The verification process begins with a review of the engineering calculations and system design. Next, the team inspects the installation and checks whether all installed components comply with the design documentation.

The team then commissions the system and checks the functionality of all components. After that, airflow rates are balanced and the achieved airflow is measured. Finally, key indoor air quality parameters are verified.

To explain this process more clearly, the following sections describe the installed system, its design constraints, and the specific engineering challenges.

In an approximately 200 m² apartment in Belgrade, Marquis Intelligence designed and implemented a central ventilation system with a high-efficiency heat recovery unit.

To meet the client’s demanding requirements, Marquis Intelligence added a dedicated filtration chamber, a bipolar ionization system, and a steam humidifier.

Architecture as a Limiting Factor in Ventilation System Design

This project shows how strongly building architecture can influence the selection, configuration, and long-term performance of a ventilation system.

Building Location and Apartment Position

The apartment is located in an existing multi-storey building with a glass façade. The building has an Energy Performance Class A rating.

From the earliest design stages, Marquis Intelligence had to adapt the ventilation system to the existing architecture, available installation space, and other building services.

A Glass Façade as a Constraint on Ventilation System Selection

At the beginning of the project, Marquis Intelligence evaluated both centralized and decentralized ventilation concepts.

The glass façade ruled out individual façade penetrations for the outdoor air intake and exhaust required by decentralized ventilation units. For that reason, the team rejected decentralized ventilation as technically infeasible.

Marquis Intelligence therefore selected a central ventilation system with a radial duct distribution network serving each room independently.

Even then, the façade could not accommodate either the outdoor air intake or the exhaust air discharge. The team therefore designed separate intake and exhaust routes.

Fresh outdoor air enters from the roof terrace. The team had to consider the location of other rooftop installations, especially existing kitchen and sanitary exhaust systems connected to the building’s vertical shafts.

The design also had to account for the shaft carrying fresh air from the roof to the apartment several floors below.

These constraints made both the engineering design and the subsequent performance verification particularly demanding.

SEE ALSO: Decentralized Home Ventilation Systems: Advantages and Limitations

Interior Design as a Design and Installation Constraint

The apartment’s interior design significantly influenced how the central ventilation system could be installed.

The first major decision concerned the location of the heat recovery unit. The team then determined the position of the humidifier, the outdoor air intake, the exhaust air discharge, and the duct routes.

Suspended ceilings were available only above the entrance areas of the rooms. This constraint led to the use of supply grilles utilizing the Coandă effect.

The ductwork had to fit within the available ceiling voids without compromising the interior design or requiring unnecessarily invasive construction work. Construction works themselves were outside the contractual scope of Marquis Intelligence.

Protecting the existing interior during installation was equally important. This included the elevator and common corridors, as well as the apartment’s flooring, furniture, and other interior finishes.

Ventilation Design Calculations

Marquis Intelligence designed the ventilation system in accordance with DIN 1946-6. The calculations covered minimum ventilation for moisture protection, reduced ventilation, nominal ventilation, and intensive ventilation.

The manufacturer’s design software calculated a nominal airflow of 184 m³/h and an intensive airflow of 239 m³/h. However, calculations alone cannot replace professional judgment about the specific characteristics of each project.

For that reason, the final design used a ventilation unit with a higher capacity than the calculated minimum requirement.

The team determined airflow rates according to the intended use of each room and balanced them across the apartment. Fresh air enters the bedrooms and dining area. Extract air leaves through the kitchen, bathrooms, and other spaces with higher moisture and odor loads.

The team also coordinated the ventilation system with the apartment’s air-conditioning system.

Airflow balancing takes place centrally through balancing valves on the supply and extract manifolds. This is one of the key advantages of the installed system.

Heat Recovery

The central ventilation unit uses a high-efficiency counterflow plate heat exchanger.

Supply and exhaust air pass through separate channels and do not mix. Heat transfers through the heat exchanger surfaces from one air stream to the other.

SEE ALSO: Plate or Rotary Heat Recovery Units in Residental Central  Ventilation?

The ventilation system provides the required quantity and quality of fresh air, while indoor temperature is maintained by the heating and cooling systems.

Air Treatment

Marquis Intelligence installed a dedicated filtration chamber upstream of the central ventilation unit. It contains a HEPA H14 filter and a molecular filter.

The HEPA H14 filter captures extremely fine airborne particles. The molecular filter reduces certain gaseous pollutants and unpleasant odors.

High-efficiency filtration also increases airflow resistance and pressure drop. For that reason, the team had to verify the available fan static pressure and assess the filtration chamber’s effect on the overall airflow.

A bipolar ionization system provides an additional stage of air treatment. It operates on the principle of dielectric barrier discharge (DBD). The ionization unit is installed in the supply air plenum immediately upstream of the distribution manifold. From there, the system distributes ionized air throughout the apartment.

The system also includes a steam humidifier, in accordance with the client’s requirements and needs.

During commissioning, the team found that the water downstream of the building’s central water treatment system had insufficient electrical conductivity for stable humidifier operation.

The humidifier water supply was therefore reconnected directly to the municipal water main. Measurements confirmed that the water conductivity met the manufacturer’s requirements for reliable operation.

This detail shows why a central ventilation system cannot be designed in isolation from other building services.

Existing Local Exhaust Systems and the Central Ventilation System

The kitchen range hood operates independently of the central ventilation system.

It operates intermittently and at airflow rates significantly higher than those required for continuous apartment ventilation. The existing bathroom exhaust fans also remained in operation. At the same time, the central ventilation system has its own dedicated extract points.

This arrangement separates three functions: continuous ventilation of the apartment, intermittent boosted exhaust from the bathrooms, and separate extraction of cooking vapors and kitchen emissions.

Internal and External System Verification

The design and installation passed through several levels of professional review.

A Mechanical Engineer prepared the ventilation calculations. A licensed consulting engineer then reviewed the engineering design and technical documentation.

The project parameters were also submitted to the equipment manufacturer. The manufacturer processed them using its centralized engineering software in Germany.

This review covered total and individual airflow rates, supply and extract air distribution, ventilation unit selection, and compatibility with the manufacturer’s technical requirements.

After installation, Marquis Intelligence submitted photographic documentation of the completed system to the manufacturer. The manufacturer then reviewed the equipment positioning, component interconnections, and key installation details.

The verification process therefore included engineering calculations, review by a licensed engineer, technical verification by the equipment manufacturer, and inspection of the completed installation.

Airflow Verification

Following system commissioning, the team measured airflow at the intake grille of the ventilation chamber. During the measurement, the heat recovery unit operated in Boost Mode.

The team used professional airflow measurement equipment. They divided the grille surface into six equal measuring zones and took measurements at three points within each zone.

After applying a 5% correction factor for possible external influences, the corrected airflow rate was 428 m³/h.

The measurement confirmed the airflow achieved at the intake side of the ventilation chamber in Boost Mode with clean filters.

Virtually Silent Operation

Supplying the required quantity of fresh air is not enough to ensure a high-quality ventilation system. Air distribution within the occupied spaces is equally important.

In this apartment, the system operates virtually silently. Occupants do not perceive noticeable airflow.

