DEAS 324: 2023 
ICS 71.100.50  
 
© EAC 2023                                                                                                                        Second Edition 2023  
 DRAFT EAST AFRICAN STANDARD  
Copper/chromium/arsenic compositions for the preservation of timber — 
Method for timber treatment  
EAST AFRICAN COMMUNITY  
 DEAS 324: 2023 
ii © EAC 2023 – All rights reserved  
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Violators may be prosecuted . DEAS 324: 2023 
© EAC 2023 – All rights  reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Exchange of information  ................................ ................................ ................................ ......................  2 
4.1 General  ................................ ................................ ................................ ................................ ...................  2 
4.2 Essential items to be supplied to the treater  ................................ ................................ ......................  2 
4.2.1  Commodity specification  ................................ ................................ ................................ ......................  2 
4.2.2  Timber to be treated  ................................ ................................ ................................ ..............................  2 
4.2.3  Method of treatment  ................................ ................................ ................................ ..............................  2 
4.3 Items to be agreed between the treater and the customer  ................................ ...............................  2 
4.3.1  General  ................................ ................................ ................................ ................................ ...................  2 
4.3.2  Condition of timber for treatment  ................................ ................................ ................................ ........  2 
4.3.3  Material reduced pressure for pressure sensitive  ................................ ................................ .............  2 
4.3.4  Analysis of working solution  ................................ ................................ ................................ ...............  2 
4.3.5  Analysis of the treated timber  ................................ ................................ ................................ ..............  3 
4.3.6  Inspection of treatment operation  ................................ ................................ ................................ ....... 3 
4.3.7  Drying after treatment  ................................ ................................ ................................ ...........................  3 
4.3.8  Post -treatment operations  ................................ ................................ ................................ ....................  3 
5 Preservative solution  ................................ ................................ ................................ ............................  3 
5.1 Concentration of working solution  ................................ ................................ ................................ ...... 3 
5.2 Storage temperature  ................................ ................................ ................................ .............................  3 
5.3 pH value  ................................ ................................ ................................ ................................ ..................  3 
5.4 Analysis of working solution  ................................ ................................ ................................ ...............  3 
6 Condition and preparation of timber for treatment  ................................ ................................ ............  3 
6.1 Condition of timber be fore treatment  ................................ ................................ ................................ .. 3 
6.1.1  General  ................................ ................................ ................................ ................................ ...................  3 
6.1.2  Freedom from decay and insect attack  ................................ ................................ ...............................  4 
6.1.3  Moisture content  ................................ ................................ ................................ ................................ .... 4 
6.1.4  Fabrication before treatment  ................................ ................................ ................................ ................  4 
6.2 Incising  ................................ ................................ ................................ ................................ ...................  4 
7 Loading in treatment cylinder  ................................ ................................ ................................ ..............  4 
7.1 Selection of timber  ................................ ................................ ................................ ................................  4 
7.2 Stacking in the cylinder  ................................ ................................ ................................ ........................  4 
8 Treatment schedules ................................ ................................ ................................ .............................  5 
8.1 General  ................................ ................................ ................................ ................................ ...................  5 
8.2 Full cell process  ................................ ................................ ................................ ................................ .... 5 
8.2.1  Initial vacuum stage  ................................ ................................ ................................ ..............................  5 
8.2.2  Flooding  ................................ ................................ ................................ ................................ .................  5 
8.2.3  Pressure stage  ................................ ................................ ................................ ................................ ....... 5 
8.2.4  Final vacuum stage  ................................ ................................ ................................ ...............................  5 
8.3 Lowry empty cell process  ................................ ................................ ................................ ....................  5 
8.3.1  Floodin g ................................ ................................ ................................ ................................ .................  5 
8.3.2  Pressure stage  ................................ ................................ ................................ ................................ ....... 5 
8.3.3  Final vacuum stage  ................................ ................................ ................................ ...............................  5 
8.4 Confir mation of treatment  ................................ ................................ ................................ ....................  6 
9 Handling and drying of treated timber  ................................ ................................ ................................  6 
9.1 Handling of treated timber  ................................ ................................ ................................ ....................  6 DEAS 324: 2023 
iv © EAC 2023 – All rights reserved  
 9.2 Drying of treated timber  ................................ ................................ ................................ ........................ 6 
Annex  A (normative)  Post -treatment operations on treated timber  ................................ ............................. 7 
A.1 Additional preservative treatment after fabrication  ................................ ................................ ........... 7 
A.2 Painting  ................................ ................................ ................................ ................................ ................... 7 
A.3 Adhesive application  ................................ ................................ ................................ ............................. 7 
A.4 Application of metal fixing  ................................ ................................ ................................ .................... 7 
Annex  B (Normative)  Method for determination of concentration of working solution  ............................. 9 
B.1 Apparatus  ................................ ................................ ................................ ................................ ............... 9 
B.2 Procedure  ................................ ................................ ................................ ................................ ............  10 
Annex  C (normative)  Penetration  ................................ ................................ ................................ ..................  11 
Annex  D (normative)  Methods for determination of moisture content of timber before treatment  ....... 12 
D.1 Oven drying method  ................................ ................................ ................................ ...........................  12 
D.1.1  Sample selection ................................ ................................ ................................ ................................ . 12 
D.1.2  Apparatus  ................................ ................................ ................................ ................................ ............  12 
D.1.3  Procedure  ................................ ................................ ................................ ................................ ............  12 
D.1.4  Calculation  ................................ ................................ ................................ ................................ ...........  12 
D.2 Moisture meter method  ................................ ................................ ................................ ......................  13 
D.2.1  Sampling  ................................ ................................ ................................ ................................ ..............  13 
D.2.2  Apparatus  ................................ ................................ ................................ ................................ ............  13 
D.2.3  Procedure  ................................ ................................ ................................ ................................ ............  13 
Bibliography  ................................ ................................ ................................ ................................ .....................  14 
 DEAS 324: 2023 
© EAC 2023 – All rights  reserved  v 
 Forewor d 
Development of the East African Standards has been necessitated by the need for harmonizing requirements 
governing quality of products and services in the East African Community. It is envisaged that through 
harmonized standardization, trade barriers tha t are encountered when goods and services are exchanged 
within the Community will be removed.  
The Community has established an East African Standards Committee  (EASC)  mandated to develop and 
issue East African Standards  (EAS) . The Committee is composed of  representatives of the National 
Standards Bodies in Partner States, together with the representatives from the public and private sector 
organizations  in the community .  
East African Standards are developed through  Technical Committees that are representa tive of key 
stakeholders including government, academia, consumer groups, private sector and other interested parties. 
Draft East African Standards are circulated to stakeholders through the National Standards Bodies in the 
Partner States. The comments rec eived are discussed and incorporated before finalization of standards, in 
accordance with the Principles and procedures for development of East African Standards. XXXXXX.  
East African Standards are subject to review, to keep pace with technological advance s. Users of the East 
African Standards are therefore expected to ensure that they always have the latest versions of the standards 
they are implementing .  
The committee responsible  for this document is Technical Committee EASC /TC 022, Wood, timber and thei r 
products . 
Attention is drawn to the possibility that some of the elements of this document may be subject of patent 
rights. EAC shall not be held responsible for identifying any or all such patent rights.  
This second  edition cancels and replaces the first edition ( EAS 324:2002 ), which has been technically rev ised.  
 DRAFT EAST AFRICAN STANDARD  DEAS 324:  2023 
 
