarbamate) CURRENT KNOWLEDGE OF
(CDDC) LEACHING AND EFFECTS ON THE
CDDC is a reaction product formed within the ENVIRONMENT
wood after treatment with two different treating All wood preservative treatments consist of
solutions. The first treating solutions contains active ingredients that protect the wood from
copper ethanolamine, and the second solution deterioration by insects and fungi and ingredients
contains sodium dimethyldithiocarbamate. The that “fix” the active ingredients to the wood to
reaction product protects the wood against minimize leaching. Past studies indicate that
attack by fungi and insects. This preservative a small percentage of the active ingredients
does not contain chromium or arsenic. CDDC of all types of wood preservatives do leach
may not penetrate difficult to treat species out of the wood during service. However,
such as Douglas fir as easily as systems that these studies have been primarily conducted
are formulated with ammoniacal solvents. in the laboratory, and it is difficult to extrapolate
Although CDDC is a newly developed preservative their findings to in-service conditions. This is
and has less time in service than conventional because factors such as fixation conditions,
preservatives, it has been tested by accelerated retention in the wood, product size and shape,
methods such as soil blocks and field stakes. type of exposure, and years in service can all
Due to its recent development, this preservative influence the rate of leaching. These factors
may not be readily available in all areas of have also caused somewhat conflicting results
the country. Information about the availability inthose studiesthat have attemptedto determine
of this preservative can be obtained by calling: leaching rates in service.
ISK Biosciences, Memphis, TN 1-800-556
3425. The biological impacts of the small amounts
of chemical leached from treated wood have
Borates not been well-studied under field conditions.
Borate preservatives are salts such as sodium Ingredients in all preservatives are clearly
octaborate, sodium tetraborate, and sodium toxic to a variety of organisms in high
pentaborate that are dissolved in water. Borates concentrations. although laboratory studies
are effective preservatives against both decay indicate that the Ievels leached from the wood
fungi and insects. Borate preservatives are are generally too low to create a biological
diffusible, and with proper treating practices hazard. The environmental mobility of metals
they can achieve excellent penetration in used in wood preservatives appears to be
species that are difficult to treat with other fairly limited, as they readily to bind to soil or
preservatives. Borate preservatives also present sediment constituents within close proximity
a very low hazard to construction personnel to the wood. The organic components leached
and the public. The borate in treated wood from oil-type preservatives tend to decompose
remains water soluble. Therefore, this in the environment. However, factors such as
preservative is only recommended for applications soil and water pH, soil composition, presence
where the wood is kept free from rain water or of microorganisms, and rate of water flow
standing water and out of ground contact. An can influence the environmental mobility of
example of such use is in the construction of leached preservative components. These factors
wooden buildings in areas of high termite have complex and intertwined roles in the
hazard. leaching and subsequent mobility of preservative
components. This may explain, at least in
IMPORTANT NOTICE: DO NOT USE BORATE part, the conflicting results of previous studies.
PRESERVATIVES WHERE THERE IS It is apparent that more informaiion is needed
CONTACT WITH SOIL, RAIN, OR STANDING on leaching and biological impacts of wood
WATER. preservatives under in-service conditions. Studies

6
of the aquatic toxicology of some of these would prevent rapid dispersal of any leached
wood preservatives, sponsored by the treating components, allowing them to accumulate in
industry, are currently in progress, and Forest soil, sediments, and organisms near the treated
Service personnel are beginning to study the wood.
leaching and biological impacts of wood
preservatives in typical Forest Service Generally, habitats most sensitive to the effects
appIications. of in-service losses of components of wood
preservatives are ecologically unique and/or
The conditions presenting the greatest potential provide essential habitat for key species during
for impacting the ecosystem will be those a critical period of the species’ life cycle.
that present both a high potential for leaching Riparian zones, wetlands, meadows, and fish
and the potential for accumulation of metallic spawning and rearing habitats are the most
components in the environment. Within Forest common. Boardwalks and fishing platforms
Service applications, these conditions are are commonly used in these areas. Determination
most likely to be found where treated wood is of which habitats are sensitive needs to be
used in boggy or marshy areas with little made based on local conditions. The challenge
water exchange. These types of sites provide is to utilize the most durable, aesthetically
a severe leaching exposure because of the pleasing, cost effective materials available
low pH and high organic acid content of the whiIe protecting sensitive ecosystems.
water. In addition, the stagnant water conditions

Figure 2. Bridge walkway.