This result depends on proper duct sizing, appropriate air velocities, a sufficient number of supply terminals, correct terminal positioning, and precise system balancing.

Independent Indoor Air Quality Measurements

After approximately 24 hours of continuous system operation, with all windows kept closed, an independent scientific institute carried out instrumental measurements of the apartment’s indoor air quality.

Using professional monitoring equipment, the following indoor air quality parameters were recorded:

• CO₂: 668–889 ppm
• TVOC: 207–246 ppb
• Formaldehyde: 16 ppb
• Fewer than 50 particles/cm³ within the measured particle size range of 0.3–10 µm
• Ozone (O₃), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂): not detected

CO₂ concentrations remained within an appropriate range even in rooms occupied by considerably more people than assumed in the original design calculations. For example, a home office designed for one occupant was occupied by four people during part of the testing period, yet the measured CO₂ concentration reached only 889 ppm.

SEE ALSO: CO₂ in Your Home – Is It There and Where Does It Actually Come From?

No measurable concentration of ozone was detected during system operation.

A particle concentration of less than 50 particles/cm³ corresponds to very clean indoor air, according to the classification applied in the laboratory report. It should be noted that this result refers to the instrument’s measurement range of 0.3–10 µm.

The report further states that the combined effect of ventilation, filtration, and bipolar ionization would be expected to become even more pronounced under conditions of poorer outdoor air quality.

What Does This Project Demonstrate?

This project shows that a central ventilation system can also be retrofitted into an apartment in an existing multi-storey residential building. However, the building must provide suitable spatial and technical conditions.

Such a solution involves far more than installing a central ventilation unit.

The configuration and total cost of the system depend on the building itself and the client’s requirements. Other important factors include the required airflow, the level of air treatment, duct routing, the locations of the outdoor air intake and exhaust air discharge, installation conditions, and additional system components.

SEE ALSO: Residential Ventilation by Marquis Intelligence
SEE ALSO: FAQ – Home Ventilation

What Determines the Price of a Central Ventilation System?

The price of a heat recovery unit is not the same as the cost of a complete ventilation system.

A fully engineered solution includes much more than the equipment itself. It also includes engineering calculations, system design, ductwork, installation, airflow balancing, commissioning, and performance verification.

One of the most important aspects of this project is that the team did not evaluate the result solely on the basis of the installed equipment.

The verification covered the engineering design, system configuration, completed installation, achieved airflow, and key indoor air quality parameters.

Verifying the performance of a central ventilation system is the final and indispensable stage of project implementation. It confirms whether the completed system operates in accordance with the engineering design requirements.

Long-term reliable operation also depends on regular maintenance. The best continuity is achieved when the company that designed, installed, and commissioned the system continues to maintain it in accordance with the manufacturer’s recommendations and actual operating conditions.

This article is part of the Marquis Intelligence “Mini Case Studies” series.
Document ID: MI-MCS-09.3Q-26
Document Title: Mini Case Study: Verifying the Performance of a Central Ventilation System in an Apartment

The post Mini Case Study: Verifying the Performance of a Central Ventilation System in an Apartment appeared first on Marquis Intelligence.

With the opening of this resort, Montenegro welcomed its first Mövenpick hotel within the global Accor hospitality group. The resort is located in the Bay of Kotor, an area renowned for its exceptional natural beauty and cultural-historical significance. Mövenpick Teuta Kotor Bay features hotel rooms, luxury residences and penthouses, a diverse selection of restaurants, wellness facilities, a private beach, and outdoor relaxation areas.

In such an environment, air discharged from the hotel kitchen should remain completely unnoticed.

Food Preparation Odors as a Potential Reputation Risk in Hospitality

In the hospitality kitchen odors can become a negative reputational factor. Guests generally perceive unwanted food odors as part of an unpleasant overall experience.

This is especially important in properties that include terraces, residential units, open-air restaurants, wellness facilities, and premium apartments. Guests expect an atmosphere of freshness, tranquility, and comfort throughout the property.

At this point, a technical solution ceases to be merely equipment and becomes part of the invisible technology of luxury. At Mövenpick Teuta Kotor Bay, this requirement was recognized and addressed from the earliest stages of project development.

Air Quality as Part of the Guest Experience

Luxury hotels are typically defined by their architecture, interior design, views, gastronomy, and wellness amenities. These are the elements guests notice immediately.

However, a lasting impression is often shaped by what guests do not see. Unpleasant odors, ventilation noise, stuffiness, or air carrying traces of food preparation can undermine even the most carefully designed hospitality environment.

Guests do not think about kitchen hoods, exhaust ductwork, filtration systems, treatment chambers, or control systems. They simply experience the space. What they consciously notice is usually discomfort: noise, unpleasant odors, excessive heat or cold, or poor air quality.

When the air remains pleasant and outdoor, wellness, and dining areas are free from kitchen odors, the technology has fulfilled its purpose. In a resort such as Mövenpick Teuta Kotor Bay, which builds its identity around the combination of the sea, heritage, sustainability, and wellness, such details are never left to chance.

Good Air Quality Is Becoming a Growing Priority in Hospitality

This approach is not an isolated example within Marquis Intelligence projects. Similar solutions have been implemented in the Bay of Kotor region and its surroundings for Restaurant Dojmi in Kotor, Restaurant ONE in Tivat, and Mamula Island Hotel. In addition, a previous mini case study on Hilton Belgrade demonstrated how IAQ solutions in hospitality can be adapted to different zones within a hotel property.

SEE ALSO: Mini Case Study: Hotel Hilton Belgrade

In all of these examples, the principle remains the same: guests do not need to understand how the system works, but they should be able to feel the difference.

Why Kitchen Exhaust Air Purification Matters in the Hotel

Kitchen exhaust air is not simply air that needs to be removed from a space.

During food preparation, particularly in professional and hotel kitchens, a complex mixture is generated containing warm air, significant amounts of water vapor, grease particles, smoke, aerosols, and odors. If such air is simply extracted from the kitchen and discharged outdoors without adequate treatment, the problem is not solved. It is merely relocated.

SEE ALSO: FAQ – Kitchen Exhaust Air Extraction and Purification

In standard buildings, the consequences are often technical and safety-related: grease accumulation in the ductwork, reduced system efficiency, unpleasant odors in the surrounding area, and increased fire risk.

In a luxury hotel, the consequences can be even broader.

Kitchen odors in terraces, restaurant areas, wellness facilities, or residential apartments are unacceptable. They affect not only guest comfort but also the reputation of the hotel brand.

Environmental Responsibility and Premium Guest Experience

As part of a hospitality brand with a strong commitment to sustainable practices, Mövenpick Teuta Kotor Bay addressed the issue of kitchen odor control from the earliest stages of project planning. In this context, kitchen exhaust extraction and air purification are not optional additions but a natural component of modern sustainable hospitality standards.

PHOENIX Systems at Mövenpick Teuta Kotor Bay

For Mövenpick Teuta Kotor Bay, Marquis Intelligence supplied two PHOENIX kitchen exhaust air purification systems. Their role extends beyond simply removing air from the kitchen. Before being discharged into the outdoor environment, the exhaust air undergoes a controlled purification process.