© EAC 2023 – All rights reserved  1 
 Copper/chromium/arsenic compositions for the preservation of timber — 
Method for timber treatment   
1 Scope   
This Draft East African Standard prescribes  procedures for treatm ent of timber using  water borne 
copper/chromium/arsenic (CCA) preservative formulations.  
It does not specify details of treatment relating to specific end uses for which reference to the relevant 
commodity specification should be made.  
2 Normative references   
The following documents are referred to in the text in such a way that some or all of their content constitutes 
requirements of this document.  For dated references, only the edition cited applies. For undated references, 
the latest edition of the referenced document (in cluding any amendments) applies.  
EAS 24, Glossary of terms used in timber industry  
EAS 124, Rounding off numerical values   
EAS 325, Wood preservatives and treated timber — Guide to sampling and preparation of wood preservative 
and treated timber for analys is 
EAS 326, Wood preservation by means of copper/chromium/arsenic compositions — Specification  
3 Terms and definitions   
For the purposes of this document, the terms and definitions given in EAS 24  and the following apply.  
ISO and IEC maintain terminologica l databases for use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
commodity specification  
any document providing details of preservative treatments  required for a specific end use.  
 “NOTE – Examples of such documents are East African Standard specification, a published specification or 
recommendation of a relevant trade association of public authority.”  DEAS 324: 2023 
2 © EAC 2023 – All rights reserved  
 4 Exchange of information  
4.1 General  
In order  to carry out a treatment according to this East African Standard, it is necessary for the operator of the 
treatment process to be provided with the following supplementary information, which shall be fully 
documented. The information required consists of  
a) essential information to be supplied to the treater (see 4.2) ; and 
b) items to be agreed between the treater and the customer (see 4.3).  
4.2 Essential items to be supplied to the treater  
4.2.1  Commodity specification  
Any commodity specification to which refer ence is required for information or operating detail shall be clearly 
identified.  
4.2.2  Timber to be treated  
The following information shall be stated where relevant:  
a) The timber species (see 7.1 and 8.1),  
b) whether the end use is for poles (see 6.1.3),  
c) whet her incising is required (see 6.2),  
if not specified in the relevant commodity specification.  
4.2.3  Method of treatment  
The treatment parameters shall be identified and precise schedule, shall be specified . Including  pressure  
levels  and periods for each tr eatment stage (see Clause 8) unless these details are given in  the relevant 
commodity specification.  
4.3 Items to be agreed between the treater and the customer  
4.3.1  General  
If required by agreement between the treater and the customer, the items in 4.3.2  to 4.3.8 shall be stated.  
4.3.2  Condition of timber for treatment  
It shall be stated whether timber showing signs of attack by sapstain and fungi pinhole borers is an acceptable 
constituent of the charge (see 6.1.2)  
4.3.3  Material reduced pressure for pre ssure sensitive  
It shall be stated whether a minimum hydraulic pressure of 10 bar may be used with a consequent lengthening 
of the standard pressure period (see 8.2.3)  
4.3.4  Analysis of working solution  
It shall be stated whether analysis of the working so lution is required.  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  3 
 4.3.5  Analysis of the treated timber  
It shall be stated whether analysis of the treated timber in accordance with TZS 660 is required and if so, the 
sampling procedure required.  
4.3.6  Inspection of treatment operation  
It shall be stated  whether the customer is to observe the treatment operation on site (see 8.4).  
4.3.7  Drying after treatment  
It shall be stated whether the treated timber is to be dried to specified moisture content and, if so, the moisture 
content required (see 9.2).  
4.3.8 Post -treatment operations  
It shall be stated whether any post treatment operations are to be undertaken prior to delivery of the timber. If 
so the operations shall be in accordance with Annex A.  
5 Preservative solution  
5.1 Concentration of working solut ion 
The working solution shall be prepared from one of the mixtures specified in EAS 326: 2002 (see clause 2) 
and shall be mixed thoroughly. The concentration of this working solution before use, when determined in 
accordance with Annex B, shall be not les s than that specified in the relevant commodity specification.  
5.2 Storage temperature  
The solution shall be stored at normal ambient temperature except that it shall not at any time be allowed to 
exceed 40 °C.  
5.3 pH value  
The pH value of the working solu tion shall comply with Clause 5 of EAS 326.  
5.4 Analysis of working  solution  
Solution strength is a function of temperate and specific gravity expressed in weight to volume” . If specified 
(see 4.3.4) the proportions of the active ingredients shall be deter mined in accordance with EAS 324 on 
sample prepared in accordance with EAS 325.  
6 Condition and preparation of timber for treatment  
