THAI AGRICULTURAL STANDARD  
TAS 1004  - XXXX  
 
 
 
CODE OF PRACTICE FOR SULPHUR DIOXIDE  
FUMIGATION OF  FRESH FRUITS  
 
National Bureau of Agricultural Commodity and Food Standards  
Ministry of Agriculture and Cooperatives  
ICS   67.020.                                    ISBN  XXX -XXX -XXX -XXX -X  
 UNOFFICAL TRANSLATION   
THAI AGRICULTURAL STANDARD  
 TAS 1004 -XXXX  
 
 
 
CODE OF PRACTICE F OR SULPHUR DIOXIDE 
FUMIGATION OF  FRESH FRUITS  
National Bureau of Agricultural Commodity and Food Standards  
Ministry of Agriculture and Cooperatives  
50 Phaholyothin Road, Ladyao, Chatuchak,  Bangkok 10 900 
Telephone ( 662) 561 2277   Fax. (662) 561 3357  
www.acfs.go.th  
Publi shed in the Royal Gazette Vol ……  Section……..  Special ,   
Dated       (2) 
 
  Technical Committee on the Elaboration of the Thai Agricultural Standard on  
Good Manufacturing Practices for Sulphur  Dioxide Fumigation on Fresh Longans 
 
1.  Ms. Surmsuk Salakpetch                   Chairperson  
  Department of Agriculture 
2.  Ms.Patcharawadee Suwanathada       Member  
  Department of Pollution Control, 
  Ministry of National Resource and Environmental 
3.   Mrs.Sumalee Dachoponchai       Member  
   Department of Industrial Work s, Ministry of Industry 
4.   Ms. Penrapee Thong-In        Member  
   Department of Agricultural  Extension  
5.   Ms. Chitra Settaudom        Member 
Food and Drug Administrati on, Ministry of Health 
6.   Mr. Kriangkai Supatosa        Member  
   Plant Standard and Certification O ffice, Department of Agriculture 
7.  Mr. Uthai Noppakoonrong       Member  
  Office of Agricultural Research  and Development Region 1, 
  Department of Agriculture 
8. Assistant Professor Jakra phong Phimphimol     Member  
  Faculty of Engineering and Ag ro-Industry, Maejo University 
9.  Assistant Professor Somchai Jomduang      Member 
  Faculty of Agro-Industry, Chiang Mai University  
10.  Mr. Sunchai Puranachaikere       Member  
  Thai Fresh Fruit Traders and Exporters Association 
11.  Mrs. Suchin Srikongsri         Member  
  Verification and Laborator y Analysis Association 
12.  Representative of Chiangmai Provinc ial Administrative Organization  Member 
13. Mrs. Bussara Chankaewmanee       Member 
 Expert on Agricultural Commodity Quality 
14.  Mrs. Malee Premmanee        Member  
 Expert on Longan Production  
15. Ms. Nalinthip Peanee         Member and Secretary  
 National Bureau of Agricultural Commodity    and Food Standards  (3) 
 
 
Fresh fruits fumigation with sulphur dioxide  is one of the processes for post harvest 
management to extend the shelf life of pr oduce for their freshness and quality required. 
Improper fumigation of fresh fruits with sulphur  dioxide will cause excessive sulphur dioxide 
leftover and affect consumer health. Th e Joint FAO/WHO Food Standards Programme 
(CODEX) has established Maximum Level of su lphur dioxide for fresh fruits. However, 
several countries have also set the Maximum Le vels differently resulting in negative effects 
on international trade. The control of fumigation process with sulphur dioxide is thus 
extremely important, therefore, the Agricultu ral Standards Committee deems it necessary to 
establish the Code of Practice for sulphur dioxi de fumigation of fresh fruits in order to 
prevent excessive residue in the produce against the national regulation or trading partners 
requirements to be practiced by the relevant stakeholders. 
This standard is based on the following document:  
TAS 1002-2010. Good Manufacturing Practices fo r Sulphur Dioxide Fumigation on Fresh 
Longans. National Bureau of Agricultural Commodity and Food Standards.  
 
