DRFT UGANDA STANDARD  
  DUS2098  
First  Edition  
2018 -09-20 
 
 
 Reference number  
DUS 2098:2018  
© UNBS 2018   
  
Preservation of Bamboo and Cane for Non -Structural Purposes - 
Code of Practice   
 DUS 2098 :2018  
ii © UNBS 2018  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract . Users are 
responsible for its correct application  
© UNBS yyyy  
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permission from UNBS.  
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The Executive Director  
Uganda National Bureau of Standards  
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Uganda  
Tel: +256 41 4 333 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 2098:2018  
© UNBS 2098  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 scope  ................................ ................................ ................................ ................................ ................................  1 
2 Normative References ................................ ................................ ................................ ...........................  1 
3 Recommended Preservatives  ................................ ................................ ................................ ........................  1 
3.1.1. Coal far creosote  ................................ ................................ ................................ ................................ ...... 1 
3.1.2. Copper and zinc naphthenates abietates  ................................ ................................ ..............................  1 
3.1.3. Boric acid a nd borax  ................................ ................................ ................................ ................................  2 
3.1.4. Copper -chrome -arsenic (CCA) composition  ................................ ................................ .........................  2 
3.1.5. Acid -copper -chrome (A CC) composition ................................ ................................ ..............................  2 
3.1.6. Copper -chrome -boron (CCB) composition — ................................ ................................ .......................  2 
3.1.7. Copper -8-quirrolinate — ................................ ................................ ................................ ..........................  2 
4 Methods of Treatment  ................................ ................................ ................................ ................................ ..... 2 
4.1 Traditional Treatment Methods  ................................ ................................ ................................ ...................  2 
4.1.1 Leaching  ................................ ................................ ................................ ................................ .....................  3 
4.1.2. Smoking  ................................ ................................ ................................ ................................ ....................  3 
4.1.3. Lime washing  ................................ ................................ ................................ ................................ ............  3 
4.1.4. Baking  ................................ ................................ ................................ ................................ ........................  3 
4.1.5. Natural Dyes, Varnishes and Paints  ................................ ................................ ................................ ....... 3 
4.2 Chemical Preservation  ................................ ................................ ................................ ................................ . 3 
4.2.1. Water borne type  ................................ ................................ ................................ ................................ ...... 4 
4.2.2. Oily Preservatives: Creosote  ................................ ................................ ................................ ..................  4 
4.3. Short -Term Chemical Protection  ................................ ................................ ................................ ...............  4 
4.3.1Spraying  ................................ ................................ ................................ ................................ ......................  4 
4.3.2. Brushing  ................................ ................................ ................................ ................................ ....................  5 
4.3.3. Dipping  ................................ ................................ ................................ ................................ ......................  5 
4.4. Long -Term Chemical Prote ction.  ................................ ................................ ................................ ...............  5 
4.5. Non -Pressure Treatment  ................................ ................................ ................................ ............................  5 
4.5.1Steeping or Butt End Treatment (Capillary Rise) Method  ................................ ................................ ...... 5 
4.5.2. Soaking/Diffusion  ................................ ................................ ................................ ................................ ..... 5 
4.5.3. Hot and Cold Treatment  ................................ ................................ ................................ ...........................  6 
4.5.4. Sap Replacement Treatment : Modified Boucherie Process  ................................ ................................  6 
4.6. Pressure Treatment  ................................ ................................ ................................ ................................ ..... 6 
4.6.1. Vacuum Process  ................................ ................................ ................................ ................................ ....... 7 
4.6.2. Full cell Process  ................................ ................................ ................................ ................................ ....... 7 
4.6.3. Empty Cell Process  ................................ ................................ ................................ ................................ .. 7 
4.6.4. Fast Fluctuating Pressure Process  ................................ ................................ ................................ ........  7 
5 Choice of Preservative and Method of Treatment  ................................ ................................ .......................  7 
6 Samples  ................................ ................................ ................................ ................................ ............................  7 
7 Testing of P reservative in Treated Material  ................................ ................................ ................................ .. 8 
7.1 Determination of Absorption of the Preservative  ................................ ................................ .....................  8 
7.2 Determination of Presence of the Pre servative  ................................ ................................ ......................  10 
Bibliography  ................................ ................................ ................................ ................................ ......................  13 
 DUS 2098 :2018  
iv © UNBS 2018  – All rights reserved  
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade , Industry and 
Cooperatives establi shed under Cap 327 , of the Laws of Uganda , as amended .  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission  on Food Standards, and  
(c) the National Enquiry Point on TBT  Agreement  of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, consumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the  
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
The committee responsible for this document is Technical Committee UNBS /TC 12, furniture   
:  
  DRAFT UGANDA STANDA RD DUS 2098:2018  
 