7
RECOMMENDED GUIDELINES Type of Structure
Selection of a Wood Preservative Although not a majorconcern inmanyapplications,
The type of preservative that is most appropriate the appearance of wood treated with ammoniacal
for use depends on the wood species to be copper preservatives (ACZA, CC, ACQ-B)
treated, type of structure, cost, treated wood may not be as uniform and esthetically pleasing
availability, and the particular sensitivities of as the other water-borne preservatives.
specific ecosystems. Conversely, these ammoniacal preservatives
allow better penetration and treatment of
Wood Species larger dimension material such as piling and
Generally, hem-fir and southern pine can be timbers, especially with Douglas fir. Large
adequately treated with any of the commercial glu-lam timbers such as used in bridge supports
wood preservatives, although copper napthenate are often treated with an oil-type preservative
has not been standardized for use with hem- such as pentachlorophenol and copper
fir. CCA is not recommended for treatment of napthenate to reduce problems with checking
Douglas fir. Douglas fir is more readily treated and cracking. Laminated members should
with oil-type or ammoniacal preservatives. not be treated with waterborne preservatives.
CCA is also not recommended for treatment However, the surface characteristic odor and
of hardwoods that will be placed in ground appearance of oil-borne preservatives may
contact. make them less desirable for uses in areas of
frequent human contact, such as hand rails
or sunbathing decks.

In marine construction, or brackish water
such as ocean estuaries, only creosote, CCA,
ACZA, and CC are approved for use. In such
areas south of San Francisco or in Virginia,
dual treatments of creosote and one of the
waterborne treatments may be needed to
prevent attack by all types of marine borers.

Cost and Availability
The relative cost and availability of the different
wood preservatives varies. The phone contacts
listed above, and on the last page, for each
type of preservative can supply such information.

Ecosystem Sensitivities
Although largely undocumented, it is possible
that some preservatives are more appropriate
than others for use in sensitive ecosystems.
For example, CCA has a much lower copper
content than other waterborne preservatives
(except the borates), and thus may pose less
of a threat to copper-sensitive aquatic ecosystems.
Figure 3. Boardwalk in sensitive habitat.

8
(NOTE: There is no evidence at this time to Standard C14 Bridges

suggest that any of the wood preservatives Standard C18: Material in Marine Construction

leach sufficient copper to harm terrestrial or Standard C28: Structural Glued Laminated

freshwater ecosystems). Similarly, preservatives Members and Laminations before Gluing

without arsenic may pose less of a threat to
mammals (such as construction personnel) Treated material that has met these standards
than those that do not contain arsenic. (Once will have the stamp or tag of an American
again, however, there is no evidence that Lumber Standards Committee (ALSC) accredited
arsenic containing wood preservatives, if used inspection agency, (see figure 4). Thesestandards
as intended, cause any harm to people or describe acceptable treating methods and
other mammals). Oilborne preservatives often require that the wood is sufficiently penetrated
produce an oily surface sheen when installed with adequate amounts of preservative for
in stagnant fresh-water applications. This various exposure environments. Avoid wood
may be unacceptable in situations where that is purported to be “treated to refusal”.
appearance is important and waterborne
preservatives may be more appropriate when
extensive contact with fresh water is required.
As more information is obtained about in-
service leaching rates and biological impacts,
it will be possible to make more informed
decisions about the appropriate use of wood
preservatives in sensitive ecosystems. The
wood treating industry is currently developing
a model to assist in this decision-making
process in aquatic ecosystems.

Purchase of a Treated Wood Product
Regardless of the type of preservative, care
should be taken to ensure that the wood is
properly treated and allowed to adequately
“fix” before it is placed in service.
Figure 4. Stamp of Accredited inspection Agency.
Courtesy of Western Wood Preservers’ Institute.
Treatment
Purchasers of treated wood should require
that the wood is treated in accordance with Incising is a technique that is used to increase
American Wood Preserver’s Standard C1 (all preservative penetration and retention in species
products) and other standards as shown: such as Douglas fir. Douglas fir should be
incised regardless of the type of preservative
Standard C2: Lumber, timbers, bridge ties,
used. Incising is especially important in larger
and mine ties
dimension material such as timbers that are
Standard C3: Piling
in ground contact load bearing applications.
Standard C4: Poles
Smaller dimension material that is not in
Standard C5: Posts
contact with ground or water, such as decking,
Standard C9: Plywood
may perform adequately without incising in
some applications. Although not required by

