ASTM D1758-96

Standard Test Method of Evaluating Wood Preservatives by Field Tests with Stakes

SCOPE
1.1 This test method covers accelerated procedures for determining the relative permanence and effectiveness of wood preservatives in stakes exposed in field plots.  
1.2 The requirements for preparation of the material for testing and the test procedures appear in the following order:  Sections Summary of Test Method 3 Test Plot 4 Test Specimens 5 Pretreatment Selection of Test Stakes 6 Treatment Procedure 7 After Treatment Handling of Test Stakes 8 Installation of Stakes 9 Inspection of Specimens 10 Evaluation of Results 11 Reports 12
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Dec-1995
• ICS: 71.100.50 - Wood-protecting chemicals
• Technical Committee: D07 - Wood

Relations

• Replaced By: ASTM D1758-02 - Standard Test Method of Evaluating Wood Preservatives by Field Tests with Stakes
• Effective Date: 10-Sep-2002

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 1758 – 96
Standard Test Method of
Evaluating Wood Preservatives by Field Tests with Stakes
This standard is issued under the fixed designation D 1758; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope men types, ⁄4-in. square and nominal 2 by 4-in. stakes,
designated hereafter respectively as Method A and Method B.
1.1 This test method covers accelerated procedures for
Method A, using smaller and more numerous specimens, is
determining the relative permanence and effectiveness of wood
preferred for possibly more rapid results, and Method B for
preservatives in stakes exposed in field plots.
longer term tests of a quasi service nature.
1.2 The requirements for preparation of the material for
testing and the test procedures appear in the following order:
4. Test Plot
Sections
4.1 General Requirements—A warm humid climate is pre-
Summary of Test Method 3
Test Plot 4
ferred. Select a natural area of fertile, fallow, level land of
Test Specimens 5
uniform soil character that is moist but well drained and large
Pretreatment Selection of Test Stakes 6
enough to permit expansion of future stake installations. The
Treatment Procedure 7
After Treatment Handling of Test Stakes 8
presence of wood-destroying fungi and active subterranean
Installation of Stakes 9
termites shall be proved by observation or experience and
Inspection of Specimens 10
checked by exposure of suitable small specimens of untreated
Evaluation of Results 11
Reports 12
wood. No natural or artificial fertilizer or other chemicals shall
be applied to the plot during its use as a test ground. Protection
1.3 This standard does not purport to address all of the
against fire, predators and pilferage shall be provided as far as
safety concerns, if any, associated with its use. It is the
practicable.
responsibility of the user of this standard to establish appro-
4.2 Control of Vegetation—As a general rule vegetation
priate safety and health practices and determine the applica-
shall be controlled manually or by suitable mechanical means
bility of regulatory limitations prior to use.
only, with minimum soil disturbance. No chemical controls
2. Referenced Documents
shall be permitted. Weeding and cleaning the plot shall be
uniform over any given test area.
2.1 ASTM Standards:
4.3 Reuse of Ground—Stakes placed in ground that has
D 1413 Test Method for Wood Preservatives by Laboratory
been used previously for test purposes shall not be set closer
Soil-Block Cultures
than 6 in. (150 mm) to any earlier stake location.
D 1625 Specification for Chromated Copper Arsenate
5. Test Specimens
3. Summary of Method
5.1 Selection of Wood—Sapwood of southern pine, with 6 to
3.1 Wood stakes are impregnated with an appropriate series
10 rings per inch, shall be the preferred wood for comparative
of retentions of a preservative, and then handled, prior to
tests. It shall be free of knots, excessive cross-grain and resins
exposure in the field, according to specified procedures. The
or other obvious defects, and it shall show no visible evidence
treated stakes are exposed in the ground to the action of
of infection by mold, stain, or decayed fungi. Whenever
wood-destroying fungi and termites in one or more selected
practicable, select straight-grained wood for the test stakes at
field plots. An index of condition determined from grades
the sawmill. Acceptable freshly cut lumber shall be kiln-dried
assigned to the stakes for degree of decay and termite attack, in
in order to avoid fungus infection before and during shipment.
the course of periodic inspections, is used to express results
The wood shall not have been treated with chemicals to prevent
periodically and at the termination of the test.
sapstain. The dried lumber shall be stored flat in a dry room
3.2 Two test procedures are outlined, employing two speci-
where it can reach an equilibrium moisture content (oven-dry
basis) of 12 % or less. Sapwood or heartwood of any species
This test method is under the jurisdiction of ASTM Committee D-7 on Wood