© UNBS 2018  – All rights reserved  1 
 Preservation of Bamboo and Cane for Non -Structural Purposes 
-Code of Practice  
1 scope  
This standard covers the types of preservatives  and method of treatment of bamboos and canes,  used both 
indoor and outdoor for non -structu ral purposes. It also includes recommendations on the  choice of treatment 
depending on the various uses  to which the bamboo and cane are put.    
 This standard does not cover the treatment of  bamboo  meant for structural purposes.  
2 Normative R eferences   
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies   
 
DUS  2099 Preservation  of timber — Code of practice  
DUS 3000,  Code of practice for preservation of bamboo for structural purposes   
 DUS 2112 -1:2018, Water soluble type wood preservative –Part 1; Acid-copper -chrome (ACC) wood 
preservative  
DUS 2112 -2:2018, Water s oluble type wood preservative –Part 2; copper -chrome -boron (CCB) wood 
preservative  
US 32 4, Copper -chrome -arsenic (CCA) wood preservative  
US 32 3, Specification  for creosote oil for use as wood preservatives   
3 Recommended P reservatives  
3.1 The following are  the various preservatives  recommended for treatment of bamboo and cane for  non-
structural purposes:  
 
3.1.1.  Coal  far creosote  
This is a fraction of coal  tar distillate with a boiling point range  above 2000C and is widely used as an  
admixture with fuel oi l. A creosote fuel oil  mixture in the ratio 3:7 is found suitable. The  fuel oil ensures stability 
to creosote against  evaporation and leaching from the treated  bamboo or cane. The creosote  used shall  
conform to US 323 . 
 
3.1.2 . Copper  and zinc naphthenates  abiet ates  
 These are copper and zinc  salts of Naphthenic/Abietic acids.   
2 © UNBS 2018  – All rights reserved  
  
 
3.1.3 . Boric  acid and borax  
These have been  used successfully against lyctus borers. A  mixture of both in  ratio 1 : 1.5 is found more  
suitable . 
 
3.1.4 . Copper -chrome -arsenic (CCA) c omposition   
 A typical composition of this  preservative comprises copper sulphate  (CuS04.5H 2O), arsenic pentaoxide  
(As 2O5.2H 2O) and sodium or potassium  bichromate (Na 2Cr2O7.2H 2O or K2Cr2O2.2H 2O) in the proportion of 3: 
I: 4; conforming  to US EAS 324  
 
3.1.5 . Acid -copper -chrome (A CC) composition  
A typical composition of this preservative  comprises 1.68 parts of chromic acid  (Cr 2O3) (equivalent to 2.5 parts 
of sodium  bichromate), 50 parts of copper sulphate  (CuSO 4.5H 2O) and 47.5 parts of sodiu m bichromate 
(Na2Cr2O2.2H 2O); conforming  to DUS 2112 -2:2018  
 