PHOENIX systems are engineered to effectively remove grease, particulate matter, and unpleasant odors from kitchen exhaust air. In previous project presentations, Marquis Intelligence reported system performance figures of more than 99% removal of grease and particulates and more than 92% neutralization of unpleasant odors.

In practice, these results are important for more than technical reasons.

They enable intensive kitchen operations while minimizing the impact on surrounding spaces. In a luxury hotel environment, this means that operational activities remain in the background while the guest experience stays clean, calm, and unobtrusive.

Installation and Maintenance Are Essential for Safe and Efficient Operation

The treatment chambers were installed on a dedicated platform to ensure easy access for regular maintenance. In luxury hospitality, technical systems must be not only efficient but also reliable over the long term. For that reason, maintaining kitchen exhaust and air purification systems is not an additional responsibility but a prerequisite for safety, stability, and service life.

Good engineering is often recognized precisely in such details – in aspects guests never see but upon which the continuity of quality depends.

SEE ALSO: HVAC and IAQ System Maintenance – The Pillar of Reliability

This is where the distinction between equipment as a product and an engineering solution as part of a property’s long-term value becomes evident.

In luxury hospitality, technology must operate without drawing attention to itself. It must be powerful yet quiet. Efficient yet unobtrusive. Present yet invisible.

That is the essence of the invisible technology of luxury.

From Technical Risk to Premium Experience

In a previous technical article, Marquis Intelligence explained why commercial kitchen exhaust ventilation is about much more than simply removing air from a kitchen.

Without proper treatment, kitchen exhaust air can lead to grease accumulation, odor dispersion, reduced system efficiency, and increased fire risk. These problems are not theoretical. They often become apparent only after a system begins to lose performance or when consequences become visible within the building and its surroundings.

SEE ALSO: Commercial Kitchen Exhaust Ventilation: From Fire Risk to Safe Operation

In a high-end hotel, the same technical challenge acquires an additional dimension.

The objective is not merely to ensure safety and functionality. The goal is to ensure that technical processes take place without compromising the atmosphere of the property, the reputation of the brand, or guest expectations.

In other words, what may be a safety issue in one facility becomes an experience issue in a luxury resort.

Every Property Has a Different Context

Ventilation solutions for commercial and hotel kitchens cannot be approached as universal systems.

In some projects, the key challenge may be limited installation space or a protected façade. The challenges may also be a low discharge point, noise restrictions, or proximity to pedestrian areas. In another, such as a luxury resort, the challenge lies in preserving a premium experience across the hotel, restaurant, wellness, and residential areas.

In a previous mini case study focused on commercial kitchen ventilation in a city center environment, Marquis Intelligence demonstrated how spatial limitations, architectural protection requirements, discharge point locations, and user proximity require a comprehensive engineering approach.

SEE ALSO: Mini Case Study: Commercial Kitchen Ventilation in Constrained Conditions in the City Centre

At Mövenpick Teuta Kotor Bay, the context is different, but the principle remains the same.

The Solution Does Not Begin with Equipment

Kitchen exhaust air purification in hotels cannot be approached by starting with equipment selection alone. The solution begins with understanding the space.

When a single resort integrates hotel rooms, residences, apartments, restaurants, wellness facilities, beaches, terraces, and outdoor relaxation areas, kitchen exhaust extraction and purification must be considered part of the property’s overall operational and experiential design.

Sustainable Hotels and Responsibility Toward Air Quality

Sustainability in hospitality is often associated with energy efficiency, water conservation, waste reduction, and responsible resource management. However, sustainability also includes what a property releases into its surrounding environment.

Kitchen exhaust air does not disappear once it passes through a kitchen hood. If left untreated, it leaves the building carrying odors, grease particles, and airborne contaminants. In sensitive tourist destinations, urban environments, and historically significant areas, such an approach is no longer sufficient.

This is especially true for a resort whose identity relies on natural surroundings, open-air experiences, seaside living, and the reputation of an international hospitality brand. For this reason, kitchen exhaust air purification becomes part of a responsible relationship toward the environment in which the hotel operates.

It contributes to environmental protection, odor reduction, preservation of guest comfort, and the long-term operational stability of building systems.

When Engineering Is Invisible but Noticeable

If a system performs properly, guests will never know where the treatment chambers are located, how air moves through the ductwork, or how it is purified before discharge. Yet they will know that they feel comfortable. The terrace does not smell like a kitchen. The wellness area remains a place of relaxation. Restaurant spaces maintain freshness and comfort.

Mövenpick Hotel & Residences Teuta Kotor Bay presents how modern luxury increasingly depends on systems that remain behind the scenes. Architecture, views, design, wellness, and service create the first impression. Clean air, the absence of unpleasant odors, and a stable indoor environment determine how long that impression lasts.

Through the implementation of PHOENIX kitchen exhaust extraction and air purification systems, Marquis Intelligence contributed to creating the technical foundation for a premium hospitality experience in one of the Adriatic region’s most prestigious new resorts. The true technology of luxury often remains invisible.

Sources and Additional Context

• Forbes article on the Mövenpick Hotel & Residences Teuta Kotor Bay resort
• Blic: “Swiss Luxury on the Adriatic Coast: Montenegro’s First Mövenpick Hotel Opens”
• Official Mövenpick Teuta Kotor Bay / The Queen of the Bay project website
• Previous Marquis Intelligence LinkedIn posts related to the Mövenpick Teuta Kotor Bay project

This article is part of the Marquis Intelligence “Mini Case Studies” series.

Document ID: MI-MCS-08.2Q-26

Document title: Kitchen Exhaust Air Purification at Mövenpick Hotel Teuta Kotor Bay

The post Mini Case Study: Kitchen Exhaust Air Purification at Mövenpick Hotel Teuta Kotor Bay appeared first on Marquis Intelligence.

A commercial space on the ground floor became available for lease. An attractive location. A representative building. Ceiling height of approximately 5 meters – almost ideal for a hospitality venue.

The space was soon converted into a restaurant.

However, behind this seemingly simple idea, a critical technical issue emerged: commercial kitchen ventilation. In this building, already constrained by significant technical and spatial limitations, further complicated by its status as a protected cultural heritage property, ventilation proved particularly challenging.

Initial Client Requirements

From the very beginning, it was clear that standard solutions would not be applicable.

It was not possible to route exhaust air to the highest point of the building, which is the conventional approach in commercial kitchen ventilation design.

At the same time, uncontrolled discharge of air containing grease and odours was not an option. The building façade is protected by the state, and directly above the restaurant is the office space of a company specialising in air quality.

The kitchen itself presented additional constraints. It was located in a semi-basement, with windows at sidewalk level. Less than 1.5 meters above them were the windows of the ground-floor space.

The client’s initial request was clear: a unit for exhaust air extraction and purification – primarily to eliminate unpleasant odours.

According to the initial plan, the ventilation system was to be installed by a standard contractor.

Challenges Escalate

The problem quickly evolved beyond simple odour removal into controlled air management under real conditions.

Although initially engaged as an equipment supplier, the Marquis Intelligence team, consistent with its professional standards and responsibility toward the surrounding environment, became involved in analysing the entire system.

It soon became clear that the problem could not be addressed in isolation.

