Air handling unit treatment with Ozone: inlet air sanitization and deodorization

Air handling unit treatment with Ozone: inlet air sanitization and deodorization

Air handling unit (AHU) treatment with Ozone: inlet air sanitization and deodorization

Air conditioning systems on yachts over 24 meters include, in addition to fan coils, equipment called air handling units (AHUs). The AHU is an air conditioning system that takes outside air, treats it and finally sends it to the various cabins on board via ducting.
The air handling unit is essentially composed of an air filter, a heat exchange battery (both for cooling and for heating the air) and a fan.

What are the conventional solutions for the treatment of inlet air of the AHU (air handling unit)?

The AHU element whose task is to treat the air in terms of reducing odors and pollutants (bacteria, viruses, molds, fungal spores, etc.) is the air filter. Actually, it would be more appropriate to speak of a “filters set” as there are different types of filters and each air filter has its own function and a specific degree of filtration of dust, odors and pollutants. Therefore, there is no filter that works for everything!

Some types of air filters for air handling units are listed below.



  • Cell filters: they are used for the filtration of coarse dust. For this reason, the cell filter is almost always the first filter of the set and is also called “pre-filter”. Due to their structure, they are unable to stop the smallest particles, nor bacteria and odors.
  • Pocket filters: characterized by a glass microfiber filtering surface, they are used to filter the smallest particles. Also in this case, even if able to stop smaller sized powders, they are unable to sanitize the air.
  • HEPA filters: very high efficiency air filters and filtration capacity between 85% and 99.99%. Their cost is very high and for this reason they are used almost exclusively in environments where a high degree of air health is required (e.g. hospitals and healthcare environments).
  • Activated carbon filters: used for the abatement of volatile organic, inorganic and odorous substances. They require maintenance and regular replacement. Waste activated carbon must be disposed of appropriately by authorized companies according to the regulations.

What is the solution offered by Protea for the treatment of inlet air of the AHU (air handling unit)?

Following an initial filtration of the air (particulate matter), thanks to PROTEA ozonating systems (PROUTA line), it is possible to benefit from a real sanitization and deodorization of inlet air.
The Ozone produced by PROUTA system is placed on the AHU delivery, thus treating the air by means of an oxidative process. In other words, Ozone effectively eliminates odor molecules, bacteria, fungal spores and other pollutants present in the air.
Finally, PROUTA ozonizer is able to sanitize the internal ducts of the air handling unit thus avoiding the formation of bacterial outbreaks.

What are the advantages of Protea ozonating systems compared to conventional solutions?

During the design and construction of new ozonators, Protea’s goal is always to create a definitive solution characterized by minimal maintenance and the absence of spare parts and/or refills. Here are the main benefits of using Protea PROUTA line of ozonizers compared to air filters:

  • No recharges. Ozone is produced by PROUTA system only by means of electricity (low consumption). There is therefore no need to purchase refills and consumables as the treatment will be carried out automatically by generating Ozone thanks to the air present in the environment.
  • Free installation. PROUTA systems can be positioned up to 10 meters away from the Ozone injection point so as to allow them to be fixed according to the spaces available on board. Not only new boats, therefore, but also already sailing yachts, charter yachts and motor yachts in refit. In some cases, it is possible to take advantage of a single PROUTA system to treat multiple AHUs, with consequent economic savings and technical simplifications for the Shipyard or for the Customer.
  • No particular maintenance. New PROUTA ozonizers, thanks to the latest upgrades, do not need maintenance but only some simple periodic checks as a good rule for every electrical aid. The economic savings are therefore considerable considering the onerous cost of maintenance and filter replacement operations as well as cleaning and sanitizing the ducts (an activity that requires the removal of wooden panels on board as well as the use of specific cleaning systems).
  • Air sanitation. If we exclude HEPA filters which, as we have already said, are very expensive and not always installable, common AHU air filters are not able to sanitize and deodorize air in a profound way. The Ozone produced by PROUTA ozonators by Protea, on the other hand, sanitize inlet air by reducing most of the pollutants such as bacteria, viruses, odors, molds, fungal spores, etc.
  • Effective smell removal. The action of Ozone against odor molecules is extremely powerful and immediate. The effectiveness of the activated carbon filter, on the other hand, is quickly and considerably reduced if the required maintenance and regular replacement of the carbon is not carried out.
  • Sanitation of AHU ducts. The use of PROUTA systems, unlike the air filter, ensures the sanitization of the internal surfaces of the AHU ducts. This action avoids the formation of bacterial or fungal colonies along the delivery ducts of the air handling units.
  • Better air quality. The sanitization of the air taken from the outside using PROUTA ozonators allows you to benefit from a healthier environment on board. No more smells of food from other boats moored nearby. No more introduction of pollutants into the cabins due to the presence of bacteria and molds in the ducts. The effects of unhealthy air indoors are many: we invite you to also read the article about the so-called Sick Building Syndrome.


PROUTA ozonator line: sanitized air on board and AHU ducts always in healthy conditions

Like the DINAMICO3 line of ion-ozonating systems for the treatment of fan coils, PROUTA line of ozonators has the aim of guaranteeing deeply sanitized and deodorized air on board the yacht automatically and without maintenance or spare parts. PROUTA system is suitably sized by Protea based on the AHU air flow rate and can therefore be applied to motor yachts (generally AHUs are mounted on boats over 24 meters) up to mega yachts and giga yachts. In this period, even more than in the past, it is essential to ensure perfectly healthy air on board: Protea is convinced that its PROUTA ozonating systems represent the best solution for this specific on-board application.

For more information on Protea ozonizers or Protea’s Ozone solutions for the Marine Industry or other applications, do not hesitate to contact our offices at 0584/361274 or by email at


Sick Building Syndrome


Sanitization and smell removal in the bilge with Ozone