may be used for special investigations. In such cases the test
and is the direct responsibility of Subcommittee D07.06 on Treatments for Wood
stakes shall be all sapwood or all heartwood in any given
Products.
comparative series. Individual stakes containing both sapwood
Current edition approved April 10, 1996. Published June 1996. Originally
e1
published as D 1758 – 62. Last previous edition D 1758 – 86(1994) . and heartwood shall not be used.
Annual Book of ASTM Standards, Vol 04.10.
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 1758
5.2 Cutting Test Blanks—Test blanks may be sawed from given group of treatments of a preservative shall represent as
the dry lumber in any convenient lengths, usually in multiples far as practicable a series running from low to high absorption
of the stake length. in order to provide data on the effective protective retention
5.3 Test Stake Dimensions—For Method A the test blanks level. The spread in the series shall be designed to straddle the
shall be surfaced four sides as accurately as practicable to 19 expected or predetermined effective retention for outdoor stake
by 19 mm (0.75 by 0.75 in.) and cut to a length of 457 mm (18 tests. This retention may be based on experience, or on
in.). For Method B the test blanks shall be surfaced four sides assumptions from the results of soil-block tests (Specification
as accurately as practicable to 38 by 89 mm (1.5 by 3.5 in.), D 1413). The retention nearest the expected effective retention
and cut to a length of 457 mm (18 in.). The average volume of should be at or near the upper end of the series but lower than
3 3 3
the A stake is 165 cm (10.1 in. ) and of the B stake 1546 cm the highest retention selected. The lowest retention should be
(94.5 in. ). The ratios of surface area to volume of the stakes low enough to permit attack and provide proof of the presence
are respectively 5.4 to 1.0 and 2.0 to 1.0. of tolerant wood-destroying fungi, or termites, or both over the
5.4 Storage of Test Blanks and Prepared Stakes—Working area of the test plot.
stocks of test blanks or surfaced untreated stakes shall be stored 7.5 Number of Stakes to Be Treated—The number of stakes
flat under controlled humidity conditions. to be treated depends on available information and experience.
In no case shall there be less than 10 stakes in a test. As a
6. Pretreatment Selection of Test Stakes
general policy, enough stakes should be treated to provide,
within the graded retention population, extra stakes, or pilot
6.1 Initial Weights—Before impregnation the stakes shall be
numbered and weighed to the nearest 1 g. Discard the upper stakes, that may be removed periodically in the early course of
and lower 2.5 % of the stakes. Any deviation from this a test to determine the presence and progress of fungus or
procedure, such as grouping on a weight or ring count basis, termite attack. Use such stakes where practicable to determine
shall be reported in detail (see 12.1.10). The initial untreated the identity of the attacking fungus and the depletion or change
weights shall be coded T . in character of the preservative tested. As examples, since the
6.2 Coding the Weight—The system of T (tare) designations retentions in the stakes in a given charge will vary around the
is as follows, with all weights recorded in grams: nominal retention for the charge, the above scheme may be
accomplished by treating 20 stakes each in a series of nominal
retention charges as follows:
T = initial weight of the test stake before impregnation;
and
Creosote: 80, 100, 130, 160, and 220 kg/m (5.0, 6.25, 8.13, 10.0, and
T = weight of the test stake after impregnation and after 13.8 lb/ft ).
Pentachlorophenol: 1.5, 3.0, 5.0, 8.0, and 11.0 kg/m (0.094, 0.19, 0.31,
wiping to remove superficial liquid (equals T plus
0.5, and 0.69 lb/ft ).
grams of treating solution absorbed). 3
Chromated copper arsenate: 1.5, 3.0, 5.0, 8.0, and 11.0 kg/m (0.094,
0.19, 0.31, 0.5, and 0.69 lb/ft ).
NOTE 1—The T weight does not apply in certain cases, as in treatments
employing liquefied petroleum gas (see Section 7.7).
7.6 Preservative Analysis—Analyze each preservative or
7. Treatment Procedure
preservative solution prior to treatment. If there is reason to
believe that a change in composition occurs during treatment,
7.1 Preferred Treatment Method—The preferred treatment
analyze after each treatment, and avoid extended use of the
method is a full-cell process, simulating commercial practice
same solution.
as far as practicable with laboratory or pilot plant equipment.
7.7 Treatment Retentions—Determine the amount of preser-
Use an initial vacuum, suitable temperature, and an appropriate
vative absorbed by the individual test stakes as accurately as
pressure period determined by trial lots, but omit the final
possible in terms of kg/m as soon as they have cooled to
vacuum. (See 7.9 for method of obtaining gradient retentions
approximate room temperature (a) by weighing them on
by toluene dilutions.)
suitable scales, or (b) by assay of representative stakes by a