In addition to odour elimination, it was necessary to ensure proper air capture and direction above cooking appliances. This required a custom-designed kitchen hood, adapted to the spatial limitations.

Under these conditions, a wall-mounted inclined hood with rear connections was developed, instead of the standard top connection.

SEE ALSO: FAQ – Kitchen Exhaust Air Extraction and Purification

The originally selected contractor withdrew from the project due to these non-standard requirements. Marquis Intelligence then took over this part of the project as well.

Unexpected On-Site Challenges

During implementation, additional issues arose that were not directly related to ventilation but had a significant impact on the project.

During the preparation phase, concerns emerged regarding the feasibility of transporting equipment into the basement kitchen. Detailed measurements by the Marquis Intelligence team revealed that structural columns and thick load-bearing walls – over 50 cm thick – prevented the installation of large equipment. Additionally, the existing opening between the kitchen and the restaurant area was insufficient in size.

At that point, the installation of restaurant equipment had already begun, and the placement of a display counter directly in front of the opening was planned.

A decision was made to adapt the project to actual on-site conditions. The installation of the display counter was cancelled. The existing opening was enlarged before tiling works began. This intervention enabled not only the installation of the ventilation system but also the smooth installation of the complete kitchen equipment – avoiding serious issues in later project stages.

Technical Solutions

Taking into account all identified challenges, the system was designed as an integrated whole.

Special attention was given to ventilation ducts, where welded joints were applied to ensure high airtightness and fire safety.

Additional issues addressed included:

• controlled air discharge
• outlet positioning near a pedestrian zone
• noise reduction through silencers

The air outlet was carefully positioned to ensure controlled airflow velocity and direction.

Acoustics

Particular attention was also paid to the system’s acoustic performance.

Even though the air extraction and purification unit is located within the kitchen itself and even integrates an additional working surface, its operation is almost silent.

At the external weather louvre, there is no noticeable airflow or odour, confirming both system efficiency and control of discharge parameters.

Air Discharge Grille

An additional challenge arose in defining the discharge grille.

Since its lower part is positioned at sidewalk level, it was necessary to consider the possibility of snow accumulation during winter.

The lower section of the grille was therefore closed, preventing the ingress of precipitation and ensuring reliable operation in all weather conditions.

Maximizing Space Utilization

One of the key requirements was fitting the entire system into a limited space.

The air extraction and purification unit was positioned at floor level, while its upper surface was used as an additional work area.

This solution enabled full functional integration of the system into the workspace, without loss of usable area.

Daylight

Positioning the unit at floor level and integrating a work surface also improved the use of available space, allowing better penetration of natural daylight into the kitchen.

Final Solution

The originally selected contractor completely withdrew from executing the standard scope of work. As a result, the complete commercial kitchen ventilation system was ultimately realised by Marquis Intelligence. The exhaust ventilation system for this kitchen was adapted to all specific technical and spatial constraints of the project.

The implemented system included:

• a kitchen hood designed according to real operating conditions
  This enabled more efficient capture of steam, grease, and odours generated during kitchen operation.
• a multi-stage exhaust air treatment system
  This significantly reduced unpleasant odours and air pollution before discharge into the outdoor environment.
• a sound attenuator
  This ensured quieter system operation and reduced impact on the surrounding area.
• controlled exhaust air discharge
  This provided a more stable and safer direction of exhaust airflow.
• a carefully positioned discharge outlet in a pedestrian zone
  This minimised the system’s impact on the everyday use of the surrounding space.
• welded high-sealing ventilation ducts
  This increased system safety and ensured more reliable long-term operation.

Results

The results are immediately visible in the daily operation of the facility:

• elimination of unpleasant odours
• stable and reliable system performance
• controlled discharge with no impact on the surroundings
• low noise levels
• safe operation in proximity to occupants

More Than Ventilation

This project demonstrates that commercial kitchen ventilation does not depend on a single system component, but on a holistic engineering approach.

SEE ALSO: Mini Case Study: Kitchen Exhaust Air Purification at Mövenpick Hotel Teuta Kotor Bay

In projects of this type, technical solutions do not begin with equipment, but with understanding real spatial constraints and user requirements. Continuous on-site presence and involvement in the broader project context transformed the role of the supplier into that of an engineering partner.

Marquis Intelligence has previously written about the technical aspects and risks of commercial kitchen exhaust systems.

SEE ALSO: Commercial Kitchen Exhaust Ventilation – From Fire Risk to Safe Operation

Recommendations as Proof of Client Satisfaction

The success of this system did not remain only at a technical level. Shortly after commissioning, new inquiries began to arrive – directly as a result of recommendations from this restaurant.

However, perhaps the most important aspect of this project is its verifiability.

This project requires no presentation.

It is enough to experience it – and to hear the recommendation.

This text is part of the “Mini Case Studies” series by Marquis Intelligence.
Document ID: MI-MCS-07.2Q-26
Title: Mini Case Study: Commercial Kitchen Ventilation Under Constrained Conditions in the City Centre

The post Mini Case Study: Commercial Kitchen Ventilation Under Constrained Conditions in the City Centre appeared first on Marquis Intelligence.

In December 2025, the technical team at Marquis Intelligence faced one of its most demanding air quality projects to date: a café where smoking is permitted. Tobacco smoke that stings the eyes and nose. An unpleasant odor. Limited fresh air intake and real technical constraints of the facility required a complex solution – one that goes beyond standard ventilation approaches. In other words, improving air quality in a smoking-allowed café was anything but an easy task.

The project was defined through two implementation phases. The first was carried out in December 2025. The second in January 2026. In both phases, measurable and verified results were achieved.

This mini case study demonstrates how Marquis Intelligence, through a holistic engineering approach, achieved stable, long-term, sustainable air quality under real-world conditions in a café where smoking is permitted.

The Root of the Problem – Smoking and Tobacco Smoke

Tobacco smoke is a complex mixture of fine particles and gaseous pollutants. It contains suspended particles of extremely small size (PM2.5 and smaller), volatile organic compounds (VOC), carbon monoxide, and numerous other toxic components.

In enclosed spaces with limited fresh air supply, these substances remain trapped and accumulate. This creates pollution conditions that negatively affect health, comfort, and people’s ability to work. A particular challenge lies in the fact that tobacco smoke does not behave like an odor that can simply be “extracted” through ventilation. Tobacco smoke is a mixture of a large number of chemical compounds, some of which are highly harmful and toxic, as well as finely dispersed particles. An additional issue is the reduction of oxygen concentration and the increase of carbon dioxide concentration.

That is why such a space requires a targeted, multi-layer technical solution.

Legal Regulations Still Allow Smoking in Hospitality Venues

In hospitality spaces where smoking is allowed, the issue is not only the presence of smoke, but its retention within the space. The consequences include irritation of the eyes and respiratory tract, unpleasant odors, and reduced comfort for both guests and employees.

In this case, the café is located on the ground floor of a modern business building in New Belgrade. The amount of available outdoor air was limited. Increasing fresh-air intake through the building façade was not feasible. Standard ventilation did not deliver satisfactory results. During peak periods, tobacco smoke in the café caused stinging in the eyes and nose.

