Photo above: Fire in potato storage facility. The new generation of sprout inhibitors cannot be used with the outdated equipment. Unfortunately, this has already caused many fires. pic2021@DamianRuitenga.
Photo above: Research into the properties of the new sprout inhibitors was an important part of the development of the Nebulizer Agro. Fire safety as a first requirement. pic2021@studiolab
Photo above: The Nebulizer Agro at the HINT, during the test and droplet measurement in the WUR Agrolaboratory in Wageningen. picservatech@2022wur.lab.
Photo above: Double rainbow. We like to maintain control by building in double guarantees. Fire safety through construction and temperature monitoring and fire tests. pics@nature-james-wheeler.

About Sluys Techniek and Servatech BV

Dingeman van der Sluys, who has been active in technology for over 35 years, specializes in finding solutions to technical issues with his company Sluys Techniek. In particular with installations and machines. His international customers ask him for a diagnosis, technical advice or, on site, to repair a machine or control unit. He uses his experience and, if possible, the most modern electronics to repair complex machines. Together with his ability to improvise, he comes up with solutions for technical failures worldwide.

Accumulated experience gives confidence. Do what is promised. A deal is a deal. Usually it works. And sometimes it doesn't work. But always with attention to sustainability and safety.

The development of the Nebulizer Agro is the result of technical problems due to the approval of other sprout inhibitors for potatoes. The European Food Safety Authority, EFSA, wanted to withdraw the authorization of the widely used sprout inhibitor Chlorpropham, or CIPC, in mid-2019. A ban on use was announced, but it would take until April 2021 before this actually happened.

Several manufacturers have been approved for substitutes and 1.4 Sight® and Argos® are the most important of these to date. These very expensive resources have such specific product properties that their use is not justified with existing equipment. During the period when the resources were changed, Sluys Techniek carried out several tests with different equipment, during which irresponsibly high risks were identified. As an example, we cite tests with the equipment in combination with a new agent, which produced a flame of up to 12 meters in length. It was the end of this test. Later we did the test again outside the workshop with the necessary precautions. That outdoor test was also very dangerous despite the better conditions. Another flash of flame and again at least 12 meters. The temperatures were too high for these agents. In other cases, the pressure in the storage facility was too high, causing many valuable resources to escape. The odor clouds released were clearly noticeable outside the shed…. It was a clear decision for Sluys Techniek. These new resources cannot be used with the existing equipment without adjustments. In modern and well-insulated potato sheds it is certainly not inconceivable that the pressure will rise so high when applied that an explosion occurs, causing incalculable damage. A spark in a switch box is enough.

There were and are reports in the press reporting large fires in storehouses, also in Germany, Belgium and France. One only has to Google 'fire potato shed' or 'fire potato shed' for shocking results. As a result of these problems, the authorization of Argos® and 1.4 Sight® has been withdrawn to investigate the risks during treatment. The results have not been published, but the Product Labels, the Safety Information Sheets, the SDS and the instructions for use have been adapted to the risks. The result of this is that neither the producer nor the contractor accepts any liability for damage during treatment. The risks of working with the new resources are great. The authorization was obtained due to their effective effect, but the way in which these products can be used safely has not been sufficiently clarified. The existing equipment could not be used safely without risk

Then Sluys Techniek decided to do things differently, as the son of an arable farmer, he had learned the tricks of preserving potatoes from his father. Believing there must be another option, he began to consult with the farmers in the area. He examined the building construction and electrical installation of various sheds and the available ventilation capacity. In order to use the new resources, a clear picture of the current repositories had to be obtained. Certain technical details, such as the location of the control cabinets, are important to possibly provide with overpressure in order to exclude the risk of fire. In this way the design of the new machine began. He rents out his own Tolsma barn to a farmer in the area, so he is also busy with the storage of potatoes every season. It is an art in itself, after the harvest in September, the potatoes are wheeled into the shed and the work begins. The most optimal temperature, the right humidity. To achieve this with the fluctuating outside temperature, the interplay of internal or external ventilation is a true art.

