The exponential surge of international trade in recent decades has significantly increased cargo import and export globally. Today, more than 800 million TEUs (twenty-foot equivalent units) are moved annually across the globe.
Although shipping containers are essential to global trade, they have a few drawbacks. The enclosed environment of a container often results in limited ventilation, which can sometimes be an ideal breeding ground for pests and pathogens. A common way to eliminate pests and pathogens is through container fumigation.
In this article, we will take a closer look at how containers are fumigated and also discuss the two main methods carriers use to eliminate pests and pathogens in shipping containers. Lastly, we’ll touch on the importance of fumigation and the main types of cargo that require it.
What is Container Fumigation?
Container fumigation is the process of eliminating pests and pathogens from shipping containers through the use of chemicals or high-temperature treatment. This prevents the spreading of insects, rodents, pests, and infectious agents.
Shipping containers that have been extensively used, have holes, and lack proper maintenance can be breeding grounds for unwanted pests and harmful microorganisms contaminating cargo, and therefore need to be fumigated.
Containers are fumigated using fumigants, which are specialized chemicals that eradicate harmful microorganisms and protect cargo from contamination.
It’s important to note that not all shipping containers require fumigation. Containers that go through fumigation typically contain wooden products or packaging, grains, and textiles, as they can be ideal breeding grounds for insects and fungi.
Fumigating these containers prevents the introduction of harmful pests and pathogens into the ecosystems of the destination country, which helps to safeguard their agricultural, public health, safety, and environmental interests.
Types of Container Fumigation
There are various types of container fumigation used in the shipping industry. While fumigation methods vary, chemical applications and high-temperature treatments are the two most popular options.
Chemical fumigation involves using chemicals such as methyl bromide (MeBr) and phosphine (PH3). These fumigants are effective at eradicating insects, rodents, microbes, and other pests.
Both these chemicals are gases released directly into the shipping container. They eliminate pests and pathogens by targeting their respiratory systems, disrupting their metabolic process, and damaging their cells.
Chemical fumigation is highly effective in ensuring that the cargo inside the shipping container is pest and pathogen-free during transit and upon arrival. However, these processes need to be carried out by professionals and require supervision in most cases.
Chemical fumigants can also leave residue, affecting cargo, harming the environment, and posing health risks. This is why most shipping containers that undergo fumigation are covered with “tents” to minimize leakage and exposure.
High-temperature fumigation involves raising the temperature inside a shipping container to about 50 or 60 degrees Celsius for at least 20 to 30 minutes, depending on the location and conditions.
This temperature range is highly effective for dealing with insects, microbes, and larvae. Most of these pests are not able to survive in moderately high temperatures. High-temperature fumigation is a smart alternative to chemical fumigation, as it doesn’t leave behind any residue, which minimizes environmental impact and health concerns.
Fumigation through high temperatures requires specialized equipment for heating the container and monitoring the results. As some perishable cargo and other temperature-sensitive shipments spoil with temperature fluctuations, this method is not always used and only has specific applications.
Why Is Fumigation Necessary?
As mentioned earlier, fumigation eliminates pests and pathogens from shipping containers. Insects, rodents, and microorganisms pose a risk to the environment, local ecosystems, and public health.
Moreover, pests and rodents can also cause significant physical damage to cargo, reducing their value and in more extreme cases, rendering them worthless. In addition, pathogens and microorganisms can contaminate surfaces and pose health risks to cargo handlers.
Pest and pathogen contamination also have serious health, economic, and environmental consequences. When exposed to local environments, they can damage local biodiversity, agriculture, and ecological cycles, leading to economic losses and long-term environmental degradation.
What Type of Cargo Requires Fumigation
Not all shipping containers need to be fumigated. Containers are typically fumigated when originating from certain regions or when they carry specific types of packaging material or products.
- Wood – Wood is a common packaging material and comes in the form of pallets, crates, and boxes. While economical and convenient, they form ideal breeding grounds for pests and pathogens. Wood-harboring pests can hide in plain sight, easily damage cargo, and even infiltrate the local ecosystem.
- Grains – Rice, seeds, barley, quinoa, corn, and other grains are common food sources for rodents and insects. Shipments carrying pest-infested grains can easily damage other food sources and crops.