6.1 Condition of timber before treatment  
6.1.1  General  
On visual inspection, the surface of the timber shall be free from mu d, dirt, inner and outer bark, sawdust and 
shavings, It shall also be free from paint, polish or other surface finish.  DEAS 324: 2023 
4 © EAC 2023 – All rights reserved  
 6.1.2  Freedom from decay and insect attack  
On visual inspection, the timber shall be free from all signs of attack by wood -destroying fun gi or insects 
unless it has been agreed (see 4.3.2) that timber showing signs of attack by sapstain fungi and pinhole borers 
is acceptable.  
6.1.3  Moisture content  
For all timber, unless otherwise specified in a relevant commodity specification, the average  moisture content 
shall not exceed 25 % (m/m) on an oven dry basis. The moisture content shall be determined in accordance 
with one of the methods given in Annex D.  
For overhead line poles, the maximum average moisture content in the charge shall be not mo re than 25 % 
(m/m) on an oven dry basis for the outer 27mm. The moisture content of any individual pole shall not exceed 
28 % (m/m).  
6.1.4  Fabrication before treatment  
All timber shall be sawn or planed before treatment to achieve the finished cross -sectio n at the moisture 
content at which the timber is to be used.   
NOTE  As far as possible, all crosscutting, boring, drilling or other fabrication should be carried out before treatment 
(see A.1).  
6.2 Incising  
If incising is specified, the incisions shall be made parallel to the general direction of the grain. They shall 
penetrate to a depth of approximately 20 mm and be spaced 25 mm apart in rows extending across all four 
faces of the timber. The distance between the rows shall be 60 mm and incisions in adjac ent rows shall not be 
in direct line but staggered at intervals of approximately 6 mm, i.e. incisions in every fourth row are in direct 
line. 
NOTE  Sawn timbers rated as resistant to preservative (e.g. East African pencil cedar), 75 mm or thicker, and 
inten ded for exterior use, may benefit from incising before treatment.  
If incising is specified in the relevant commodity specification for other sawn timber, it shall be carried out as 
described above.  
7 Loading in treatment cylinder  
7.1 Selection of timber  
If it is not possible to segregate timber for treatment so that a charge consists of timbers of the same species 
and/or resistance to penetration, the most resistant species in the charge shall be identified (see 8.1).  
NOTE  It is preferable to segregate the timber.  
7.2 Stacking in the cylinder  
7.2.1  The pieces of timber shall be stacked so that the solution will have access to all faces of the timber.  
7.2.2  Sawn  timber may be separated by sticks or laths at appropriate intervals.  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  5 
 8 Treatment schedules  
8.1 General  
The timber shall be treated with an aqueous solution of the preservative in accordance with either:  
a) the relevant commodity specification;  
b) the full cell vacuum and pressure process; or  
c) the lowry empty cell pressure impregnation process.  
The treatment schedules shall be as specified in 8.2 or 8.3 as appropriate.  
The treatment schedule for charges of mixed species or of timber of different resistance to penetration shall 
be that appropriate to the most resistant of the timber species present (see also An nex C and Note under 6.2).  
8.2 Full cell process  
8.2.1  Initial vacuum stage  
Subject the timber to an initial vacuum of at least - 0.65 bar and maintain at this pressure for the period of time 
specified in the relevant commodity specification.  
8.2.2  Floodin g 
On completion of the initial vacuum stage flood the cylinder with preservative solution before releasing the 
vacuum.  
8.2.3  Pressure stage  
Subject the timber and preservative in the cylinder to a minimum hydraulic pressure of 1 0 bar for the period of 
time specified in the relevant commodity specification. The pressure period begins when the pressure first 
reaches 10 bar. 
8.2.4 Final vacuum stage  
At the end of the pressure stage. Empty the cylinder of preservative solution and apply a final vacuum. 
Release  the vacuum as soon as the gauge reading reaches a vacuum of -0.65 bar or after 15 min, whichever 
is sooner.  
8.3 Lowry empty cell process  
8.3.1  Flooding  
After loading, flood the cylinder with preservative solution at atmospheric pressure.  
8.3.2  Pressure st age 
Subject the timber and preservative in the cylinder to the pressure and period described in 8.2.3.  
8.3.3  Final vacuum stage  
If a final vacuum stage is specified by the relevant commodity specification, carry out the procedure described 
in 8.2.4.  DEAS 324: 2023 
6 © EAC 2023 – All rights reserved  
 8.4 Confirmation of treatment  
During the treatment schedule records shall be kept of the actual treatment schedule.  
Detailed records of the treatment schedule shall be available to the customer on request, in addition to a 
certificate stating that the specificat ion has been met and including any relevant item listed in Clause 4.  
9 Handling and drying of treated timber  
9.1 Handling of treated timber  
Treated wood shall be held for  a minimum of 48 h or until drip -dry, whichever is the longer, before dispatch or 
erection.  
The fixation  Chart  gives an indication of the time versus timber temperature required for fixation to be 
achieved   
 