 TAS  1004 -XXX X 
(Final Draft)  Thai Agricultural Standard:  Code of Practice for Sulphur Dioxide Fumigation of Fresh Fruits  UNOFFICAL TRANSLATION  
 
(Final Draft)  
THAI AGRICULTURAL STANDAR D 
CODE OF PRACTICE FOR  SULPHUR DIOXIDE  
FUMIGATION OF FRESH FRUITS  
 
1. SCOPE  
This standard establishes code of practice for sulphur  dioxide fumigation of fresh fruits so as 
to obtain fresh fruits  which are safe and of  quality suitable for consumption and not  to cause 
any impact to the environment . 
2. DEFINITIONS  
For the purpose of this standard : 
2.1 Sulphur dioxide  means gas of the chemical formula SO 2 obtained from the burning of 
sulphur or other methods. The gas is colourless, inflammable and pungent  with antimicrobial 
and antibrowning  properties . 
2.2 Fumigation  means a process where sulphur dioxide application is treated to the produce 
by the control of concentrations and specified time schedules . 
3. REQUIREMENT S 
3.1 The processes of sulphur dioxide fumigation for fresh produce in a chamber shall be  
practiced as shown in Table 1 . 
3.2 Any fumigation process that  does not use the chamber for treatment, whereas some 
requirements of the Table 1 may not  be fulfill ed, the crit eria and conditions for assessment 
stipulated by the National Bureau of Agricultural Commodity and Food Standards shall 
comply to thereof . 
 
Table 1 Requirements for Sulphur Dioxide Fumigation of Fresh Fruits  
 
 
Items  Requirements  
1. Establishment  
(1) Location  
  
1.1 Locate in the area that does not cause any contamination 
to the quality of produce and consumer  safety without any 
impact to the environment.  If there is any risk, preventive 
measure shall be in place . 
1.2 Site of the establishment shall be permitted  according to  
relevant laws and regulations .  
TAS  1004 -XXXX               2 
(Final Draft)  Thai Agricultural Standard:  Code of Practice for Sulphur Dioxide Fumigation of Fresh Fruits  Items  Requirements  
(2) Working areas  1.3 Sufficient space for the operations covering raw material 
receiving, fumigation process and post handling of treated 
produce shall be in place.  
(3) Fumigation chamber  
 
 1.4 Availability of trea tment chamber with sturdy and secure 
structure  
1.5 Surfaces of w alls and floor of the chamber shall be 
smooth and free from cracks. Materials used shall be resistant 
to corrosion, impervious  to gas  and easy to clean.  
1.6 The chamber shall be able to prevent l eaking of gas, 
particularly at the door and seams or joints. In addition, 
suitable materials which are also resistant to corrosion shall be 
used.  
1.7 Lighting shall be installed in the proper position provided 
with adequate light for work and ready for each  use.  
1.8 Availability of observatory  window to monitor conditions 
inside the chamber.  
1.9 Availability of air circulation system to disperse the gas 
throughout the chamber.   
(4) Gas recapture system  1.10 Availability of effective gas recapture system.  
1.11 Gas recapture system shall be inspected for its 
effectiveness at least once a year.  
(5) Tools and equipment  1.12 Tools and equipment used for the fumigation shall be in 
good  condition and effective.  
1.13 Suitable weighing scale for sulphur and/or sulphur 
dioxide shall be accurate and precise  
1.14 Availability of precise timer .  
(6) Occupational  safety  for 
worker s 
 1.15 Tools and equipment shall be in good working condition s 
and in sufficient amoun t for worker s. Safety signs sh all also be 
present ed at the workplac e.  
2. Operation control  
(1) Raw material s  
  