- Fruits & Vegetables – Fruits and vegetables are perishables that are highly vulnerable to pest infestation, especially in uncontrolled environments. Fumigation can remove them and prevent spoilage and contamination.
- Textiles – Many insects feed on natural fibers and fabrics, including clothes, shoes, and other types of apparel. Fumigation is often necessary to prevent physical damage to products.
- Assembled Furniture – Wooden furniture often has nooks, crevices, and cracks where insects and pests can hide. Fumigation can ensure these hiding places are uninhabitable for these pests.
What Are Container Fumigation Fees?
Fumigators (the company providing fumigation services) charge a container fumigation fee to the cargo owner, who is typically the importer or exporter. When an import agent or a freight forwarder is assigned to ship the container on behalf of the cargo owner, they may subcontract the fumigation process to their own vendor and outlay these costs.
While container fumigation costs are based on the type of fumigation, country, and service provider, they are typically between $100 to $400 for a 20-foot container and $300 – $600 for a 40-foot container.
Container Fumigation Exemptions
It’s important to note that not all types of wooden packaging materials, pallets, and cargo need to be fumigated. Understanding exemptions can help shippers and consignees save unnecessary fees and accelerate shipping lead times.
Each country will have its own list of fumigation requirements and it’s important to understand them before importing or exporting cargo. Below are some of the key fumigation exemptions:
- Presswood Pallets – These pallets are typically made from recycled wood, sawdust, and other unconventional wood sources. These nestable transport structures undergo high-temperature treatment. Hence, they’re typically free of pests and pathogens.
- Plastic Pallets – Plastic typically doesn’t attract pests because they’re non-porous and resistant to moisture, odor, and fungi. Additionally, they are highly durable and less susceptible to damage by rodents and larger pests.
- Wood Packaging – Certain packaging material that is made of processed wood or similar-natured wooden material and range from 1 mm to 6 mm are impervious to pest movement due to ISPM-certified phytosanitary measures (International Standards for Phytosanitary Measures).
- Pallet Blocks – These blocks are usually made from compressed wood waste, such as sawdust and wood shavings. Therefore, they are often pre-fumigated and are able to repel common pests.
- Wooden Barrels – Made from oak or cork, wooden barrels are designed to prevent biosecurity incursions due to fumigation and additives. Hence, they’re usually safe for shipping without the need for fumigation.
- Saw Dust – Chemical-treated sawdust is poisonous to insects and other pests. Therefore, they’re often exempted from container fumigation.
- Gift Crates – These are similar to wood packaging in the sense that it is made of treated wood components. As such, they are typically pest-free and do not require fumigation.
- Slipsheets – Commonly used to enhance cargo safety by acting as an intermediate layer between pallets and cargo, slipsheets are typically made from plastic or corrugated fiberboard. Most carriers use pest-repellent ones to avoid fumigation at ports.
Container Fumigation Procedure
Shipping containers that are fumigated go through a thorough and supervised procedure, which we’ll further elaborate on in the section below.
1. Sealing And/Or Tenting
The first step that fumigators do to initiate the fumigation process is thoroughly inspecting containers. They seal all openings, including the doors, vents, and gaps, to prevent fumigant leakage.
They then cover the container with a gas-tight tent or tarp to contain the fumigant and create an enclosed environment. This process is often referred to as “tenting” a container.
2. Introduction of Fumigant
The fumigator chooses the appropriate fumigant, depending on the type of cargo, pests, and level of contamination (typically methyl bromide and phosphine). Once selected, they carefully apply it into the container through liquid injection, pellet dispersion, or gas release. The fumigant should be distributed evenly within the container for the best results.
3. Exposure and Diffusion Period
Once the fumigant is applied, they close the tent or cover to let it work in a sealed environment. It will slowly permeate the cargo and container materials to reach and exterminate pests and pathogens in any infested areas.
The exposure time varies according to the type of fumigant used, pest species, and temperature conditions. This process typically lasts between a few hours to a few days for chemical fumigation and less than an hour for high-temperature fumigation.
Co-Founder & Writer
About the Author
Gerrit is a certified international supply chain management professional with 15 years of industry experience, having worked for one of the largest global freight forwarders.
As the co-founder of freightcourse, he’s committed to his passion for serving as a source of education and information on various supply chain topics.