Fumigation

Fumigation applies chemical treatments to control pests in cargo, particularly grain and timber, while managing environmental and health risks. This may include, among others, controlled fumigation of cargo such as grain or timber, use of approved fumigants (for example, phosphine), monitoring of gas concentrations, ventilation procedures before handling, safe storage and handling of fumigation chemicals, and alternative pest control methods where feasible.

For DMC ports, safe fumigation management can prevent introduction of pests and diseases, protect biosecurity and agricultural systems, minimize chemical exposure risks, reduce uncontrolled release of toxic substances, and support safe trade operations (DAFF, 2023; NEA, 2024).

Fumigation is an important biosecurity tool, particularly for bulk grain exports and imports, where cargo may carry insect pests that could become invasive in destination markets. Phosphine is the most widely used fumigant for grain and other dry commodities, applied either in bulk to cargo holds, silos, or fumigation chambers. Methyl bromide use has been progressively phased out under the Montreal Protocol due to ozone depleting potential, with quarantine and pre-shipment (QPS) applications excluded from the phase-out and critical use exemptions agreed by the Parties for specific other uses.

Safe fumigation management includes, among others, qualified fumigators licensed under national regulations, approved application methodologies and dosages, gas concentration monitoring during fumigation and ventilation, ventilation procedures before cargo discharge to reduce worker exposure, personal protective equipment for fumigation workers, and secure storage of fumigation chemicals (NEA, 2024).

Fumigation chamber designs, can support controlled fumigation with vapor recovery or scrubbing to prevent atmospheric release of fumigants. Regulated venting and recovery can reduce environmental exposure and worker health risks. For bulk grain fumigation in ship holds or silos, gas tight integrity and controlled ventilation are essential to prevent fugitive emissions.

Alternative pest management approaches may be applied where feasible, including, among others, heat treatment (for packaging materials under International Standards for Phytosanitary Measures No. 15, ISPM 15), controlled atmosphere storage (low oxygen), refrigeration, and integrated pest management combining multiple methods. Biosecurity authorities typically require specific treatments for specific pest risks, limiting flexibility to alternatives.

In DMC contexts, grain fumigation is particularly relevant for imports from Australia, South America, and other major grain exporters. Rice and other domestic commodities may also require fumigation for export. Coordination with national biosecurity authorities, such as Malaysia's Department of Agriculture, the Indonesian Quarantine Authority (Badan Karantina Indonesia), and Viet Nam's Plant Protection Department, supports compliance with importing country requirements and domestic biosecurity objectives.