Handling crop protection products has long remained one of the least mechanised parts of the spraying process. But as closed transfer systems begin to move from concept to commercial reality, attention is turning to what they can deliver on farm – and what should happen next. CPM explores.
“I reckon there’s probably a 25-30% decrease in our fill time.” IAIN ROBERTSON
By Charlotte Cunningham
For all the precision built into modern spraying, one part of the process has remained remarkably resistant to change. Machines have become smarter, guidance more accurate, and application technology increasingly refined. But for decades, the act of getting product into the sprayer has remained stubbornly manual – a process still reliant on lifting, pouring, rinsing and handling concentrated chemistry at close quarters.
However, that’s beginning to change. Closed transfer systems (CTS) have spent years being talked about as the next logical step for crop protection handling, offering a cleaner and safer alternative to conventional filling. But where once the concept felt distant – technically possible, but not yet truly embedded – the conversation has shifted. The technology is here, commercial systems are available, and packaging is beginning to move with it.
The question now is less whether closed transfer works, and more how quickly the industry can make it normal.
Of course, it’s not a new idea. As explored previously in CPM, CTS has been in development for decades, driven initially by concerns around operator exposure, environmental contamination and inefficiencies in the filling process. Research has long pointed to filling as one of the highest-risk stages for point source pollution, while the physical handling of multiple small packs has remained one of the few areas of farm practice yet to be fully mechanised.
But while the rationale has been clear for some time, meaningful adoption has taken longer. And that’s largely because the system had to work in practice, not just in theory, says sprayer operator Iain Robertson. “We wanted to come up with something that was going to be practical and purposeful,” he explains. “It had to be safer, quicker and easier than what we were already doing.”
That principle became central to the early development work. Iain was part of a group of operators brought together more than a decade ago to assess potential CTS solutions, feeding directly into the development of systems and the ISO standards that now underpin them. The aim wasn’t simply to build something new, but to ensure it would actually be used.
The risk of getting that wrong was clear. Iain points to examples elsewhere where closed transfer had effectively become a compliance exercise – installed to meet requirements, but too slow or cumbersome to use in reality. “We didn’t want a situation where it just sat there under a tarpaulin,” he says.
Among the major breakthroughs was achieving agreement across crop protection manufacturers on a common cap format. It sounds like a small detail, but in practice it unlocked one of the biggest barriers to progress. With standardised pack openings and a universal interface, different CTS units could work across products and brands. “That was the crux of the whole closed transfer deal,” he says.
From there, the focus shifted firmly onto usability and early systems quickly highlighted the importance of speed. One gravity-fed design trialled during development took several minutes to empty a 10-litre container – far too slow to be viable in a working spraying operation, notes Iain.
By contrast, modern systems operate under vacuum, drawing product directly from the container and eliminating multiple handling steps. According to Iain, the impact on efficiency has been significant. “I reckon there’s probably a 25-30% decrease in our fill time,” he says. “Not just because it’s drawing it out under vacuum, but because you don’t have to open lids and pour and rinse.”
Just as importantly, the system changes how operators work during filling. Rather than handling one task at a time, multiple processes can run simultaneously – one container being loaded through the CTS, another being rinsed, and another draining. Over the course of a day, that compounds into meaningful time savings.
It’s a point echoed by Harry Fordham of Syngenta, who says efficiency has become one of the strongest arguments for adoption. “Primarily, people think about it as a safety concept, to reduce exposure to operators and the environment,” he explains. “But actually, the more work we’ve done on this, it increases the efficiency of the operation and the speed of it.”
Based on work carried out with operators, including Iain, Harry says tank fill speed can improve by around an average of 20-30%, depending on tank size and the number of products involved. In practical terms, that can equate to more hectares covered in a day, particularly where spraying windows are tight and workloads are increasing.
While that efficiency gain is compelling, it sits alongside the original driver for CTS – reducing exposure.
For Iain, one of the most striking demonstrations came during a trial comparing conventional filling with closed transfer using UV dye to simulate contamination. He filled a sprayer via the induction hopper, then repeated the process using CTS. Under UV light, the difference was immediately visible. “It was mind-blowing,” he says.
The analysis went further, with PPE removed and tested to quantify contamination levels. The results showed a dramatic reduction in exposure when using closed transfer – something backed up by wider industry work. Harry points to CropLife Europe trials indicating operator exposure risk can be reduced by as much as 95%.