The project goal was clearly defined: real improvement of air quality—not merely formal compliance with technical requirements.

Regulatory Framework and Space Organization

In the Republic of Serbia, the legal framework related to smoking in indoor spaces is defined by the Law on the Protection of the Population from Exposure to Tobacco Smoke (“Official Gazette of the Republic of Serbia”, No. 30/2010). The law prescribes conditions and restrictions for smoking in public spaces, including hospitality venues.

In accordance with regulations, the organization of smoking and non-smoking zones plays a significant role in reducing exposure to tobacco smoke, especially for non-smokers. Therefore, the spatial position of the non-smoking zone in relation to the main entrance is important. It must be located right next to it, so that non-smokers are not forced to pass through the smoking zone where air pollution is more intense.

In this facility, the existing spatial organization did not follow this logic. An additional entrance was used more frequently. For that reason, it was designated the main entrance, and a non-smoking zone was established adjacent to it. However, this entrance represents an internal connection to the business building and, as such, should not have been treated as the main entrance.

Therefore, as part of the holistic technical solution, the positions of the smoking and non-smoking zones were modified in accordance with regulations and actual user movement patterns within the space.

Marquis Intelligence’s Holistic Approach

The existing technical solution was not satisfactory.

Marquis Intelligence applied its holistic approach, based on the 4D work matrix.

The application of the 4D matrix in this project included analyses of pollution sources (tobacco smoke), spatial airflows, system technical limitations, and real user habits.

The proposed and adopted solution included combining multiple technologies to improve air quality. Precise airflow analysis and careful positioning of intake and supply elements of the system were also implemented.

Special attention was paid to ensuring that air from the smoking zone does not re-enter the non-smoking area.

Phase One of the Project – Improving Air Quality in the Café

The Marquis Intelligence team ensured that the installation of air-quality improvement equipment would not compromise the venue’s interior design.

Within this project, a solution was implemented for the first time in Europe featuring an advanced system for continuous monitoring and control of air quality, adapted to the real operating conditions of a hospitality facility – Smart IAQ, from a U.S. equipment manufacturer.

In addition, air treatment using dielectric barrier discharge was implemented, provided by the German manufacturer Bioclimatic GmbH, with whom Marquis Intelligence has maintained a two-decade-long partnership.

See also: Partner par excellence – who and why

Phase Two of the Project – Improving Air Quality in the Café

Air quality in the café was already significantly improved in the first phase. Particles and a large amount of volatile organic compounds were eliminated. However, a lack of fresh air remained noticeable, as expected. For this reason, a second phase of the project was planned from the outset, with the goal of improving air quality in the smoking-allowed café while respecting the facility’s technical limitations.

As part of the second phase of implementation, the design, production, delivery, and installation of a portion of the ventilation system were carried out to supply an additional amount of fresh air treated by bipolar ionization.

See also: Bipolar air ionization – the first page of Google

Results in Practice

The effects were noticeable immediately after system commissioning. Unpleasant odors were eliminated. The subjective feeling of stuffiness disappeared. Air quality in the smoking-allowed café was visibly improved.

An employee who arrived first in the morning noticed that, unlike the previous musty smell, the air now felt “fresh, as if freshly washed laundry had been brought in.” The facility management confirmed that the smoke and odor issues no longer occur.

If the Goat Lies, the Horn Does Not

All visitors and employees come and go, but something remains constantly present in the interior—and suffered before the project was implemented. These are the potted plants.

The dominant plants in this space are bird-of-paradise plants (Strelitzia). Before the project was implemented, their growth had stagnated. For a long time, they produced no new leaves. And you cannot fool them.

People will come and leave. Some will catch the peak of a smoke-filled space, others will come when the entrance doors are wide open. They will have different impressions. However, plants that remain in the space at all times cannot lie.

A few weeks after the first phase went live, an indicative secondary effect of improved air quality was observed. The potted plants began developing new, large, healthy leaves. This effect appeared without any changes in plant maintenance.

As the saying goes: “If the goat lies, the horn does not.”

Maintenance and Long-Term Reliability

From the very beginning of the project, system maintenance was discussed. In settings such as this, long-term efficiency depends equally on the quality of the solution and the installed equipment, as well as on planned maintenance during operation.

Experience once again confirmed that general manufacturer recommendations are not sufficient for specific facilities. Full effects can only be achieved through engineering-customized solutions and continuous technical responsibility.

During equipment importation, Marquis Intelligence secured the necessary replacement molecular filters and maintains them in stock, along with all other potentially required spare parts.

See also: HVAC and IAQ System Maintenance – The Pillar of Reliability

Real-Time Measurements

Alongside the sophisticated equipment installed in this demanding air-quality environment, measurement and control systems were integrated to monitor air quality.

SmartIAQ is an intelligent air-purification system compliant with ASHRAE Standard 241-2023. It reduces total volatile organic compounds (TVOC), formaldehyde, PM1.0, PM2.5, PM4.0, PM10, and NOx. The system includes digital control and self-regulation via solid-state air-quality sensors that manage the flow rate of purified air.

Air purification via dielectric barrier discharge, applied in both project phases, also includes sensor control, and sensor measurements of volatile compounds are displayed on the controller.

All devices can be connected to the building’s BMS (Building Management System) upon user request.

Conclusion

This mini case study shows that air quality in a café where smoking is permitted can be improved, but it requires far more than standard ventilation or standalone devices.

Combining technologies, proper space organization, understanding airflow dynamics, and a methodological approach based on the 4D work matrix represents the key to success.

Client trust and clear, direct feedback from daily use of the space confirm the validity of Marquis Intelligence’s approach.

This text is part of the “Mini Case Studies” series by Marquis Intelligence.
Document ID: MI-MCS-06.1Q-26
Document title: Mini Case Study: Air Quality in a Café Where Smoking Is Allowed

The post Mini Case Study: Air Quality in a Café Where Smoking Is Allowed appeared first on Marquis Intelligence.

If you didn’t know, the first attempt to sterilize air in an operating theatre was recorded in 1867, when Sir Joseph Lister at Glasgow Royal Infirmary sprayed carbolic acid (phenol) to eliminate microbes from the air. That marked the first effort to sterilize air in medical history.

At that time, surgeons performed operations wearing tailcoats. There were no dressings or gauze, and surgical instruments were not sterilized. Operating theatres resembled auditoriums with wooden floors and spectators watching the procedures.

Over time, progress arrived. Air filtration systems based on the mechanical separation of microorganisms and particles were developed.

The first cleanroom standard was introduced in the United States in 1961, followed by the first European standard in 1983 – not that long ago.

Modern Approach to Clean Air in Hospital

Today, modern technical and technological advancements provide incomparably more efficient solutions. The goal remains the same – to ensure clean air in hospital environments. This purified air is now very close to sterile, though absolute sterility is not achieved.

A prime example of a cutting-edge medical facility is the Ferona Specialised Gynaecology Hospital in Novi Sad. This hospital specializes in gynecology, obstetrics, and in vitro fertilisation (IVF). Air quality has been recognized as a key success factor in IVF and in ensuring patient, newborn, and staff safety.