Figure – WCCA fixation chart  
NOTE  Fixation of the preservative may take up to 14 days and this should be taken into account before u se with 
metal fittings (see A.4).  
CAUTION !  Skin contact with timber still wet after treatment should be avoided. If it is necessary to handle 
treated timber while wet, it is essential that protective gloves be worn.  
9.2 Drying of treated timber  
If it is s pecified that the treated timber shall be dried to a specific moisture content (see 4.3.7) the moisture 
content shall be determined by the method described in EAS 325.  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  7 
 Annex  A 
(normative)  
 
Post -treatment operations on treated timber  
A.1 Additional preser vative treatment after fabrication  
Liberally treat the exposed surfaces or bolt holes of timbers that are cross -cut, notched or drilled for  bolts after 
any pressure impregnation treatment, by brushing, spraying or dipping with a preservation  formulation 
recommended by the preservative manufacturer, un less otherwise specified in the relevant commodity 
specification.  
NOTE 1  The treater may undertake post -treatment operations by agreement (see 4.3.8), or by the user of the treated 
timber.  
NOTE 2  It should be b orn in mind that this remedial treatment would not replace the full  preservative protection of the 
impregnation process.  
A.2 Painting  
Allow to dry to a suitable moisture content as specified for any treated timber that is to be stained,  painted or 
varnishe d. Brush the surface of the dried timber to remove any dirt or excess preservative salts.  
NOTE 1  Provided that the timber has been dried to a moisture content less than 25 % (m/m) any normal painting 
system may  be used.  
NOTE 2  Paint does not key satisfacto rily into wet timber whether treated or untreated.  
A.3 Adhesive application  
A.3.1  Before application of the adhesive lightly sand the treated timber or brush it with a wire brush to  
remove excess preservative salts. Follow the adhesive manufacturer  instruc tions concerning the moisture 
content.  
NOTE  For internal dry conditions phenol -formaldehyde, casein or urea -formaldehyde resin adhesives are 
recommended.  
A.3.2  For external and damp conditions, resorcinol or pheno l-formaldehyde types are recommended.  
NOTE  Materials containing formaldehyde can release formaldehyde gas or vapor into the air. Formaldehyde is 
classified as a probable human carcinogen under conditions of unusually high or prolonged exposure. Therefore, it is 
important to insert a note of precaut ions.  All necessary safety precautions should  be taken when using adhesives.  
A.4 Application of metal fixing  
Certain types of metal fixing will be liable to corrode if the wood in which they are embedded becomes  wet. 
The presence of CCA preservatives in th ese conditions will increase the risk of corrosion. Where  there is a 
risk that the moisture content of the timber will exceed 20% (m/m), choose the metal fixings so that the effects 
of corrosion are minimized taking the following into account:  DEAS 324: 2023 
8 © EAC 2023 – All rights reserved  
 a) Do not fix f ittings to the timber until 14 days after treatment or until the moisture content has fallen 
below 20 % (m/m).  
b) If the timber is likely to become wet and a long service life is required, use fittings of austenitic 
stainless steel (excluding free machining g rades), or copper or silicon bronze in preference to other 
types of fittings.  
c) Take into account the likelihood of corrosion against intended service life of the component in 
selecting such fittings.  
NOTE  If only occasional dampness is expected, coated low carbon steel (e.g. sherardized, galvanized or cadmium 
plated) fittings may be used. Better performance will be obtained from fittings with thicker coatings.  
d) Use fittings of unprotected low carbon steel, iron and aluminium only on timber, the moisture conte nt 
of which is expected to remain below 20 % (m/m) for most of its service life and then only in indoor or 
well protected environments. Do not use aluminium alloys containing copper.  
e) Do not use sheet aluminium roof coverings or claddings in direct contact with CCA treated timber.  
NOTE  These materials may be used if a bitumen emulsion, bitumen barrier paper or felt of other suitable water 
repellent barrier is placed between the timber and the aluminium sheeting.  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  9 
 Annex  B 
(Normative)  
 