7.2 Standard Reference Preservative—The standard refer-
method appropriate for the preservative concerned.
ence preservative shall be a freshly made aqueous solution of
7.7.1 Preservative retentions in stakes treated with preser-
chromated copper arsenate (CCA-Type C; Specification
vatives in highly volatile solvent carriers cannot be calculated
D 1625; AWPA Standard P 5). Periodically treat not less than
from before and after treatment weights since the solvent is
20 stakes with this preservative by a full-cell process to
3 3
removed during the processing. Retentions must therefore be
retentions of 0.20, 0.40 and 0.60 lb/ft (3.2, 6.4 and 9.6 kg/m ).
Randomize the stakes over the plot area on the same basis as determined by an analysis of treated stakes. This may be
accomplished by one of two methods:
the treated test stakes. Record their condition each inspection.
7.3 Untreated Control Stakes—Install not less than 20 7.7.1.1 Method 1—Several extra stakes (not less than 10)
the same size, species, and density range shall be included in
untreated control stakes of each species of wood and of the
same size used for preservative testing throughout the test area each retention charge. Cross sections of these stakes taken at a
point between 100 and 125 mm (4 and 5 in.) from one end shall
when the plot is first established and each time a new series of
tests is installed. Installation shall be on the same random basis be composited and analyzed. The resultant value shall be the
retention for the entire charge.
as the treated test stakes. Record the condition of the untreated
control stakes at each inspection. 7.7.1.2 Method 2—A sample shall be cut at a point between
7.4 Retention Populations—The treatment retentions in any 100 and 125 mm (4 and 5 in.) from the tip end of each test
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 1758
stake representing half the cross section in 19 mm ( ⁄4-in.) 8. After Treatment Handling of Test Stakes
stakes from a radial side as far as possible. Analyze each
8.1 Stakes Treated with Water Solution—Dry stakes treated
sample. The value determined shall be the retention for each
with water-borne preservatives by air-seasoning, kiln-drying,
stake. Coat surfaces exposed as a result of the sampling with a
or a combination of both. Stack the stakes so that air can
sealer such as a phenolic adhesive.
circulate freely between them until their average moisture
7.7.2 For the usual weight determination remove each stake
content is less than 12 %, oven-dry weight basis, or dry them
individually from the treating chamber, wipe lightly to remove
in an oven or kiln at a temperature not to exceed 140°F until
surface preservative or preservative solution, and weigh
their average moisture content is less than 30 %. If other types
promptly to the nearest 1.0 g (Code T ) (6.2).
2 of conditioning before installation are employed, report the
7.8 Calculation of Retentions—Calculate the retention of
method of after-treatment handling fully. In all cases the drying
preservative or preservative solution as follows:
period shall be long enough, not less than 15 days, for the salt
7.8.1 For undiluted preservatives such as creosote, or pen-
preservatives to set thoroughly.
tachlorophenol petroleum systems for example:
8.2 Stakes Treated with Diluted Oil-Type Preservatives or
with Preservatives Dissolved in Highly Volatile Solvents—
Retention, kg/m 5 1000 G/V (1)
Cross-pile stakes treated with volatile solvent solutions, such
7.8.2 For diluted preservatives such as toluene solutions of
as creosote in toluene, or pentachlorophenol in light petroleum
creosote, pentachlorophenol in petroleum carriers, or preserva-
solvents or in liquefied petroleum gas, horizontally over a flat
tive salts in water solution:
base or other suitable support, or stack in a space rack frame,
in such a manner as to permit free air circulation to all faces of
Retention, kg/m 5 1000 GC/V (2)
the stakes and to facilitate removal of individual stakes for
where:
periodic weighing. Continue the exposure until the average
G =(T − T ) = grams of preservative or preservative
2 1
loss in weight is equivalent to at least 90 % but not more than
solution absorbed by the stake,
95 % of the amount of solvent or diluent is absorbed.
C = grams of preservative or preservative solution system
8.3 Stakes Treated with Undiluted Preservatives—Stack
in 100 g of treating solution, as a decimal fraction, and
stakes treated with undiluted preservatives such as creosote or
V = volume of stake, cm :
pentachlorophenol-petroleum solutions for drying as pre-
3 3
0.000165 m for Method A stakes, and 0.001546 m
scribed for air-seasoning under 8.1 for a period of not less than
for Method B stakes.
15 days to permit drying of any superficial or bleeding liquid.
3 3
To convert kg/m to lb/ft divide by 16.
8.4 Individual Stake Condition—It is essential to maintain
7.8.3 Test Stake Identification—After calculation of treat-
the integrity of the individua
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