In line with standards, this hospital features hygienic air-handling units, HEPA filters, and all other equipment prescribed by regulation.

However, for those who care deeply about hygiene and the health of patients and employees, that wasn’t enough.

Why Clean Air in Hospital IVF Departments Is Especially Important

In IVF procedures, clean air plays a decisive role. Any air contaminant – whether micro-particles, microbes, or chemical pollutants, including odours – can affect the process outcomes. Numerous modern studies confirm this.

SEE ALSO: How Air Pollution Affects In Vitro Fertilisation

Maintaining air quality under such conditions is part of the daily routine. And clean air means far more than comfort.

Interestingly, the very beginnings of general hospital hygiene emerged from gynecology departments.

SEE ALSO: Ignaz Semmelweis – The Saviour of Mothers and Newborns

The Best Seek More Than Standards

During the first heating season, residential buildings in the Novi Sad district, where Ferona is located, used various solid and liquid fuels. Unfortunately, burning waste materials was also common. All of this caused unpleasant odours to penetrate the hospital premises.

For that reason, Ferona Hospital reached out to Marquis Intelligence to request a solution that would ensure impeccably clean air in hospital spaces. Marquis Intelligence already had extensive experience in hospital air treatment, with notable applications at the Institute for National Health in Podgorica, the Institute for Cardiovascular Diseases in Sremska Kamenica, and the Clinical Centre of Vojvodina in Novi Sad.

The project was agreed upon, with guaranteed efficiency in removing volatile organic compounds and odours clearly defined in the contract. In other words, this spotless hospital would no longer be affected by smoke odours from nearby households.

The best always follows standards – but also goes beyond them.

A Solution That Makes a Difference

Following its established 4D matrix methodology, Marquis Intelligence proposed an unconventional air-purification solution for the air-supply duct of the hygienic air-handling unit. The installed and proven system was based on the principle of bipolar ionisation. In this case, analysis showed that bipolar ionisation achieved through dielectric barrier discharge (DBD) would yield the best results – and it did.

SEE ALSO: Air Bipolar Ionisation – Similarities Between DBD and NP Technologies

The result is clean air in the hospital – minimal maintenance, maximum effects

The system for additional air purification was carefully designed and implemented by Marquis Intelligence. It provided effective odour neutralisation and improved both air and surface hygiene throughout the hospital. The installed equipment requires minimal maintenance while delivering maximum efficiency.

After commissioning, the air quality in Ferona Hospital improved significantly. Unpleasant odours were eliminated. The goal was achieved – impeccably clean air in hospital facilities that exceeds health safety and comfort standards.

Ferona Hospital – A Leader in Reproductive Medicine

For Ferona, clean air is not merely a technical requirement, but part of its medical ethics – an obligation to every patient and every new life beginning here.

It is no wonder that a hospital with such high standards, surpassing typical hygiene requirements, has been recognized nationally as a leader in reproductive medicine.

Ferona – a symbol of trust, life, and excellence.

The Ferona Specialised Gynaecology Hospital in Novi Sad ranked first in IVF for 2024/2025, according to HealthCare Quality Watch – Best Private Hospitals in the Republic of Serbia.

After months of independent voting by Serbian doctors, combined with patient satisfaction analysis and other objective factors, Ferona received this prestigious award from the Centre for Health Quality Promotion.

This year, Ferona celebrates ten years of dedicated service. Over that period, more than a thousand babies have been born there – and the Marquis Intelligence team is proud to have contributed to that success.

What Ferona Hospital in Novi Sad Says

“We are incredibly proud that our efforts and work have been recognised as highly professional and of outstanding quality. Behind us are ten years of service, thousands of babies born, and a dedicated team of doctors, nurses, and management who have given their knowledge, passion, and time. We will continue to work and improve, to make this world a better and brighter place for every new life and the smiles that give us hope back.

Thank you for your trust – we will do our best to honour it and become even better.”
– Ferona Hospital Statement

Conclusion

Microbiological monitoring of air and surfaces has been satisfactory and has remained so, which is the foundation of every IVF/medical facility. The key challenge was an olfactometric issue, which was resolved after implementing our solution.

This article is part of the “Mini Case Study” series by Marquis Intelligence.
Document ID: MI-MCS-05.4Q-25
Document Title: Mini Case Study: Impeccably Clean Air in a Hospital in Novi Sad

The post Mini Case Study: Impeccably Clean Air in Hospital in Novi Sad appeared first on Marquis Intelligence.

That’s why Marquis Intelligence has combined technical expertise with online authenticity to build its digital authority in air quality across the region.

“For Marquis Intelligence to remain successful and sustainable in the fields of ventilation and air quality, our digital framework must be equally strong,” says Vladimir Janaćković, CEO.

This mini-case study presents data from Google Analytics (GA) and Google Search Console (GSC), providing clear evidence of teamwork and consistency behind the significant progress of this small company.

The results reveal a powerful rise in visibility and engagement.
Behind every number are articles written with care, passion, and a genuine wish to provide accurate and helpful information.
It was demanding, but it paid off. Take a look at the numbers that follow.

How Marquis Intelligence Became a Digital Authority in Air Quality

It all began on the company’s 30th anniversary, when, under the guidance of Dragan Varagić, Marquis Intelligence stepped boldly into the digital world.
It was a journey into the unknown. A vast new space that continually expands and offers new opportunities every day.

A well-crafted strategy, combined with dedicated work and technical expertise, enabled the company to gain visibility quickly. First regionally, then internationally.

It started with a single landing page in Serbian. Soon after, an English version followed. The next milestone was launching a bilingual blog, developed simultaneously in both languages.

SEE ALSO: New brand and website for 30th birthday of Marquis Commerce

What Preceded the Visit from Google Bots

Before any significant shift in metrics, a thorough SEO optimisation process was conducted – first on the Serbian version of the site, with the English version still undergoing refinement.

In September 2025, six new bilingual blog posts were published. This move significantly increased the frequency and diversity of content, contributing to stronger signals of relevance and authority.

These strategic activities likely triggered what appears to be a Google reevaluation, a process that often precedes improved search visibility.

A Likely Google Re-evaluation?

On October 10, 2025, Marquis Intelligence’s website experienced a noticeable spike in activity.

According to Google Analytics, the site recorded over 1,500 visits in a single day, including 23 concurrent sessions from Santa Clara and Clifton, both recognised hubs of Google infrastructure.

This type of behavior strongly suggests a thorough technical inspection, most likely a Google content reevaluation. While this cannot be confirmed with absolute certainty, all available indicators suggest that conclusion.

Learn more about this intriguing development in one of the previously published articles titled Google Re-evaluation of the Marquis Intelligence Website?

Performance Growth

During the past three weeks, Marquis Intelligence recorded remarkable progress across key website metrics.

• Search clicks: +200% increase.
• Average Google Search position: now consistently on the first page.
• Click-Through Rate (CTR): +78% rise, nearly twice as many users clicked on search results compared to the previous period.
• Mobile “good URLs”: from 0 to 49.
• Active users: +40.9% year-over-year.
• Impressions: +39.5% year-over-year.

As a result, the Marquis Intelligence website now appears regularly on the first page of Google Search results. Several articles are ranked in the top one to two positions for keywords related to ventilation and air quality.