3.1.6 . Copper -chrome -boron (CCB) composition — 
This consists of boric acid  (H IBOJ, copper sulphate (CuSO 4.5H 2O) and  sodium or potassium bichromate  
(Na 2Cr2, or.2H 2O or K 2Cr2or.2H 2O) in the  proporti on of I.5: 3: 4; conforming to DUS  2112 -2:2018  
. 
3.1.7 . Copper -8-quirrolinate — 
This is an  organ ometallic compound with typical  composition comprising of 10 percent copper - 8-quinolinate, 
10 percent nickel -2-ethyl  hexanoate and 80 percent inert ingredients.  The preserv ative finds above the ground  
application and is suitable for sapstain and  mold control. It is greenish brown in colour,  odourless and toxic to 
both wood decay fungi  and insects and have low toxicity to humans  and animals.  
4 Methods of Treatment  
Treatment  methods can be divided into traditional/time  tested  methods and chemical methods . Selection  of 
the treatment method depends on many factors:  
State of bamboo - green or dry  
Form - round bamboo, splits or bamboo products.  
End applications - in ground contact , exposed to atmosphere,  
Undercover, structural/non -structural.  
Scale - quantity to be treated and time available.  
Potential causes of decay - biotic (fungus/insects) and abiotic  
(Cracks/weathering  
4.1 Traditional Treatment M ethods  
These are age -old method s which have been practiced in areas where bamboo commonly grows. They are 
simple and cost -effective without the use of supporting equipment. But these methods are not appropriate for DUS 2098:2018  
© UNBS 2018  – All rights reserved  3 
 long-term protection of bamboo  Leaching , smoking and lime washing are ag e-old treatment  methods which 
have been practised where bamboo is grown and  used.  Sometimes, for craft items, protection is also given by 
use of  natural dyes and lacquers, which also lead to value addition  
4.1.1 Leaching  
Leaching helps remove starch and a lso enhances permeability for future  treatment by diffusion and pressure. 
Mechanical properties are affected  for up  to 2- 3 months of water storage.  This method is appropriate for 
treating any quantity of bamboo. It is also  recommended for craft and mat ap plications where pliability is 
required.  
4.1.2. Smoking  
Traditionally, culms are stored over the hearth or fireplace. The moisture  content in smoked culms is thus 
reduced so that biological degradation  cannot take place. Built -up deposits from smoke form a  protective layer  
on the culm. Smoke drying also reduces splitting  
4.1.3. Lime washing  
Lime or whitewashing is mainly used for ornamental effect. Culms and  mats are painted with slaked lime 
(Ca(OH )) which is then transformed 2  into calcium carbonate, CaCO , which inhibits water absorption and 3  
delays fungal attack. Bamboo mats can also be tarred, sprinkled with sand  and whitewashed after drying  
4.1.4. Baking  
Baking on open fire has been used to straighten crooked bamboo culms.  Bamboo is rotated on an open flame 
to prevent localised heating. The  high temperatures destroy the starch and other sugars and also produce  tar 
in the structure. It kills existing infestations if any. Stresses produced  during heating gives dimensional stability 
to the culm. A lower  equilibrium moisture content regime prevents any subsequent fungal  attack if bamboo is 
used in interior application  
4.1.5. Natural Dyes, Varnishes and P aints  
Natural dyes have been used for ages to provide protection and colour to  bamboo products. Dyes are a pplied 
by boiling the material with the  colouring agent, during which the starch is also leached out  
Paints and varnishes are applied on to the bamboo surface to protect it  from dirt and moisture, and to provide 
ornamental effects. They form a  film on the surface of the bamboo. Blistering of the paint/varnish leaves  the 
bamboo surface exposed, and fungal and insect attack may follow. It is  therefore recommended to provide a 
protective coating of preservative  before application of paints and varnishes  
4.2 C hemical Preservation  
Use of chemical preservatives with or without the help of special equipment ensures long -term protection. 
Depending upon the method of treatment, chemicals can impart  short term or long -term protection  
Preservatives are formulations of single compounds or mixtures which protect wood/bamboo against 
biological degradation and discolouration caused by biological attacks. With a few exceptions, chemical 
preservatives are toxic. Selection and application has to be done with care to meet perfo rmance and 
environment requirements. Depending upon the carrier solvents, preservatives are divided into different 
categories  
  
