PUBLIC REVIEW DRAFTDGS  1347 -1 
 1 Introduction  
 
Wood has since been used for charcoal production in the form of lumps and briquette . 
Conversion of wood into charc oal and charcoal based products  provide s income generating 
options for farmers and communities.  
Wood  charcoal is produced by pyrolysis  (i.e. the thermal decomposition of wood  biomass 
carried out in high temperature with no or limited supply of air (oxygen) ). In addition  to energy 
applications  other uses include : 
 
1. Purification and adsorption (drinking water, air filters, gas masks)  
2. Daily health care   
3. Deodorizer  
4. Building interior decoration   
5. Industrial  
6. Soil improvement   
 
  PUBLIC REVIEW DRAFTDGS  1347 -1 
 2  
 
DRAFT GHANA STANDARD             DGS 1347 -1 
 
 
Carbonization : Part 1:  - Code of Practice for wood ( lump and briquette ) Charcoal  
Manufactur ing.  
 
 
1.0    Scope  
 
This standard describes the acceptable minimum requirements for exercising total quality 
control in wood  charcoal production  plants and adherence necessary in order to assure quality 
and reliability of wood  charcoal and its  products .  
 
2.0 Normative R eferences  
 
The following standards contain provisions , which though reference in this text, constitut e 
provisions of this standard. All standards are subject to revision, and parties to agreements 
based on this standard are encouraged to investigate the possibility of applying the most 
recent editions of the standards indicated below : 
 
 
2.1   DGS 1346 -1 - General Requirements for Charcoal - Part 1: wood charcoal.   
2.2 DGS  1347 -2 - Carbonization: Part 2: - Code of Practice for bamboo charcoal 
manufacturing.  
2.3   GS ISO 7010: Graphical symbols — Safety colours and safety signs — Registered safety 
signs . 
2.4   GS ISO 23601: Safety Identification — Escape and Evacuation Plan Signs  
2.5   GS ISO/TS 20559: Graphical Symbols — Safety Colours and Safety Signs — Guidance 
for the Development and Use of A Safety Signing System . 
2.6   GS ISO 3864 -1:  Graphical Symbols — Safety Colours and Safety Signs — Part 1: 
Design Principles for Safety Signs and Safety Markings . 
2.7   ISO 3864 -2:  Graph ical Symbols — Safety Colours and S afety Signs — Part 2: Design 
Principles for Product Safety Labels . 
2.8   ISO 3864 -3: Graphical symbols — Safety colours and safety signs Part 3: Design 
principles for graphical symbols for use in safety signs . 
 
 
3.0       Terms and D efinitions  
 
3.1 
accredited laboratory  
laboratory  that has ISO/IEC 17025 accreditation and can perform wood charcoal tests.  PUBLIC REVIEW DRAFTDGS  1347 -1 
 3  
3.2 
kiln 
a chamber used for carbonization of wood  and in which the temperature and humidity of the 
circulating air can be suitably controlled.  
  
3.3 
plant  
refers to the machinery, equipment or apparatus used for  charcoal production . 
 
3.4 
procedures  
established steps in carbonizing wood . 
 
3.5 
quality control  
a system of maintaining standards in manufactured products by testing a sample of the 
output against the specification  and correct deviations . 
 
 
4.0 General Requirements  
 
4.1  Quality control is the responsibility of top management of the wood  charcoal  company. 
However, an adequately trained member of staff shall be charged with the responsibility for 
following  documented quality control procedures.  
 
4.2 These documented procedu res shall require surveillance and control, from purchase 
of the basic raw material through all phases of manufacture and processing until delivery to 
the customer.  
 
4.3 Records shall be kept covering raw material sources, seasoning, and results of 
carboni zation . Records for each lot of material processed shall carry an identification number 
and show the date of carbonization . These records shall become a part of the company’s 
permanent file.  
 
4.4 The company shall provide laboratory reports on tests as  well as other test reports that 
may be agreed upon with the customer. The laboratory test reports shall be from the GSA or 
any accredited laboratory.  The laboratory shall preferably be an ISO/IEC 17025 accredited 
laboratory.  
 
 
4.5 When it becomes evident that any phase of production does not comply with the 
requirements of relevant National Standards  and customer’s specification, the Quality Control 
designee shall notify management and corrective measures shall be taken . 
 
4.6 The Quality Control designee shall not release any material for delivery to the 
customer or for inspection  until the person  is satis fied that the material complies with relevant 
National Standards . 
 