Method for determination of concentration of working solution  
B.1 Apparatus  
B.1.1  Hydrometer, suitable for the uses and graduated for medium surface tension calibrated relative to 
water at a temperature of 15.5 °C.  
B.1.2  Glass cy linder, of nominal capacity 500 mL preferably ungraduated.  
B.1.3  Thermometer, total immersion type and suitable for measuring up to 40 °C.  
 
DEAS 324: 2023 
10 © EAC 2023 – All rights reserved  
 B.2 Procedure  
B.2.1  Obtain a representative 500 mL sample of the working solution.  
B.2.2  Transfer the solution to the glass cylinder (B.1.2) and place it on a level surface.  
B.2.3  Insert the thermometer (B.1.3) into the solution, wait until the temperature has reached equilibrium 
with its surroundings and remains constant for 1 min and record  the temperature before removing the 
thermometer.  
B.2.3  Place the clean, dry hydrometer (B.1.1) in the solution and when the hydrometer has settled to a 
constant level, record the height of the solution level against the graduated scale on the stem of the 
hydrometer, with the eye directly in line with the surface of the solution to the nearest 0.005.  
B.2.4  Using a hydrometer calibration, chart the accuracy which has been verified by analysis (see Figure 
B.1). Place a straight edged ruler across the temperat ure and hydrometer reading scales at the points 
recorded for the solution sample.  
B.2.5  The concentration of the solution (in g/L) of the preservative type under test is read at the point of 
intersection on the concentration scale.  
 