This growth confirms the website’s transition into the “Established Presence” category, a milestone achieved by fewer than 3% of websites at this stage.

Within the context of Serbia’s digital market and the technical B2B niche, such progress is sporadic, yet it stands as clear evidence of authenticity, consistency, and high-quality content.

Global Reach and Engagement

Analytics from October 10 confirm visits from four continents.
Europe. Australia. North America. South America. All within 24 hours.

User engagement time further supports the high quality and relevance of the content:

• Serbia: average of 10+ minutes per session.
• Brazil: over 5 minutes.
• Europe and North America (Germany, UK, Austria, Denmark, Belgium…): several minutes of active engagement.

Such metrics are rare in technical niches and represent a strong confirmation that Marquis Intelligence is successfully emerging as a digital authority in air quality.

“We weave niche stories about air into compelling, data-driven content. Always from a fresh perspective. That’s the difference between the average and the exceptional,” notes Vladimir Janaćković, CEO.

For more on the blog content strategy, read our post: Blog as a Digital Trace of Air

Turning Reevaluation into Recognition

Over 100% growth in indexed pages within 20 days (domain reevaluation and entry into the Increased Crawl Rate phase).

What initially appeared to be a technical anomaly turned out to be a milestone of progress and algorithmic trust.

Google has acknowledged the authenticity, consistency, and structural integrity of the content. Marquis Intelligence successfully transformed this presumed reevaluation into a breakthrough moment, further solidifying its role as a digital authority in air quality.

This process once again confirms that digital excellence is inextricably linked to technical proficiency. They enhance one another.

Note

Although this article focuses on the behind-the-scenes activities of Marquis Intelligence, it forms an integral part of the company’s operations. It is part of the series titled “Mini Case Studies”.

Document ID: MI-MCS-04.4Q-25
Document Title: Mini Case Study: Establishing Digital Authority in Air Quality

The post Mini Case Study: Establishing Digital Authority in Air Quality appeared first on Marquis Intelligence.

>> See also: Residential Ventilation by Marquis Intelligence

Project Challenge

The apartment had approximately 100 square meters and was located in a new building in New Belgrade. It was already occupied and in daily use. That meant the apartment ventilation system had to be a retrofit installation.
The challenges were clear:

• Limited space for installation.
• The client did not want major construction work.
• The solution had to be fast, efficient, and discreet.

Marquis Intelligence Apartment Ventilation Solution

The Marquis Intelligence team completed specialized training in Germany. This guarantees reliability and high-quality execution.
Ventilation system calculations were performed online, on the server of our German partner, in line with international standards.
After several days of planning and organizing the work, the central apartment ventilation system with heat recovery (HRV – Heat Recovery Ventilation) was fully implemented in just three days.

>> See also: Heat Recovery Ventilation – 8 Key Benefits for Your Home

Installation Details

Marquis Intelligence placed the devices inside a custom-built niche in the closet, while the technical team ensured that the system blended seamlessly with the interior design.
They extended the air distribution system through the hallway and living room, thus creating a unified central ventilation zone for the entire apartment.
To achieve optimal airflow and balanced air distribution, Marquis Intelligence utilized special diffusers designed to harness the Coandă effect.

Measurement Results

After Marquis Intelligence completed the installation and started the system, they performed control measurements. The results were precise:
With the apartment ventilation system on, the concentration of PM particles smaller than 0.3 µm was 20 times lower compared to natural ventilation (opening windows).

Why does this matter?

Because particles often carry oxides, heavy metals, and even microbes. By eliminating PM2.5 particles, especially the ultrafine ones, the indoor air quality improves significantly.

>> See also: The importance of indoor air quality in our homes

Additional Measurements

Marquis Intelligence also measured CO, formaldehyde, and ozone. The levels of these pollutants were not detectable.
All measurements taken by the team were conducted at stable humidity and temperature levels, which are essential for comfort and health.

Client Feedback

Marquis Intelligence has installed many apartment centralised ventilation systems and house ventilation systems. Clients keep coming back.
One client from Krunska Street in Belgrade shared his experience after failing to install a ventilation system in his new seaside home:

“I thought the air by the sea was good. But then my friends visited me. The next morning, after their visit, when I entered the living room and felt the stuffy air, I realized this never happens in my Belgrade apartment. So, I realized that I should have installed ventilation with ionization here as well.”

This feedback clearly shows the difference between natural ventilation and controlled ventilation.

Conclusion

This case study demonstrates that Marquis Intelligence’s controlled centralized apartment ventilation system, featuring heat recovery, HEPA filtration, and integrated ionization, delivers significantly healthier and more reliable results than simply opening windows.
With precise design and advanced technology, even mid-sized apartments can achieve solutions that protect health, extend lifespan, and conserve energy.

For more information, please do not hesitate to contact us.

This article is part of the Marquis Intelligence “Mini Case Studies” archive.
Document ID: MI-MCS-03.3Q-25.
Name of the document: Mini Case Study: Apartment Ventilation in Belgrade

The post Mini Case Study: Apartment Ventilation in Belgrade appeared first on Marquis Intelligence.

What truly defines a premium workout experience? A high-end gym setup? Advanced fitness equipment? Exclusive design certainly plays a role, much like branded sportswear. But what about a factor we rarely see, yet always feel – air quality in the gym?

Earlier this year, Marquis Intelligence was invited to assess air quality in a luxury private home gym located in one of Belgrade’s finest residential villas. The private gym we are discussing surpasses the standards of many high-level professional fitness centers, both in terms of surface area and equipment quality.

Even though the gym was equipped with a ventilation system, the user reported discomfort during exercise, including a sensation of heaviness in the air. Measurements were made to find the cause that Marquis Intelligence’s team of experts expected to be causing the problem. The results confirmed the suspicions.

The Challenge

Even with the existence of the ventilation system, the air quality in the gym was unsatisfactory.

• Body heat, smells, microbes, and moisture that accumulate quickly in the atmosphere.
• Aerosols and particles are released into the air during intense exercise, including skin and hair particles.
• Volatile Organic Compounds (VOCs) released into the air from rubber flooring, leather surfaces, textiles, and cleaning agents.

This is not an isolated case. Almost every gym faces similar, and often more serious, air quality challenges in the gym environment. Problems are usually more pronounced in gyms with more users, smaller space per user, lower height of the space and poorer ventilation.

Our real-time measurements confirmed that the air quality in the gym was not satisfactory.

• Extremely high total volatile organic compounds (TVOC) levels exceeding 3,000 ppb were determined (classified as severely polluted).
• Elevated particle counts, including ultra-fine particles (<0.3 µm), were high.
• A noticeable sensory load, consistent with user complaints.

The Solution

To address these challenges, while carefully considering the limitations and specifications of the existing ventilation system, the Marquis technical team selected and implemented a custom bipolar ionization system. It was designed with careful consideration of the limitations and specifications of the existing ventilation system, using the Marquis Intelligence 4D Process Matrix.

An air purification system based on bipolar ionization of air on the pressure of recuperator units was designed and installed. This system simultaneously reduces the concentration of pollutants from the air that are released inside the gym itself.