4 © UNBS 2018  – All rights reserved  
  
 
4.2.1 . Water  borne type  
Water -soluble salts are dissolved in water. On treatment, the water  evaporates leaving the salts 
inside  the bamboo. These are further  categorized into non -fixing and fixing types.  
4.2.1.1. Non -fixing type preservative  
These are leachable solutions and their use is restricted to bamboo used in dry conditions and under cover. 
Bamboo treated with these preserv atives should not be exposed to rain or ground contact. Common example: 
Boric acid: Borax & copper sulphate  
4.2.1.2. Fixing  Type preservatives  
These formulations are proportionate mixtures of different salts which interact with each other in the presence 
of bamboo/wood and become chemically fixed. In principle, the degree of fixation and efficacy depends upon 
the nature of the components and their combination. For example, Chromium is responsible for fixation, 
copper is effective against decay fungi and sof t rot and the third compound acts against insect and fungus  
The process of fixation requires some weeks during which the material should be stored under cover. Slow 
fixation is preferred in case of bamboo as it allows diffusion and better distribution of p reserving salts.  
Common example: Copper -Chrome -Boron, Arsenic Pentoxide & Boric  Acid 
4.2.2.  Oily Preservatives: Creosote  
Coal tar and creosote available from coal is a dark brown viscous liquid.  Creosote should be used exclusively 
for pressure processes or  hot and cold  treatment. Being oily, it imparts water repellence to the treated 
material. It  is effective against fungal and insect attack. Due to its dark brown colour  and bad odour, its use is 
restricted to exterior applications, especially in  contact wi th mud/ ground  
4.3. Short -Term Chemical P rotection  
This method of chemical treatment used depends upon whether intermediate protection is required (raw 
material stock) or the material has to be protected over an extended period (finished product ). 
Prophyla ctic treatment is done to prevent immediate attack when the  bamboo is stored for a few days or 
during transportation, using mild  doses of chemicals. Such treatment is also done to intermediate products  like 
slats, slivers and mats which are to be used in t he manufacture of  composite products. Treatment methods 
like spraying, brushing and  dipping give superficial protection, effective for a short period only  
4.3.1 Spraying  
This method is suitable only for large stacks of bamboo stored under  cover in depots.  
1 Stack bamboo horizontally on a raised platform and preferably  sloping ground, and on a polythene sheet.  
2 For large stacks, use an industrial sprayer. For small stacks, a backpack  is sufficient.  
3 Spray chemicals on the top taking special care to cover th e ends and  the cut surfaces (2% solution of boric 
acid: borax . Mix 1 kg of Boric  acid, 1 kg of Borax in 100 litres of water).  
4 Collect the drained solution for reuse  
Note  DUS 2098:2018  
© UNBS 2018  – All rights reserved  5 
 Always use protection during spraying - masks, gloves, goggles, etc  
Spraying causes environmental pollution - only non -toxic chemicals like  boric acid: borax should be used  
Always collect and reuse drained chemicals.  
Spray in the wind direction  
 