The potato consists of 80% water, and is therefore very sensitive to being kept at rest for a long time, sometimes up to 8 months. That is the reason for using so-called sprout inhibitors, which must be applied very accurately. The price of the new resources is so high that the degree of efficiency must be maximum. The better the storage, the better the potato. Small deviations in color and taste have major consequences. Therefore, the demands on the equipment are high, safety, accuracy and reliability are necessary. The potato, in all its manifestations, is third on the list of the most eaten foods in the world, after grain and rice. Important enough to take its preservation seriously. The ban on the use of CIPC applies throughout Europe. All Member States are aware of this problem. The market for an innovative machine is large.

For example, Sluys Techniek started drawing and constructing in January 2020 and used its contacts with arable farmers in the area. What is the experience like and how can it be improved? First build each new element, test it, and take it apart again. What weight is still acceptable, how small can it be made, and is it not too big to transport? The noise level had to be pleasant, the power consumption as low as possible, the heating sufficient but not too high. Do not use additional air, only the agent with the correct pressure to prevent losses. The various components such as pipes and seals were also tested separately for properties in combination with the products. The different flash points, temperature, volatility, there should be no combustion because soot formation means loss of agent. For example, a hose had shrunk after 3 days in no less than 30%, or a special rubber compound had completely dissolved in the agent. Another became much too long due to another means. Every day, in the evening, sometimes through the night because something has to be finished for the test the next day. Building electronics is also a specialty in itself, the properties of the product, the controls, the control and emergency facilities are indispensable for the proper functioning of the machine. The importance of build quality, the materials used, the ease of operation, even after many years of use. A prototype was used during the 2020 - 2021 season, but it did not work sufficiently in practice and was dismantled again. Many tests were carried out to achieve the correct pressure and temperatures. So the development continued, trying again and again. Until the result was a prototype for working with the resources. 

In the meantime, the storage season 21/22 had started and the potato sheds were filled. The real work had to begin. We decided to collaborate with neighboring farmers and immediately put the developments into practice. 6 different storage locations in the area were selected for the practical tests. We made 2 cm small openings in different places, because it is important to keep the Nozzle IN to the right place of the airflow. Only then do we make maximum use of the energy of the ventilation system. The carried agent evaporates in the air stream and thus reaches every place in the shed evenly. The arable farmers witnessed how the Nebulizer Agro worked in their own barn, and were surprised by the compact size and the pleasant sound. Due to the combination of the correct amount of agent, the nozzle used, the applied pressure and temperature, the yield is easily adjustable. The maximum capacity of 30 liters per hour proved to be more than sufficient in practice. Despite adjustments, the first storage season went well and the barns were empty again. The arable farmers were satisfied with the first use of the Nebulizer Agro. The practical tests have continued in the 2022/2023 season. Continuing developments in efficiency result in savings in the use of resources. The Start and Stop technology, The CanBase, the system to change the nozzle and so on. The safety and reliability will continue to prove themselves. The 2023/2024 season has started and the practical tests have started. This season is similar to previous seasons, but the Nebulizer Agro has undergone multi-year development. The operation has been tested in all kinds of temperatures, at minus 6ºC, at 30ºC in the sun, also in storms and rain or kilometers through rough terrain. The countless starts and stops, all kinds of variations in desired pressure and temperatures. Many times changing Nozzle. Switch from Argos® to 1.4 Sight® and then again and vice versa. Operation at a height of 5/6 meters. Efficiency implemented down to the last detail with proven savings on valuable resources. For us and the participating arable farmers, the usefulness of practical tests is clear. 


The CE quality mark was awarded at the beginning of 2022, in accordance with the provisions of the Machinery Directive with the classification NEN/EN/ISO/IE. See p. SPECS.

A measurement was also made at WUR Wageningen, AgroLab Plant Research, led by Dr. HJ Holterman. This concerns a measurement of the droplet spectrum where 2 different laser beams are used to measure the droplets. See page SPECS.