Yet both are keen to stress that this isn’t about criticising current practice. “There’s nothing wrong with the way we’re doing it at the moment,” says Iain. “It’s very good and it’s very safe; we’re just showing there’s more we can do.”
His analogy is a simple one – conventional filling is like wearing a seatbelt; closed transfer adds the airbags. That nuance is important, not least because one of the biggest barriers to adoption remains the perception that change isn’t yet essential.
From Syngenta’s perspective, significant progress has been made. Across Europe, the company has rolled out new packaging and cap combinations across relevant liquid products, redesigning both packs and production lines to accommodate closed transfer. That level of investment has been substantial, requiring changes not only to packaging, but also to manufacturing infrastructure and logistics.
But the wider supply chain is still catching up. Easyconnect currently involves multiple manufacturers, and while some are well advanced in rolling out compatible packaging, others are at earlier stages. For growers, that creates a practical dilemma. If only a proportion of products arriving on farm are CTS-enabled, the return on investment can feel limited.
“When they’re getting products into their spray store, probably only 10, 20 or 30% of products have the caps,” says Harry. “So I understand fully why they question, ‘Why would I invest now?’”
There’s a similar lag on the machinery side. While sprayer manufacturers are increasingly integrating CTS couplers into new machines, this is still a relatively recent development. For businesses replacing sprayers on a five- or six-year cycle, adoption may simply align with that replacement timeline.
And yet, there’s a strong case for acting sooner, argues Harry. For one, financial support has helped drive early uptake – in England, as well as through water company initiatives, subsidies have significantly reduced the cost of installing CTS equipment. In some cases, that support covers a substantial proportion of the investment, lowering the barrier to entry.
At the same time, there are signals that wider regulatory alignment may follow. The Netherlands, for example, is introducing mandatory closed transfer capability on sprayers, reflecting a broader European shift towards reducing operator and environmental risk at the point of filling. “My perspective is that one way or another, this is coming as a regulatory requirement,” believes Harry. “I can’t tell you when, but I would say to buy it now while it’s cheap.”
That potential regulatory trajectory links closely to another benefit of CTS – its role in supporting product availability. As scrutiny around operator safety and environmental impact continues to increase, technologies that demonstrably reduce exposure could help secure the future of certain active ingredients.
“From a crop protection manufacturer’s perspective, it can allow us to keep products on the market long-term or register products that otherwise may not have been approved,” he explains.
At a time when the industry remains under pressure from a shrinking chemistry toolbox, that could prove a critical advantage.
Despite the progress, however, CTS is still evolving. One of the key challenges remains accurate measurement of small volumes. While transferring full containers is straightforward, dosing smaller quantities requires additional systems with different manufacturers taking varying approaches. Some rely on flow meters, others on weighing systems, while alternative designs incorporate integrated measuring cylinders.
Each have strengths and limitations, particularly when operating in the harsh environment around a sprayer, where dust, moisture and corrosive products can all impact performance.
For Iain, this is where development is still very much ongoing. He also highlights improvements in packaging design, including clearer graduations and more visible containers, as well as refinements to rinsing systems and safety features that prevent accidental misuse. “There’s been lots of little changes and they all add up,” he says.
At the same time, the way CTS is integrated into sprayers is beginning to change. As more operators adopt the technology, manufacturers are having to rethink how these systems are mounted, protected and incorporated into machine design. In some cases, this has led to more compact or foldable units that better fit the realities of field operation.
Beyond that lies the next stage of development – digital integration. Both Iain and Harry point to the potential for CTS to link directly with farm management systems, allowing spray recommendations to be transferred to the sprayer and product automatically metered out according to the planned application. While still in development, such systems could reduce operator workload, improve accuracy and streamline record keeping.
Although not yet standard practice, this highlights how CTS is becoming part of a wider shift towards more automated and connected spraying systems. For now, though, the appeal remains grounded in the practical.
After decades of modernising almost every other aspect of spraying, the industry is finally addressing one of its most persistent weak points. Closed transfer systems may have taken time to move from concept to commercial reality, but the direction of travel is now clear.
The remaining challenge is less about the technology itself, and more about alignment across the supply chain – from manufacturers and machinery builders through to growers and operators.
If that alignment comes, the biggest change may not be how CTS works, but how quickly it becomes routine. And when it does, the idea of pouring chemicals by hand may start to feel like a practice that belonged to a different era…
This article was taken from the latest issue of CPM. Read the article in full here.
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