4.3.2. Brushing  
It is suitable for small handicraft and household items. 2 -3 coats of  chemical s should be given using a brush. 
The size of the brush will depend  on the material surface to be covered  
4.3.3.  Dipping  
Dipping is used for medium quantities of bamboo/bamboo products.  Dipping is more effective than spraying or 
brushing.  A momentary dip of  30 seconds to a minu te is sufficient to protect the material. The excess material 
should be drained and reused  
4.4. Long -Term Chemical  Protection . 
When  the material is to be stored for long periods, the  preservative needs to penetrate sufficiently to prov ide 
protection over the extended period. The same preservative W e can give short -term or long -term protection 
depending upon the method  of treatment. Long -term protection can be given with or without the use  of 
pressure. The method is determined by the moi sture content in  bamboo, type of preservative and end -use 
4.5. Non -Pressure T reatment  
The methods for non -pressure treatment of bamboo are butt end  treatment, soaking, hot and cold treatment, 
and sap replacement.  Methods like butt end treatment and diffusi on are suitable for green  bamboo only. Hot 
and cold treatment requires air -dry bamboo  
4.5.1 Steeping or Butt End Treatment (Capillary Rise) Method  
Green bamboo up to 1.8 m length can be treated by this method. After removing the branches, bamboos are 
made t o stand vertically in troughs or drums containing solutions of water borne preservatives. Bottom end, up 
to 250 mm is kept immersed and any loss of preservative due to up -take or evaporation is made up daily. The 
top end is kept wet by wrapping with wet co tton cloth. Bamboo is inverted after at least 7 days. The 
preservative is sucked by vessels and is distributed to neighboring cells by diffusion  The time for treatment will 
depend upon the moisture  content and length of the culm  
 4.5.2 . Soaking /Diffusion  
Round bamboo, splits and slivers can be treated by keeping them  submerged in water -borne preservative 
solution. The preservative moves  into the bamboo due to concentration gradient and the cell sap moves out  
due to osmotic pressure. The method of diffusion can be varied by  increasing the concentration of 
preservative to reduce treatment time,  using two salts to increase fixation and filling the lacuna of the culm 
with solution by puncturing the nodes to fasten the diffusion process . The process is slow, requ iring a large 
number of tanks. It is suitable for treating 50 -100 culms a month  
NOTE — The rate of diffusion depends upon the mobility of the ions, The penetration of the ions depends upon the 
moisture content of the green material, its anatomical structur e. the mobility of the diffusing ions, the temperature of the 
solution and the period of immersion in the treating solution  
 
 
  
6 © UNBS 2018  – All rights reserved  
 4.5.3 . Hot and Cold Treatment   
It is based on the principle that on heating, air from the cells will expand  and partially escape.  During cooling a 
slight vacuum is created due to  contraction of the residual air and causes the entry of preservative into the  
cell. Large quantities can be treated at one time  
Note  
Treatment with creosote is most suitable for bamboo used as reinforcemen t in mud/cement  
Viscosity of preservatives like creosote decreases on heating easing penetration.  
Do not use Dichromate containing salts like CCA and CCB as they precipitate on heating  
  
4.5.4 . Sap Replacement Treatment: Modified Boucherie Process  
In this method, the preservative is forced under pressure through the entire length of the culm, so that the sap 
is replaced by the preservative. Up to 5 -6 bamboo culms can be treated at a time. Treatment time for 6 m long 
sections is 3 hrs for interior use and 6 hrs for exterior use  
 
A suitable container is used for keeping the  treatment solution, which shall be of water -soluble  type. The 
container is provided (at the bottom) with  side tubes fitted with stop -cocks and rubber tubes  to which are 
attached the green b amboos with  branches on. [n order to secure leak -proof contact  between the rubber 
tubes and the bamboos, suitable  metallic clalmps or other device should be used. The  tanks is also fitted with 
a screw cap to which is  attached a motor car tyre tube valve (s ee Fig. 1).  
 
The tank is filled with the treating solution to about  two-thirds of the volume and after tightening the cap,  air is 
pumped in through the valve to a pressure of  0.1 to 0.14 N/lmm2 which could be easily measured by  using a 
pen-gauge. Under th is pressure, the treating  liquid forces the sap out of the walls and septa of the  bamboos 
through the open end and takes its (sap’s)  place in course of time. After a few preliminary  experiments, the 
concentration of the treating  solution and the period of treatment can be fixed  to obtain requisite absorption of 
the preservative. The  bamboo is taken off on the completion of the  treatment,  Branches of treated bamboo 
also get treated and are  therefore required to be disposed off carefully as  the same will not degrade naturally 
and are likely to  pose hazard due to presence of toxic chemicals. These  should preferably be burnt in the 
open and ashes  buried underground or be disposed off by any other  suitable method . 
 
 
Note  
• Treated leaves and branches should be bu rnt in the open and ashes disposed carefully.  
• Only safe preservatives containing Boron should be used.  
• Treatment can also be given without pressure. For this a single culm is treated at a time. Treatment without pressure for 
about 5 m of culm takes 6 -7 days.  
 