 
  PUBLIC REVIEW DRAFTDGS  1347 -1 
 4 5.0 Material  Pre-Carbonization  Quality  Control  
 
5.1 Plant Quality Control designee shall determine that all wood  materials have been 
stored in accordance with the relevant National Standards  and good manufacturing practice 
while under plant control and prior to preparation  for carbonization . 
 
5.2 Plant Quality Control shall determine that all wood  species  comply with  the relevant 
National Product Standards , and the customer’s specifications , if any . 
 
 
6.0 Plant Gauges and Recorders  
 
6.1 Plants shall be equipped with pressure and temperature recorders  during each cycle 
of carbonization . Plant s shall also be equipped with pressure and temperature  gauges  for 
checking the accuracy of the recorders.  
 
6.2 All recorders, and gauges , including thermometers,  shall be calibrated and certified for 
accuracy by a n accredited body  at the time of installation , and annually thereafter. Whenever 
there is evidence of malfunction, which cannot be corrected by simple adjustment, the 
instrument or gauge shall be promptly repaired or replaced , re-calibrated  and re -certified for 
accuracy.  
 
 
6.3 Recording instruments shall be compared duri ng different stages of carbonization  with 
the indicating gauges  and thermometers.  The recorder reading shall be within the tolerances 
given below.  
 
a) Thermometers – Recording instrument and the thermometer shall agree within 
2degree s Celsius.  
 
b) Gauges  – The recording instrument and the pressure gauge shall agree within 0,35 
bar (35 kPa) . 
 
6.4 Calibration of thermometers and gauges  as required under clause 6 .2 shall be made 
as follows:  
 
a) Thermometers  – Compare with thermometer of known accuracy and allow a variation 
not exceeding 1 degree Celsius (10C). 
 
b) Pressure Gauges  – Compare with standard test gauge or suitable gauge testing 
device and allow a variation not exceeding 0 ,2 bar (20 kPa) . 
 
 
7.0  Kiln 
 
Plant Quality Control designee shall  determine that the kiln  used in the carbonization  conforms 
to the r equirements  for the type as approved by the regulator . (Refer to annex A for  kiln 
performance characteristics ). 
  PUBLIC REVIEW DRAFTDGS  1347 -1 
 5 8.0       Occupational Health and Safety  
It is the responsibility of the plant management or the designee for the quality control to 
establish health and safety guidelines for safe operation of the kiln and other processes.  
8.1   Provision of signages  
Management designee in charge of quality and manufacture, shall provide appropriate health 
and safety signages at entry to the plant and within the plant area.  
All applicable safety signs shall comply with GS ISO 7010,  GS ISO 23601, GS ISO/TS 20559 
and GS ISO 3864: 1 -3. 
8.2   Training on occupational h ealth and safety  
It is the responsibility of Management to train, retrain and also establish a predetermined 
program for drills on health and safety.  
8.3   Near -accident prevention  
Top management or its designee shall put in place health and safety procedure and work 
instructions to avoid near -accident situations.  
All staff shall be trained to identify near -accident hazards and report it to management as and 
when it occurs.  
8.4   Provision of fire extinguishers and manual wate r sprinklers  
Top management shall provide fire extinguishers at vantage points, outside and inside of the 
plant (company).  
8.5   Safety apparel  
Top management or its designee shall provide workers with the appropriate Personal 
Protective Equipment such as  eye goggles, hand gloves, clothes and boots and also to ensure 
that the safety apparel are worn all the time.  
8.6   Climbing ladders  
Top management or its designee shall provide appropriate ladders for safe climbing into and 
out of the kilns.  
 
9.0   Carbonization  
 
9.1 The carbonisation , unless otherwise specified, shall conform to Annex B  of DGS 1347 -
2. Plant Quality Control designee shall maintain re cords on the cycles of carbonization and 
the Kiln  gauge readings.  
 
9.2 Care ful observation during carbonization  shall be made of temperature s and 
pressures and their duration to make sure that they are within the specified limits.  
 PUBLIC REVIEW DRAFTDGS  1347 -1 
 6  
10. Results of Carbonization  
 
10.1 After carbonization , an examina tion shall be made of the charcoal  for any defects .  All 
partially ca rbonized  wood  that cannot be re cycled for re -carbonization shall be segregated . 
 
10.2     Plant Quality Control designee shall inspect each carbonized wood  (charcoal ), perform 
checks on the net weights of th e charcoal, partially  carbonized wood  and ash content  charge 
to determine conformance with the kiln efficiency  specified in the National Standards (clause 
A.1.1  of Annex A and clause 6 of DGS 1346 -1 General Requirements for Charcoal - Part 1: 
wood charcoal)   
 
Plant Quality Control designee shall also determine in each and every efficiency  by the 
appropriate method, that the kiln efficiency  conforms to the specification in the relevant 
National Standar ds (Annex  A). 
 
