Case study - Proven improved hygiene efficiency by deploying a 24-hour disinfectant

24-hour disinfectant case in schools 24-hour disinfectant case in schools

How a 24-hour disinfectant helps build healthier and safer learning environments



On a daily basis, most schools ask the students to move from one classroom to another several times a day in order to take different subjects.

Because of that, each desk is shared by many students throughout the day.

Cleaning and disinfecting desks, chairs, and teaching equipment after each and every usage is virtually impossible.

The challenge of keeping those areas clean and hygienic and preventing the transfer of pathogens is a concern for the incumbent cleaning company. 

Long lasting disinfectant case in a school in Finland

Cleaning companies need to balance budgets - especially in today’s economic climate, with difficulties in staff recruitment and retention, operational pressure, and seasonal outbreaks - for example, cold and flu coupled with the ongoing Covid-19 pandemic. 

Cleaning companies need efficient cleaning and disinfecting products that enhance the well-being of children, students, and adults using educational facilities. All high-touch areas need to be disinfected after they have been cleaned. However, microorganisms start to repopulate these touch points (for example desks, chairs, railings) soon after they have been touched a number of times, with levels quickly rising to a point that would cause concern!

The question posed is: "How is it feasible to reduce and, where possible, eliminate pathogens in high-traffic areas used continuously, 12 hours a day or more?"



Diversey developed Degragerm 24™ Shield 24-hour disinfectant, an innovative cleaner, and disinfectant with residual (persistent) efficacy.

This product provides initial efficacy against bacteria, yeasts, and enveloped viruses (according to European Norms (EN) standard testing), plus 24-hour residual efficacy against enveloped viruses and bacteria according to PAS2424.

The PAS2424 test method, developed by the British Standards Institute, is the preferred test method for Europe used in the United States and is qualitatively similar to the EPA RSS test method in that it tests both multiple abrasion cycles and multiple reinoculations and both tests have a 3 log reduction target.

Degragerm 24™ Shield works through the biocidal active ingredient, quaternary ammonium compound (Quat), which is bound in a unique polymer film (APT- Advanced Polymer Technology).

In Degragerm 24™ Shield , the Quat is held loosely so that the biocidal active ingredient is released relatively quickly over 24 hours. This unique technology allows the Quat to penetrate through soil accumulated in high-touch areas and provide strong residual disinfecting efficacy over a 24-hour time period.

It is this that differentiates Degragerm 24™ Shield from any other product on the market that claims residual efficacy. For all of these reasons, this was the ideal product to meet the cleaning company’s operation requirements, even when the surface is repeatedly touched after the initial disinfection. Degragerm 24™ Shield was applied in a field test evaluation by one of the largest cleaning companies in Finland, and they chose to conduct this test in a school environment.


Test Method

The school selected for testing has several classes that are attended:

• During the day, by 7th-9th grade students

• Evening classes attended by adults/children

Two classrooms were selected and in each classroom, the following key surfaces were selected:

• x4 desks

• x4 chairs

• x1 indoor classroom handle

• x1 outdoor classroom handle

These touchpoints were swabbed (Orion's Hygicult TPC). The swabbing system was incubated using standard methods to assess the microbial growth on the above-mentioned test surfaces and was sampled at three time points.

A. Before cleaning the surfaces (after completion of evening classes)

B. Immediately after cleaning the key surfaces with a microfiber cloth (after the allowed disinfection contact time)

C. 20 hours after the initial cleaning and disinfecting of key surfaces with Degragerm 24™ Shield.

24 hour disinfectant case in a school in Finland


The results of the testing were categorized as follows:

1. Low - containing 1-5 CFU*/cm²

2. Medium - containing 45-80 CFU*/cm²

3. High - containing >100 CFU*/cm²

*CFU: Colony Forming Units


Test results

The results significantly demonstrate the disinfecting and residual properties of Degragerm 24™ Shield. applied to the test criteria.

Degragerm 24 Shield test results


Both cleaners and supervisors that compiled this field test commented on the performance of Degragerm 24™ Shield:

"It was very easy to apply this product and after application, the surface looked bright and clean and it felt like no chemicals had been used. It is also great that the treated surfaces did not need to be rinsed off after application as there was no build-up. On top of all these benefits, Hygicult's results were exceptional even 20 hours after the surfaces were applied and used!"

Degragerm 24™ Shield makes cleaning and disinfection as well as the protection of the surfaces an easy task but also offers excellent compatibility with most surface materials.

It helps by providing peace of mind for end-users (i.e. teachers and students) as the surfaces are safe to touch, but it also helps by reducing absenteeism among students, teachers and the rest of the staff by reducing the risk of contamination.

The results also indicate that Degragerm 24™ Shield's persistence benefits over a 24-hour period deliver operational advantages by reducing application time, and product usage but more importantly labor savings, especially in today’s economic climate and the hardship of staff recruitment, staff retention, and difficulties in training. Using Degragerm 24™ Shield can help reduce the amount of waste produced, which is great news for the environment and all of us.


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