4.6. Pressure  Treatment  
Pressure methods are suitable for dry bamboo and ensure quick and  uniform penetration of the preservative 
deep inside. The principle of the  process is to force the preservative into the bamboo tissue. This is  achieved 
either  by evacuation of the air inside the culm, or by increased  pressure upon the preservative in a 
pressurized cylinder, or a combination  of both  
Treatment under pressure increases the durability of bamboo. Bamboo  treated by this method will last for 
about 15 years in ground contact and  50 years for building components. Water -borne preservatives and  
sometime creosote are used for the treatment  
Depending upon the pressure schedule, the four different types of  pressure treatment are there and these are 
as follows  
 DUS 2098:2018  
© UNBS 2018  – All rights reserved  7 
 4.6.1.  Vacuum  Process  
The culm is first evacuated by creating a vacuum to partly remove air  which may restrict entry of preservative 
solution due to air bubbles. The  solution floods into the cylinder and forces into the culm on release to  normal 
pressure . Another cycle of vacuum is repeated to improve  penetration and preservative loading  
 
4.6.2.  Full cell Process  
This is similar to the vacuum process in the first stage where the culm is evacuated. In the second stage the 
preservative is pumped into the cu lm under a pressure of 5 -15 bar for some hours. The purpose is to fill the 
cell lumens completely with preservative solution. At the final stage, a vacuum  
is again created for 10 minutes after draining the preservative and to eliminate bleeding by removing  excess 
material  
This schedule is used for treating of bamboo culms to be used for  structural applications, where high retention 
and penetration has to be  ensured. The preservative in cell lumens is subsequently soaked into  adjacent 
fibres and parenchyma c ells 
 
4.6.3. Empty Cell Process  
This process is used where low retention but complete penetration is  required. The preservative forms a 
coating on the cells and does not fill  the lumen  
Cost of equipment for this method is higher than for full cell pressure  and requires more operational skill  
 
4.6.4.  Fast Fluctuating Pressure Process  
Initially a vacuum is created followed by flooding of preservative at 5 -15 bars. This pressure is maintained for 
a few minutes and then abruptly  dropped to atmospheric level. Th e pressure is again raised and dropped.  
Many such pressure cycles are administered and with each cycle the  pressure holding period is reduced. 
Vacuum in the final stage prevent  dripping. This method is adopted for green bamboo when the moisture  
content is more than 60%.  
Higher concentration salts (8 -10% CCA or 5 -6% boron salts) are used as  the solution becomes diluted with 
sap from the culm.  Some important points that must be kept in mind for establishment of  pressure treatment 
facility  
Since the capacity o f pressure treatment plants would be higher  than non -pressure processes, there must be 
a steady demand for  treated material. Unless capacity of the facility is fully utilised, cost  of treated culms 
would not be economical for most commercial  purposes  
The c ulms have to be dry with about 20% moisture to allow free passage  of the preservative  
5 Choice of Preservative and M ethod  of Treatment  
The choice of the preservative and the method  of treatment depend upon the use to which the treated  material 
is put.  
The recommended practice with regard to  preservative, their concentration, requisite absorption  and 
method of treatment of bamboos and canes for  diverse purposes, is given in Table 1.  
6 Samples  
6.1 Representative samples for testing of  preservatives shall be c ut from the treated cane or  bamboo for the 
purpose of chemical analysis. The  mass of the sample shall be about 50 g for cane and  about 100 g for 
bamboos, for every 100 kg of cane or  bamboo treated.  
  
8 © UNBS 2018  – All rights reserved  
 6.2 The sample obtained in 6.1 shall be powdered  either b y a hand file or by means of  a suitable powdering  
machine or converted into small chips (about 10 mm  long, 2 mm wide and 1 mm thick) by using a suitable  
knife. The powder or chips thus prepared shall be  thoroughly mixed and a liquid of 10 to 20 g taken for  
chemical analysis.  
7 Testing of Preservative in T reated  Material  
7.1 Determination of Absorption of the Preservative   
The net absorption of the preservative chemicals  in bamboo and cane shall be determined by chemical  
analysis of treated material and shal l be compared  with the figures obtained from the weight of the  material 
before and after treatment, wherever possible.  The final sample obtained in 6.2 shall be used for the  analysis . 
 
