A virus outbreak at any location demands an immediate response. Whether it involves an office, healthcare facility, vessel or sports centre, rapid and targeted action is essential as soon as a virus begins to spread. In these situations, standard cleaning is simply not enough. What is required is professional disinfection: a specialised treatment that eliminates bacteria, fungi and viruses at a microscopic level.
In this article, we explain what professional disinfection involves, how the process works and when calling in a specialist is the only responsible choice. We also share real-life examples, including the recent disinfection of the expedition vessel Hondius in Rotterdam following an outbreak of hantavirus.
What is professional disinfection and when is it needed?
Cleaning and disinfection are two different processes. Cleaning removes visible dirt from surfaces. Disinfection goes a step further by eliminating harmful microorganisms on surfaces as well as in the air. Following a virus outbreak, disinfection using non-professional products and methods is rarely sufficient.
Professional disinfection is recommended in situations such as:
- A confirmed or suspected virus outbreak at a location
- Reopening an area after a contamination incident
- Preventive treatment of high-risk environments such as healthcare facilities, hospitality venues or public transport
- Disinfection of vehicles or vessels following a hygiene incident
- Situations where standard cleaning protocols do not provide sufficient assurance
Professional disinfection combines certified products, specialist equipment and highly trained personnel. This combination delivers the level of reliability required in critical situations.
The method: hydrogen peroxide for effective virus control
At EWS Group, professional disinfection is based on a hydrogen peroxide fogging technique. Hydrogen peroxide is known for its broad-spectrum effectiveness against bacteria, fungi and viruses without damaging surfaces.
What sets this method apart from conventional approaches is the way it works:
- The active substance is dispersed as a fine mist using specialist equipment, allowing even hard-to-reach areas to be treated
- The disinfectant remains active on all contact surfaces throughout the required contact time
- Once the contact time has elapsed, the area is ventilated and the hydrogen peroxide naturally breaks down into water and oxygen
- No harmful residues are left behind
This approach makes the treatment not only highly effective, but also safe for use in offices, healthcare facilities, food environments and transport vehicles. Test results show that the treatment eliminates up to 99.9% of microorganisms present.
Difference from standard cleaning
| Standard cleaning | Professional disinfection |
| Visible surfaces | All surfaces and the air, including hard-to-reach areas |
| General-purpose cleaner or disinfectant | Certified H2O2 solution |
| May leave chemical residues | Breaks down into water and oxygen |
| Limited effectiveness | Eliminates up to 99.9% of microorganisms |
| Cleaning staff | Specialised, certified personnel |
How does a professional disinfection treatment work step by step?
An effective treatment requires preparation, execution and verification. Below are the standard steps followed by EWS Group.
Step 1: Define the treatment area
All areas to be treated are identified in advance, including adjacent areas where access will be temporarily restricted. This helps minimise the risk of cross-contamination.
Step 2: Prepare the location
Before the treatment begins, several preparations must be made. Food and medicines must be removed from the area. Electronic equipment must be switched off. Moisture-sensitive items such as paper documents or artwork should be removed. Kitchen utensils and crockery must be stored away. Fire alarms are temporarily disabled or covered, and positive-pressure ventilation systems are adjusted where necessary.
Step 3: Fog the disinfectant solution
The treatment is carried out by trained personnel wearing appropriate personal protective equipment (PPE). The fogging process distributes the disinfectant evenly throughout the area, including locations that are difficult to reach by hand.
Step 4: Contact time
After fogging, the treated area remains inaccessible for up to one hour. The exact duration depends on the ventilation conditions and the specific location.
Step 5: Ventilation and verification
Once the required contact time has elapsed, the area is ventilated. The hydrogen peroxide mist dries and naturally breaks down. Air quality measurements are then carried out. The area is only officially released for use once the measured values comply with the applicable safety standards.
Case studies: from GP practice to cruise ship
The method can be applied in a wide range of situations. The following two examples demonstrate how widely the method can be applied.
Healthcare facility during COVID-19
During the COVID-19 outbreak, a GP practice in the Dutch town of Geertruidenberg engaged EWS Group to disinfect a dedicated treatment room. The aim was to create a safe environment for (potential) COVID-19 patients, without putting doctors or other patients at risk. Read the full story in our case study on disinfecting a COVID-19 treatment room in a GP practice.
Cruise ship following a hantavirus outbreak
In May 2026, EWS Group carried out the disinfection of the expedition vessel Hondius, which had been berthed in Rotterdam following an outbreak of hantavirus (Andes virus). The vessel had to be completely free of the virus before the crew could disembark and the ship could return to service. Projects like this demonstrate how professional disinfection can be applied at large and complex locations, while following strict protocols for access control, ventilation and safety measurements.
Both case studies highlight the scalability of the method, from a single treatment room to a floating hotel with dozens of rooms.
Industries where professional disinfection should be standard practice
Virus outbreaks are not limited to a single type of location. Disinfection following an incident, as well as preventive treatment, is relevant for:
- Healthcare: hospitals, GP practices and nursing homes
- Maritime and transport: vessels, terminals and vehicle fleets
- Hospitality and leisure: hotels, restaurants, gyms and cruise ships
- Facility services: office buildings, schools and municipal buildings
- Food industry: production facilities and storage areas
For more information about our professional disinfection services, visit our professional disinfection service page.
Frequently asked questions
What is the difference between cleaning and disinfection after a virus outbreak?
Cleaning removes visible dirt from surfaces. Disinfection goes a step further by eliminating harmful microorganisms on surfaces as well as in the air. Following a virus outbreak, cleaning alone is not sufficient. Professional disinfection using certified hydrogen peroxide-based products is required to safely release a location for use.
How long does a professional disinfection treatment take?
The duration depends on the size and type of location. A single office can often be treated and released within a few hours, while a larger site such as a vessel or production facility may require several days. Following fogging, the required contact time is up to one hour, after which the area is ventilated and air quality measurements are carried out.
Can the area be used immediately after treatment?
The area is only officially released once air quality measurements confirm that the results comply with the applicable safety standards. This is a standard part of EWS Group’s protocol.
No assumptions are made; the measurements determine when the area can be safely returned to use.
Which locations are suitable for professional disinfection?
The method can be used in a wide range of environments, from healthcare facilities and offices to kitchens, sports facilities, transport vehicles and vessels. As long as the necessary preparations have been completed and the area can be temporarily closed off, the treatment can be carried out.
What preparations should I make before the treatment?
Remove food and medicines, switch off electronic equipment, store away kitchen utensils and remove moisture-sensitive materials. EWS Group will take care of the rest and guide you through the preparation process.
Treating a virus outbreak involves more than cleaning
A virus outbreak requires more than an extra round of cleaning. Professional cleaning and disinfection, carried out using the appropriate products and methods, is the only reliable way to safely release a location following a contamination incident. Whether it concerns a treatment room, an office building or an ocean-going vessel, the approach is essentially the same, and the results are measurable and verifiable. EWS Group provides professional disinfection services across a wide range of industries. Would you like to find out how we can help protect your location following a virus outbreak or as a preventive measure? Contact one of our specialists.