At the same time, ions provide immediate neutralization of charged particles, odors, and bioaerosols. Ionization reduces the concentration of pollutants in occupied zones and helps maintain a cleaner, healthier environment throughout the workout. At the same time, it provides easier breathing.

The configuration featured a single regulation loop, calibrated specifically for this environment, ensuring optimal ion distribution in the active training zone.

Within minutes of operation, users began to notice a difference. One of the employers remarked:

“You may not come here often, but I walk through this place every night. And yes – it’s much easier to breathe now.”

That is the reason why our clients always come back to us asking for more.

>> SEE ALSO: Mini Case Study: Hotel Hilton Belgrade

The Results

Independent before-and-after measurements confirmed the effectiveness:

• TVOC levels dropped by more than 60% within the first 40 minutes,
• The downward trend continued in the following hours, confirming the lasting effectiveness of the solution.
• Formaldehyde was reduced by nearly 7%, even though initial levels were already low,
• No increase in ozone levels (remained ≤ 0.01 ppm).
• Ion concentration doubled, reaching over 1,000 ions/cm³ in the breathing zone.

These are not just technical improvements; they represent tangible benefits for health, well-being, and performance.

Ionization in Sports: A Long-Standing Secret

The positive effects of negative air ions on athletic performance have been studied for decades. As early as the 1960s, Soviet scientists applied ionization during the training of elite athletes – gymnasts, boxers, swimmers, and track & field competitors.

Studies reported improvements in:

• endurance of up to 900%,
• enhanced coordination by 300%, and
• faster reaction times by 100% compared to control groups

(source: “Secret Russian Sports Weapon Disclosed”, Special Olympic Report, 1960s).

More recently, controlled studies in elite sports settings have shown that ionized environments contribute to improvements.

• Improved oxygen uptake kinetics during intense physical activity. (Source: Nimmerichter et al., 2013).
• Accelerated post-exercise recovery, especially following high-intensity workouts. (Source: Ryushi et al., 1998).
• Reduced respiratory load and PM exposure during indoor training. (Source: Zhang et al., 2022).

Canadian documentation further confirms the practical application of bipolar ionizations in Olympic and professional sports facilities. (Sources: “Ionizing Air Cleaner Makes Sports Inroads”, “Sports Facilities Provide Sizzle for a Company Selling Air”).

With no known side effects and measurable gains in comfort, breathing ease, and physiological recovery, ionized air is increasingly viewed as a vital environmental factor in both elite and everyday fitness settings.

Key Takeaways

The most crucial key takeaway is the best user experience

• Even high-quality air ventilation systems may need additional air purification.
• Air quality in the gym environments has a direct impact on how we feel during physical exertion as well as what the results of that exercise will be.
• Bipolar air ionization quietly and efficiently improves the quality of treated air.
• The improvement is both measurable and noticeable, in minutes.

True well-being begins with what we often take for granted: the air we breathe.

Looking to enhance the air quality in the gym or wellness space? Maybe home?

>> SEE ALSO: 8 Benefits of Heat Recovery Ventilation (HRV) for Your Home
>> SEE ALSO: The Importance of Indoor Air Quality in our Homes

This mini case study clearly shows how modern air purification technology can improve the experience of staying not only in homes, offices and hotels, but also in spaces like gyms, spas and exercise rooms.

Discover how Marquis Intelligence can help you breathe better, train harder, and recover faster – safely and effectively.

This article is part of the Marquis Intelligence “Mini Case Studies” archive.
Document ID: MI-MCS-02.2Q-25.

The post Mini case study: Air Quality in the Gym appeared first on Marquis Intelligence.

Increasingly, people, including hotel guests worldwide, are becoming aware of the invisible factors that shape genuine comfort, particularly indoor air quality. During the planning and design of Hotel Hilton Belgrade, the project team recognised the importance of clean indoor air from the very beginning. As a result, they invited Marquis Intelligence to support them throughout the project.

Today, indoor air quality has become a key differentiator in luxury hospitality, particularly in urban environments where outdoor air is often polluted. As a result, guests are becoming more susceptible to allergies and airborne irritants.

Over the past seven years, starting with the hotel’s opening in downtown Belgrade, Marquis Intelligence has implemented seven carefully customised indoor air quality (IAQ) solutions. Each solution was designed for a specific area, from public guest spaces to staff-only facilities.

The expertise Marquis Intelligence has developed through advanced air purification technologies has earned international recognition and prestigious awards. One of them is the first prize in the “Best in Tech” category at The Brit List Awards in the United Kingdom.

>>See also: Brit List Award for Best Technical Solution

Integrated Air Treatment from Day One

From the earliest design stages, the Hilton Belgrade team entrusted Marquis Intelligence with designing and implementing centralised air treatment for the hotel’s common areas.

Marquis Intelligence installed advanced air purification systems on four HVAC units serving several hotel zones:

• Two Kings restaurant.
• SkyLounge rooftop bar.
• Tsar Dušan ballroom.
• Meeting rooms.
• Event halls.

To begin with, these systems operate continuously to deliver clean and healthy air throughout the hotel’s main zones. Moreover, they function so quietly and discreetly that guests rarely notice them. Yet, their role remains essential in maintaining a safe and comfortable indoor environment. Even, often unnoticed, air is crucial for customer experience.

Guest Rooms and Staff Canteen

As the collaboration between Marquis Intelligence and the hotel grew, new requirements naturally emerged.
The team introduced a five-station localized air purification system for the guest rooms. This flexible setup actively removes particles, allergens, microbes, and odours, creating a clean and comfortable indoor environment.

On May 1, 2025, Marquis Intelligence completed the latest installation as part of the first phase of indoor air quality improvement in the hotel’s staff canteen.
Although this area is often overlooked in luxury hospitality, it plays a key role in employee well-being.
Due to the low ceilings and limited duct space, the team selected bipolar ionization as the primary purification technology.
They integrated it directly into the plenum boxes above the ceiling diffusers, ensuring both high efficiency and discreet operation.

A Flexible Solution for Complex Environments

This case study highlights a critical yet often-overlooked truth: each building requires a tailored approach to indoor air quality (IAQ). Consequently, Marquis Intelligence developed custom solutions instead of applying a one-size-fits-all system.

Even within a single building, different areas require different approaches based on architecture, function, and occupancy.

It means that what worked for the guest rooms couldn’t be applied to the canteen.
On the other hand, what suited the ballroom didn’t fit the rooftop bar.

Marquis Intelligence developed each solution with technical precision and visual harmony. This ensured that the aesthetics and comfort of five-star hospitality remained untouched.

>>See also: Top 5 Projects of Marquis Intelligence in 2024

Long-term Partnership, Long-term Care

The Marquis Intelligence service team provides complete maintenance for all IAQ systems at the Hilton Belgrade Hotel. Regulation, hygiene monitoring, and technical maintenance ensure the air remains consistently exceptional, just like the guest experience.

This article is part of the Marquis Intelligence “Mini Case Studies” archive.
Document ID: MI-MCS-01.2Q-25.
Name of the document: Mini Case Study: Hotel Hilton Belgrade

The post Mini Case Study: Hotel Hilton Belgrade appeared first on Marquis Intelligence.