Table 1 Recommended Preservatives, Their Concentration and Absorption , and the Method 
of Treatment  of Bamboo and Cane Used for Diverse Purposes   
 
 
  
 
 Diverse (non -
structural) uses 
of treated 
bamboo and 
canes  Recommende
d 
preservative  Concentration of 
preservative,  
percent  Absorption of 
preservative  
(kg/m3) Methods of treat ment   
i Chicks, jafri, mats 
exposed to weather  d 6 5 Diffusion process, FFP process   
 a) Green split 
bamboo  
(split. sliver)   e, f 8 8 Diffusion process, FFP process   
       
 b). Dry bamboo 
(spilt, silver)  d 4 5 Vacuum/pressure process.  
steeping   
    e,f 6 8 Vacuum/pressure process.  
steeping   
    b 4 percent as  
copper (for  
copper  0.4 as copper  Soaking /brush   DUS 2098:2018  
© UNBS 2018  – All rights reserved  9 
 napthanate/  abietate)  
   6 percent as  
zinc ( for zinc  
napthanateslabietate)  0.6 as zinc  Soaking /brush   
ii Furniture exposed to 
the 
weather 
(components):       
 
a) Green bamboo 
(round)and cane, for  
legs and arms  d 4 to 6  5 Modified Boucherie process.  
diffusion process, FFP process   
       e,f 6 to 8  8  Modified Boucherie process.  
diffusion process, FFP process   
 b)  Green bamboo 
(spilt)  
and canes, for parts 
other than those in 
(a). d  4 to 6  5 Diffusion process, FFP process,  
steeping   
         e ,f 6 to 8  8 Diffusion process, FFP process,  
steeping   
 c) Dry bamboo 
(round or split) and 
cane, for  legs and 
arms  d  
4 to 6  5 Vacuum/pressure proc ess. 
Soaking   
        e ,f 6 to 8  8 Vacuum/pressure process.  
Soaking   
  b 4 percent as  
copper (for  
copper  
napthenate/abietate)  0.4 as .copper  Soaking/brush   
   6 percent as  
zinc (for zinc  
napthenate/abietate)  0.6 as zinc  Soaking/brush   
iii Furniture fo r interior  
(components) 
including  
chicks. mats        
 a) Green bamboo 
and cane (round, 
split, sliver  c, e,f  4 to 6  5  Modified Boucherie process, 
diffusion process, FFP process. 
steeping   
 b) Dry bamboo and 
cane  
(round, split, sliver)        c, e ,f  4 5 Steeping, vacuum/pressure  
process   
  b 4 percent as  
copper (for  
copper  
napthenate/  
abietate  0.4 as copper  Soaking/brush   
   6 percent as  
zinc (for zinc  
napthenate/  
abietate  0.6 as zinc  Soaking/brush   
iv Basketware:       
 a) Agriculture use. 
other  
than f ood stuff       
 Green bamboo (split,  
slivers)  e, f, g  4 to6  5 Diffusion process, FFP process   
 Dry bamboo (split, 
slivers  e, f, g  
 2 to 4  5 Steeping, hot and cold, vacuum/  
pressure process   
   b 2 percent as copper 
(for copper  
napthenate/abietate  0.2 as copper  
 Soaking/brush    
10 © UNBS 2018  – All rights reserved  
  
   3 percent as zinc (for 
zinc napthenate/  
abietate)  0.3 as zinc  
 Soaking/brush   
  a 30:70  -------  Hot and cold, bot soaking   
 b) Food stuff. 
including  
fresh fruit, 
vegetable;,  
tea-leave;, etc       
 Green bamboo (split,  
slivers c 5 4 Diffusion process, FFP process   
 Dry bamboo (split,  
slivers)  c 5 4 Steeping, vacuum/pressure  
process   
  g 2 percent as  
copper  4 Momentary dip, brush   
v Finished/semi -
finished  
products  
Mats for building 
boards:       
 UF bonded boards  b 1 -------- Steeping/mix in glue   
 PF bonded boards  Lindane based  
formulations  -----------  2 kg/100 kg  
glue Glue line poisoning   
vi Handicrafts  b 1 percent (as  
copper/zinc)  ---------  Momentary dip   
       