9
AWPA Standards, incising of southern pine is ACZA and ACQ-B
beneficial when larger dimension material, The key to achieving fixation with these
such as timbers, is treated. These larger preservatives is to allow volatilization of the
pieces often have at least one heartwood ammonia. This can be accomplished by air or
face that is poorly penetrated by preservatives. kiln-drying. The BMP’s state that air drying
Availability of incised southern pine is limited. shall be conducted for a minimum of three
weeks at a temperature above 16°C (60°F).
Fixation and Surface Cleanliness This time can be reduced to one week if the
Laboratory studies indicate that wood preservative material is conditioned in the treating cylinder.
leaching is greatly increased if proper techniques At lower temperatures a heat source or kiln
are not used to prevent surface residues and drying should be used. There is currently no
allow adequate fixation. Meeting these conditions commonly used method to ensure fixation in
is primarily the responsibility of the commercial ACZA and ACQ-B, although wood that has
treater, but treated wood purchasers should been thoroughly dried is acceptable. However,
also take measures to ensure that the wood if the wood releases a strong ammonia odor,
will have minimal leaching. fixation is not complete. Although CC has not
yet been included in the BMP’s, the same
Purchasers should specify and require assurance fixation conditions will apply.
that the material be produced in compliance
with the “Best Management Practices For ACQ-D, and CDDC
The Use Of Treated Wood In Aquatic These newer formulations have not yet been
Environments”, a publication of the Western included in the BMP’s. As a general rule,
Wood Preservers’ Institute and Canadian Institute however, wood that has been thoroughly re-
for Treated Wood, USA Version, revised January dried after treatment is properly fixed.
1995. (For information or to obtain a copy of
this booklet, call The Western Wood Preservers’ Pentachlorophenol, creosote, and copper
Institute, 206-693-9958). Although these BMP’s naphthenate
have not yet been adopted by the industry in With oil-type preservatives, the primary concern
areas other than on the west coast, purchasers is surface cleanliness and ensuring that excess
in other areas can require that these practices preservative does not “bleed” or ooze back
be used. In brief, these BMP’s describe the out of the wood. Accordingly, the BMP’s require
following procedures to ensure adequate fixation: that treatment techniques such as expansion
baths and steaming be used to produce a
CCA clean surface.
Following treatment, the wood should be either
air seasoned, kiln dried, steamed, or subjected The purchaser can take steps to ensure that
to a hot water bath. It should then be evaluated the wood will be produced according to the
with the chromotropic acid test (AWPA Standard BMP’s described above. It is important to
A3-11, 1992) to ensure that fixation is complete. realize that proper fixation may take time.
Since the fixation process is temperature Thus, material should be ordered well before
dependent with air seasoning (the most common it is needed so that the treater can hold the
fixation method) fixation may take several wood for the necessary time. Similarly, if the
weeks to complete in winter conditions. wood is ordered in advance, the purchaser
may be able to store it under cover, allowing
further drying and fixation to occur. In general,

10
Figure 5. Worksite

allowing the material to air dry before use is a 2. Placetrail crossings ofsensitive ecosystems
good practice for ensuring fixation, minimizing at their narrowest points
leaching, and reducing risk to construction
personnel. With all the preservatives, inspect 3. Minimize number of stream crossings
the wood for surface residue; it is important
that wood with excessive surface residue not 4. Review available guidelines for specific
be placed in service. sensitive species.

Use of a Treated Wood Product Construction and Handling
Site selection, construction and handling practices Purchasers of treated wood should be supplied
can help to ensure that the risks of using with a consumer information sheet that describes
preservative treated wood products are safe handling practices. The handling practices
minimized. describes should be followed. In general,
whenever working with treated wood (and
Site Selection even untreated wood), it is important that
1 . Stay as far away from surface water as construction personnel take precautions to
possible since contaminants move less avoid frequent or prolonged inhalation of sawdust
freely in soil than water. by wearing a dust mask or respirator, if the
wood appears wet when cutting, water-proof
11
gloves should be worn. In any case, hands SOURCES OF INFORMATION
should be washed before eating, drinking, or
using tobacco products. TechnicaI
US Forest Products Laboratory

During construction, any holes or cuts that
penetrate into untreated wood should be field- One Gifford Pinchot Drive

treated with preservative. Typically, copper Madison, WI 53705-2398

napthenate is used for this application. However, Telephone: 608-231-9200

care should be taken that preservative is not Fax: 608-231-9592

allowed to drip or spill into the environment.
Whenever possible, field treat the exposed Standards
surface prior to assembly of the structure in a American Wood Preservers’ Association
sensitive area. Do not place the field-treated PO Box 286
wood into water or soiI until alI excess preservative Woodstock, MD 21163-0286
has been either wiped-off or soaked into the Telephone: 410-465-3169
wood. Fax: 410-465-3195
Care should be taken during construction
that sawdust and other wood waste does not SOURCES OF SUPPLY AND
enter the environment. It should be collected ENVIRONMENTAL REGULATIONS
and removed from the site. Treated wood for
disposal is not listed as a hazardous waste American Wood Preservers’ Institute

under federal law and can be disposed of in 1945 Old Gallows Rd., Suite 550

any waste management facility authorized Vienna, VA 22812

under state and local law to manage the material. Telephone: 703-893-400

Fax: 703-893-8492

IMPORTANT NOTICE! STATE AND LOCAL
JURISDICTIONS MAY REGULATE THE USE, Western Wood Preservers’ Institute

REUSE AND DISPOSAL OF TREATED WOOD 601 Main Street, Suite 401

AND TREATED WOOD CONSTRUCTION Vancouver, WA 98660

WASTE. USERS SHOULD CHECK WITH
Telephone: 360-693-9958

STATE AND LOCAL AUTHORITIES FOR
Fax: 360-693-9967

ANY SPECIAL REGULATIONS RELATING
TO TREATED WOODS.

lNFORMATION ABOUT REGULATIONS IN
SOME AREAS CAN ALSO BE OBTAINED
BY CONTACTlNG THE WESTERN WOOD
PRESERVERS’ INSTITUTE OR AMERICAN
WOOD PRESERVERS’ INSTITUTE.
Printed on recycled paper

^ U.S. GOVERNMENT PRINTING OFFICE: 1995-683-100/23004

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