Annex 9. Fumigation
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Annex 9. Fumigation

 1 General

1.1 Fumigation is a method of pest control that completely fills an area with gaseous pesticides - or fumigants - to suffocate or poison the pests within. It is utilized for control of pests in buildings (structural fumigation), soil, grain, and produce, and is also used during processing of goods to be imported or exported to prevent transfer of exotic organisms. This method also affects the structure itself, affecting pests that inhabit the physical structure, such as woodborers and drywood termites.

1.2 Timber products used for dunnage can be treated by fumigation under the requirements of the International Standards for Phytosanitary Measures, No. 15 (ISPM 15)footnote. Some shippers believe, incorrectly, that they can achieve this by throwing in a fumigation bomb just before the CTU doors are closed. This, however, is not permitted under ISPM 15 and does not achieve the required level of treatment.

1.3 Fumigated CTUs containing no other dangerous goods are subject to a number of provisions of dangerous goods regulations, such as those included in this annexfootnote.

1.4 When the fumigated CTU is packed with dangerous goods in addition to fumigant, any provision of the dangerous goods regulations (including placarding, marking and documentation) applies in addition to the provisions of this annex.

1.5 Only CTUs that can be closed in such a way that the escape of gas is reduced to a minimum should be used for the transport of cargo under fumigation.

 2 Training

Persons engaged in the handling of fumigated CTUs should be trained commensurate with their responsibilities.

 3 Marking and placarding

3.1 A fumigated CTU should be marked with a warning mark (see figure 9.1) affixed at each access point in a location where it will be easily seen by persons opening or entering the CTU. This mark should remain on the CTU until the following provisions have been met:

  • The fumigated CTU has been ventilated to remove harmful concentrations of fumigant gas; and
  • The fumigated goods or materials have been unpacked.

3.2 The fumigation warning mark should comply with the relevant dangerous goods regulations. Below is the fumigation warning mark as shown in the 18th revised edition of the United Nations Recommendations on the Transport of Dangerous Goods, Model Regulations.

Figure 9.1 Fumigation warning mark

 4 Ventilation

4.1 After the fumigant has performed its function it can be ventilated before it is transported if required. When the fumigated CTU has been completely ventilated either by opening the doors of the CTU or by mechanical ventilation after fumigation, the date of ventilation should be marked on the fumigation warning mark.

4.2 Care should be taken even after a CTU has been declared as ventilated. Gas can be held in packages of cargo, then desorbed over a long period of time, even over many days, raising the level of gas inside the cargo transport unit to above the safe exposure level. Bagged cereals and cartons with large air spaces are likely to produce this effect. Alternatively, gas and the fumigant sachets or tablets can become 'trapped' at the far end of a CTU by tightly packed cargo.

4.3 In reality any CTU that has carried dangerous or fumigated goods should not be considered as safe until it has been properly cleaned and all cargo residues, gaseous and solid, have been removed. The consignee for such goods should have the facilities to carry out this cleaning process safely.

4.4 When the fumigated CTU has been ventilated and unpacked, the fumigation warning mark should be removed.


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