 
 
7.2 Determination of Presence of the Preservative  
The penetration of the following preservatives in the treated bamboo and cane may be tested and by the 
visual colour reaction method given in annex A  
a) Copper -chrome -arsenic (CCA) composition  
b) Acid-copper -chrome (ACC) composition  
c) Copper -chrome -boron (CCB) comp osition, and  
d) Boric acid and borax.  
 
7.2.1  Preservatives other than those referred to  in 7.2. do not give definite colour reactions.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DUS 2098:2018  
© UNBS 2018  – All rights reserved  11 
  
 
 
 
 
 
 
 
 
 
ANNEX A  
          (Normative)  
 
Method for the determination of presence of preservatives by col our reaction  
 
A-1 copper -chrome -arsenic composition, acid -coppe r-chrome composition and copper -chrome -boron 
composition  
 
A-1.l Copper  
A-1.1.1 Preparation of Reagent  Dissolve 0.5 g of chrome azurols concentrate and  5.0 g sodium 
acetate in 80 ml water and di lute the  solution to 100 ml.  
 
A-1.1.2 Test Spray the solution so obtained in A-1.l.l or dip into  it, a reasonably dry boring or cross -
section of the  bamboo or cane to be tested.  
 
A.l. 1.3 Reaction  
The material treated with the preservative quickly  turns  deep blue in colour.  
 
A-1.2 Arsenic  
A-1.2. 1 Preparation of Reagents  
A-1 .2.1.1 Solution 1— Dissolve 3.5 g ammonium  molybdate in 90 ml, distilled water, and add 9 ml 
cane  boric acid.  
A-1 .2.1.2 Solution 2 — Dissolve 0.07 g benzidine  dihydrochloride in 10 ml cane acetic acid and add  
the solution to 90 ml distilled water.  
A-1.2. 1.3 Solution 3 — Dissolve 30 g stannous chloride  in 100 ml of 50 percent hydrochloric acid.  
A-1.2.2 Test First apply solution 1 on the cross -section or boring  by dipping or pouring. The  entire 
surface must be  saturated. After 2 rein, shake off the excess solution  and allow to dry for about 1 
min. Next, apply Solution  2 in the same manner as Solution 1. Apply Solution 3  by pouring the 
solution on across -section, beginning  at the untreated  part. 
 
A-1 .2.3 Reaction  The entire wood surface will immediately turn  bluish. It is necessary to wait for 
several minutes  for the reaction to bring about the maximum colour  contrast.  
 
A-2 BORIC ACID AND BORAX AND COPPER -CHROME -BORON COMPOSITION  
 
A-2, 1 Preparation of Reagents  
A-2. 1.1 Alcoholic Extract of Turmeric Powder  Reflux 2 g of turmeric powder with 100 ml of 95 
percent  alcohol for 1 h; cool it and filter.  
  
12 © UNBS 2018  – All rights reserved  
 A-2. 1.2 Extract of Salicy!ic Acid and Hydrochloric  Acid Saturate with salicylic acid a mixtu re of 80 
ml of distilled  water and 20 ml of 30 percent hydrochloric acid.  
 
A-2.2 Test  
Apply the alcoholic exbact of turmeric powder obtained  in A-2.1.1 on a reasonably dry surface of the 
material  to be tested. Allow the surface to dry for a few minutes  and then apply the extract obtained 
in A-2.1.2.  
 
A-2.3 Reaction  
The treated surface develops red colour.   DUS 2098:2018  
© UNBS 2018  – All rights reserved  13 
 Bibliography  
[1] IS 1902 preservation of bamboo and cane for non -structural purposes —code of practice  
 DUS 2098 :2018  
© UNBS 2018  – All rights reserved  15 
 Certification marking  
Products that conform to U ganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used  only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that th e goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for c onformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
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