2.1 Inspect the incoming produce according to  the 
establishment specifications . 
2.2 inspect the materials used for fumigation such as sulphur 
and sulphur dioxide according to their specifications . 
(2) Conta iners  for fresh fruits  
 2.3 Containers shall be clean, strong and suitable for the gas 
to pass through and allow the fruits to be exposed to the gas 
during the fumigation process . 
(3) Sulphur dioxide fumigation  
process  
 2.4 Availability of the results on the validation or verification 
of method of sulphur dioxide fumigation of the chamber. Such 
results shall include the efficacy inspections of fumigation in 
the empty chamber and at least one load of produce at the 
beginning of the operation or changing met hod of fumigation. 
The leftover sulphur dioxide residue in fresh fruits shall not 
exceed the Maximum Level of national or trading partners 
regulations . 
TAS  1004 -XXXX  
(Final Draft)  Thai Agricultural Standard:  Code of Practice for Sulphur Dioxide Fumigation of Fresh Fru its 3 
Items  Requirements  
 2.5 Availability of clear and correct procedures for the 
operations such as work flow chart, table sho wing amount of 
sulphur or sulphur dioxide usage, duration of treatments in 
relation with the volume of produce, produce arrangement and 
possible number of containers in the chamber including periods 
of storage and  transportation.  
 2.6 Availability of oper ator wh o has experience and  skill in 
the fumigation process.  
 2.7 The cham ber and equipment shall be inspect ed for their 
appropriate conditions , cleanliness  and readiness for use such 
as door seal, circulating fan/blower , light ing, sulphur burner, 
exhaus t fan/blower , concentration of  lime solution (calcium 
hydroxide) , spray  nozzle s, weigh ing scale and timer . 
2.8 Control of prepared produce for fumigation shall be i n 
accordance with the methods  in 2.4 . 
2.9 Control of sulphur or su lphur dioxide usage sh all be i n 
accordance with the methods  in 2.4 .  
2.10 During the fumigation process, control and monitor the 
fumigation in accordance with the methods  in 2.4 .  
(4) Post fumigation  handling  
  2.11 When the fumigation  process  is completed and prior to 
openi ng the chamber, the leftover circul ation gas  in the 
chamber shall be released  appropriately and effectively.   
2.12 The leftover circulation gas from the chamber referred to 
in 2.11 shall be diverted and purged into the effectively tested 
gas recapture unit and monitor  the operation system regularly .  
2.13 Containers of treated produce rested outside the chamber 
shall be blown to release  the remaining sulphur dioxide to 
prevent residue in fresh produce over the Maximum L evel.  
2.14 Treated produce sha ll be sampled for sulphur dioxide 
residue testing at least once a year.  
(5) Storage  2.15 Store treated produce  or treated produce awaiting  
transport in an appropriate area.   
(6) Waste management  
 2.16  Waste materials or debris such as leaves, treated w aste 
water from gas recapture unit and waste from lime solution 
shall be removed from the operation areas and properly 
disposed . 
3. Training  
 3. Train or put operators on the job training to gain 
knowledge and skill to their assigned works including 
refreshment training and updating their performance at least 
once a year . TAS  1004 -XXXX               4 
(Final Draft)  Thai Agricultural Standard:  Code of Practice for Sulphur Dioxide Fumigation of Fresh Fruits  Items  Requirements  
4. Documents and record 
keeping  
 4.1 Availability of documents and records of work operations 
including sale, distribution and storage , for the purposes 
of assessment and traceability such as:  
 - inspection results of validation  or verification  method 
of sulphur dioxide fumigation;  
 - test results of sulphur dioxide residue in treated 
produce;  
 - receiving of raw materials, storage, and sale/  distribution ; 
 - control/monitor of sulph ur dioxide fumigation process; 
and 
 - training or on the job training records of operators and  
the person who controls the fumigation process  
4.2 Documents and records shall be kept for at least 2 years .