Figure B.1 — Hydromete r reading: Concentration calibration chart for working solutions of type 1 and 
type 2 CCA preservatives  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  11 
 Annex  C 
(normative ) 
 
Penetration   
C.1 The effectiveness of any preservative treatment depends not only  on the amount of preservative taken 
up by the timber, but also on the depth of penetration achieved during the treatment process.  However, in all 
cases, sapwood defined as permeable should be completely penetrated.  
C.2 If it is a requirement of the releva nt commodity specification to determine the degree of penetration, this 
shall be carried out in accordance with the respective commodity specification.  DEAS 324: 2023 
12 © EAC 2023 – All rights reserved  
 Annex  D 
(normative)  
 
Methods for determination of mois ture content of timber before 
treatment   
D.1 Oven drying method  
D.1.1  Sample selection  
D.1.1.1  Cut a sample consisting of a full cross section not le ss than 300 mm from one end and 13 mm to 
19 mm thick.  
D.1.1.2  Alternatively, if it is not possible to cut t he timber, take borings totalling  not less than 8 g, not less 
than 230 mm from one end. Using a test borer consisting of a hollow auger and extractor  bore from the  
sapwood face to the centre of the section. For timbers having a smallest dimension of 150 mm  or over, take 
borings to a depth of 25 mm or the full depth of the sapwood if this exceeds 25 mm.  
D.1.1.3  Put the sample into a stoppered weighing bottle or other airtight contain er immediately after 
extraction if it cannot be weighed at once.  
D.1.2  Appar atus 
Ordinary laboratory apparatus together with electrically -heated drying oven, suitable for the uses  
D.1.3  Procedure  
D.1.3.1  Weigh the sample as soon as possible after cutting or extraction, m1 and place it in the oven 
(D.1.2) which has been already ad justed to a temperature of 103 °C ± 2 °C. Remove the sample periodically, 
cool it in a desiccator and reweigh it (m2).  
D.1.3.2  Dry the sample to constant mass such that the loss in mass for a drying interval of 6 h does not 
exceed 0.1 %.  
D.1.4  Calculation  
Calculate the moisture content (w) as a percentage of the dry mass according to the following equation:  
 
where 
m1 is the mass in grams of the sample when wet;  
m2 is the mass in grams after drying.  DEAS 324: 2023 
© EAC 2023 – All rights  reserved  13 
 D.2 Moisture meter method  
D.2.1  Sampling  
Take components t o be measured from random positions in the charge.  
NOTE  The number of heartwood and sapwood faces to be sampled should reflect the relative proportions of these 
types of wood in the charge as a whole.  
D.2.2  Apparatus  
Moisture meter, electrical resistance t ype, provided with insulated electrodes and calibrated for the species of 
wood to be measured. It shall be capable of making an individual measurement with an error of not more than 
2 % (m/m) for moisture contents between 7 % and 29 % (m/m).  
D.2.3  Procedur e 
D.2.3.1  If the total number of components in the charge is n, take moisture readings on at least √(n/2) 
separate components. Measure the moisture content in the middle of each face.  
D.2.3.2  Drive the electrodes  into the wood to a depth appropriate to the type of wood as given in Table 1, 
so that the line between the tips of the electrodes is in the direction of or perpendicular to the grain, in 
accordance with the instructions for the type of meter used.  
D.2.3.3  Make at least three measurements in each measuring a rea 10mm to 15 mm apart to avoid any 
accidental error due to electrodes penetrating an inner invisible defect in the wood.  
D.2.3.4  The moisture content is given by the mean of the averages of the three measurements on each 
face.  DEAS 324: 2023 
14 © EAC 2023 – All rights reserved  
 Bibliography  
EAS 324:2002 , Copper/chromium/arsenic compositions for the preservation of  timber — Method for timber 
treatment  
 DEAS 324: 2022    
 
© EAC 2022 – All rights reserved