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High-touch surfaces in hospitals must be disinfected daily to maintain a sanitary environment. Cleanliness can be assessed by measuring environmental cultures, fluorescent markers, and/or ATP (adenosine triphosphate) levels. Many hospitals use ATP levels, measured in relative light units (RLUs), to gauge surface cleanliness since results can be obtained in 15 seconds giving instantaneous feedback. An example of  accepted ATP levels are < 25 RLUs for general hospital surfaces and < 10 RLUs for operating room surfaces. Even with disinfection, ATP levels can reach 10,000+ RLUs in high-touch areas between daily cleaning!

Healthcare-associated infections (HAIs) are a known risk to patient and employee safety in hospitals and transmission of these HAIs is related to contaminated surfaces and equipment. On average, each HAI costs the hospital about $16,000 which is not covered by insurance. However, regimented disinfection efforts are linked to a reduction of bacterial transmission and control over HAI outbreaks.

Cleaning procedures vary from hospital to hospital but an example cleaning procedure is as follows:

  • Disinfect high-touch surfaces (general disinfectant cleaning)
  • Measure ATP level to confirm it is below required level
  • Disinfect surface again 12-24 hours later

What happens on surfaces between cleanings? This graph is showing time on the x-axis and ATP levels (adenosine triphosphate levels) on the y-axis. The green zone is the acceptable zone – what hospitals generally consider acceptable ATP levels. The red zone is the unacceptable zone – what hospitals generally consider unacceptable ATP levels due to the potential unsanitary conditions for patients and employees.

Each day, after the daily cleaning and disinfection in the morning, ATP levels are measured to confirm that the surface passes hospital cleanliness protocols. Those pre-clean ATP levels are shown by the green circles in the graph on the left. All these measurements are in the green acceptable zone which means the disinfection procedure was thorough and effective. As time goes by throughout the day, people touch and interact with the surface. The ATP levels begin to rise, slowly at first, and then surge quickly above the acceptable level.

Microbes are living organisms so they are going to grow and multiply throughout the day causing the ATP levels to surge into the red unacceptable zone as shown by the green dotted line in the graph on the right. The ATP levels continue to climb exponentially until the daily cleaning and disinfection the next morning. ATP levels before the next disinfection are shown as “X”s. Surfaces with ATP levels in the unacceptable zone between the daily disinfection are cause for concern as they can lead to unsanitary conditions for the patients and the employees.

Let’s examine what the surface looks like during this process. First, we’ll start with an unclean surface before the daily disinfection. If we zoom in on this surface and take a look at it from the side view (1), you’ll notice that the surface is microscopically rough and uneven. All surfaces have some level of surface roughness or porosity – this is common.

Next, the surface is disinfected which removes most of the microbial growth (2). You’ll see that some microbes, however, remain hidden in the crevices on the surface. Since microbes are living organisms, these hidden microbes grow and reproduce throughout the day. In addition to that microbial growth, people are regularly interacting with the surface depositing more microorganisms. Together, the growth of existing microbes and deposition and growth of new microbes, leads to an exponential rise in ATP levels (3). These ATP levels surge into the unacceptable zone until the surface is disinfected again the next day.

XYLEX® Protect was developed to specifically address the need to prevent uncontrollable surge of ATP levels between daily cleaning and disinfection.

What can we do to keep ATP levels low around the clock on high-touch surfaces? The first thought is to increase the frequency of surface cleanings/disinfections. By increasing cleanings, we can minimize the microbial growth on surfaces so the ATP levels stay in the acceptable zone. However, by increasing the frequency of cleanings, we also increase the time required for cleaning, the number of employees needed to perform the cleaning, and the necessary supplies. This is a considerable cost increase for the hospital.

Another option is to create a protective barrier layer on the surface that can effectively prevent ATP surges. This is the exact technology behind XYLEX® Protect It creates an invisible molecular barrier on the surface which makes surfaces smoother and more difficult for organic residue to adhere. XYLEX® Protect is easy to apply, takes an extra 5-10 minutes per month, and no additions to the cleaning crew. This augmented technology is cost- and time-effective and provides an extra layer of protection to high-touch surfaces.

Let’s go through 24 hours on a regular, unprotected surface. After the surface is cleaned with a regular disinfectant, ATP levels (shown on the y-axis) are low in the acceptable zone. Throughout the day, people interact with the surface – touching the surface, coughing on the surface, depositing bacteria onto the surface. As we know, microbes grow and multiply over time so we see the ATP levels can surge into the unacceptable zone. The microbes continue to grow on the surface until the surface is cleaned again the next day.


Now let’s examine a surface that is treated with XYLEX® Protect. The surface is cleaned with a general disinfectant to start resulting in low ATP levels just like the untreated surfaces. Throughout the day, people interact with the surface – touching the surface, coughing on the surface, depositing organic residue onto the surface – but here is where XYLEX® Protect makes that big difference. The barrier created by XYLEX® Protect makes it more difficult for organic residue to adhere to the surface, so we do not see that ATP surge as time progresses! The ATP levels stay within the acceptable range throughout the day and night. During the daily clean the next day, the surfaces are cleaned and disinfected much more effectively due to the smoother surface and less residue accumulation on the surface.

This product does not protect users or others against bacteria, viruses, germs or other disease organisms.