 
11. Reports  
 
The Wood  carbonization  company shall furnish the customer or his representative with a 
certificate of compliance or such repor t on the charcoal . 
 
See Annex B for the sample test report format.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  PUBLIC REVIEW DRAFTDGS  1347 -1 
 7 ANNEX A  
(NORMATIVE ) 
 
A.1 Kiln Performance Characteristics  
A.1.1 Efficiency  
1. A minimum yield efficiency of 60%  
A.1.2 Emissions  
1. Greenhouse gas emissions  
• CO (m g/m3)  - (100 max)  
• CH 4 - (7% max)  
• Sulphur Dioxide (mg/Nm3 ) – (200 max)  
• Oxides of Nitrogen (mg/Nm3 ) – (200 max)  
• particulate matter (PM 2.5) – ( 50 max)  
A.1.3 Other  by-products  
1. Wood vinegar and tar  
A.1.4 Usage  
1. Ease of operation and maintenance  
2. Safe to use  
 
A.2 Design  Requirements  
A.2.1 Material  
Material used for kiln construction or fabrication shall be from the following:  
Clay - natural clay  
Bricks – (clay burnt bricks, clay with refractory bricks)  
Metal – (stainless steel, mild steel)  
A.2.2 Thermal insulation –  
The exothermic temperature of  the kiln shall  not exceed 60 degree  Celsius . The following 
materials shall be used.   
• Clay - natural clay , stabilized clay Brick  PUBLIC REVIEW DRAFTDGS  1347 -1 
 8 • Ceramic fibres  
• Refractory bricks  
A.2.3 Vents  
The kiln shall be fitted with the following:  
Inlet vents  
Outlet vents (chimney)  
A.2.4 Trap  
The kiln shall be fitted with a trap to capture emission  (particulate matter and gases) for 
possible conversion to wood vinegar and tar.  
 
A.3 Kiln Conversion E fficiency (E kc) 
The dry kiln conversion efficiency shall be estimated using the following expression:  
𝐸𝑘𝑐=𝑀𝑎𝑠𝑠  𝑜𝑓 𝑐ℎ𝑎𝑟𝑐𝑜𝑎𝑙 (𝐶𝑚)
𝑀𝑎𝑠𝑠  𝑜𝑓 𝑑𝑟𝑦 𝑤𝑜𝑜𝑑 (𝐷𝑚)𝑥100 
Ekc – dry kiln conversion efficiency  
Cm – mass of wood after carbonization  in kg  
Dm - mass of dry wood in kg  
The pre dried wood shall have a maximum moisture content of 30%.  
 
Note:  The minimum recommended kiln conversion efficiency shall be 60%  
 
 
 
 
 
 
 
 
 
 
  PUBLIC REVIEW DRAFTDGS  1347 -1 
 9 ANNEX B  
(INFORMATIVE)  
FACTORY TEST REPORT SAMPLE  
 
FACTORY REPORT  
 
FACTORY NAME: …………………………………………………………………………… ……….  
 
 
LOCATIO N: 
a. TOWN  …………………………………………………… ………………………………… …… 
 
b. DIGITAL ADDRESS: ……………………………………………………………………….. ..... 
 
CHARGE NUMBER: ………………………………………………………………………… ……….  
 
CHARGE LOAD (kg): …………………………………………………………………………… …… 
 
TYPE OF CHARCOAL: ………………………………………………………....................... ..........  
 
PRODUCTION OFFLOAD (kg): ……………………………………………………… ……………..  
 
QUANTITY IN A BATCH ( kg): ……………………………………………………………………….  
  
BATCH OR LOT:  ………………… ……………………………………………………….... .............  
 
DATES/PERIOD OF PRODUCTION: ……………………………………………………… …........  
 
TEST DATE: …………………………………………………………………………………… ……...  
 
NAME OF RESPONSIBLE OFFICER: ……………………………………………………… ……..  
 
SIGNATURE/DATES ………………………………………………………………………… ………  
VERIFICATION………………………………………………………………………………… ……...  
Note: charge number shall be taken per kiln.  
 
 
 
 PUBLIC REVIEW DRAFTDGS  1347 -1 
 10  
 
 
BIBLIOGRAPHY  
 
GS 146 -1 Code of practice for wood treatment plant - part 1: Quality control procedures for 
wood treatment plant.