Disinfecting Spaces for COVID-19

Dec 28, 2020 at 09:48 pm by pj




As medical professionals, you’ve likely been inundated recently by advertisements touting products that will disinfect spaces of SARS-CoV-2 (COVID-19) and other infectious diseases. While we’ve all had to up our game during this recent pandemic, by either adding products to our repertoire or increasing the use of disinfectants we have on hand, it’s important to make sure that we’re not fixing one problem only to create other problems in the process with our choice of disinfectants. Choosing the best form of disinfection doesn’t have to be difficult, and with the right information and knowledge, you can make an informed decision now that you won’t regret later. Let’s play a game to test that knowledge...


True or False?


Whole-Space Disinfection Reaches Everywhere

True—And we’ve based our entire company on it. But, it’s important to understand that not all disinfection systems are the same. 

What you commonly see advertised as “fogging” is actually electrostatic spray. This technology often claims to reach “everywhere” at the same time it advertises a targeted delivery. However, you can’t have it both ways. Either the disinfectant completely fills the space, or it only kills germs on the surfaces where it is aimed. There are times when targeted spraying is ideal due to the difficulty of enclosing a space or due to the fact that the space is so large (like an auditorium) that it makes it difficult to fog. But when possible, engulfing an environment in true vaporous fog is the most effective. Fogging allows vapors to reach every nook and crevice of a space, including all of the room’s contents. For example, CURIS’ hybrid hydrogen peroxide™ (HHP™), a combination of aerosol and vapor hydrogen peroxide, has been validated at 21ft. high and trusted in healthcare environments, such as hospitals, ambulances, and other medical facilities throughout the United States. It has revolutionized disinfection practices and cleaning protocols, changing expectations of germ safety from “attempts to just clean better” to an achievable, measurable kill result of dangerous germs.* 


Spraying Means I Don’t Have to Evacuate the Room

False—Ok, we’re not talking about a few squirts from a spray bottle here. But anything more than that is cause for serious consideration, e.g., electrostatic sprayers or other volume spray devices.  Whether it is bleach, peroxide, or your favorite name-brand solution, there are strict OSHA limits for what is considered safe for exposure. Just because it smells “clean,” doesn’t mean it is safe. For example, bleach has a limit of 0.5 ppm TWA 8 hrs, which is too much to explain here, but suffice it to say, if you smell it strongly, you probably shouldn’t have patients staying in the room, and it may be unhealthy to breathe in while cleaning with it. The point is, if someone advertises that you can use an industrial sprayer while staff or patients remain in the space, you might want to think again and check the active ingredient for OSHA requirements.  Systems that allow for remote, hands-free operation are the safest and can even reduce human error while allowing the operator to remotely monitor, manage, measure, track, and report decontamination efforts.


If the Label Says It Kills the “Germ,” then It’s All Good

False—Because you may inadvertently be creating pathogen reservoirs or causing corrosion from the disinfectant you are applying. One of the common ingredients that makes many disinfectants so effective is also the same ingredient that makes them sticky, messy, and corrosive. Ammonium chlorides (Quats/Quacs that are not usually prominently listed as an ingredient but are still there) often help chemical solutions achieve a 99.99 percent kill rate. But if not quickly wiped off, they leave a residue that can build up on a surface, capture grime, retain additional ingredients, such as chlorine dioxide, on the surface that cause corrosion and even unknowingly create a haven for colonies of pathogens to grow. Unfortunately, these adverse effects (rust, corrosion, and sticky messes ruining expensive equipment) have become a known negative side effect as increased frequency of treatments has become necessary during this pandemic.


Killing 99.9 percent is Effective Enough

Maybe true, but it depends on your goals—We are firm believers at CURIS® that catching a cold or stomach bug every once in a while can help most people maintain a healthy immune system. However, when dealing with a pandemic or when operating a medical practice where patients may be immunocompromised, there is no room for pathogens left behind. You may or may not have heard of log reduction. This simply refers to how many 9’s after the decimal point a disinfectant can claim. If it kills 99.9 percent of a pathogen like Influenza, then there can be up to 1,000 viable organisms (germs) left behind on just that one spot. If a disinfectant kills 99.9999 percent, then less than 1 (you can never say 0) organisms are left behind. Why does this matter? Sometimes, depending on the pathogen, it only takes 1–10 viable organisms to make you sick.  In the case of SARS-CoV-1 (we don’t have the numbers yet for SARS-CoV-2), only 67 organisms (germs) can possibly make someone sick. Knowing that, how many 9s do you need for your disinfectant? The only acceptable number to us is 99.9999 percent. 


UV Light is Fast and Can Disinfect a Room in 10 Minutes

False—Disinfection implies a 99.99 percent kill rate, and most industrial UV lights achieve only a 99 percent or 99.9 percent kill in 10 minutes or less. UV light can be a useful tool, but if you’re treating a whole room or object, the time needed to really disinfect is between 30–40 minutes. This means the light will disinfect only where light touches for as long as the light is stationary in that position for 30–40 minutes. Yes, that means if you are using UV light, you need to move the light to a new position every 30–40 minutes, and it may actually take 1–1.5 hours or more to effectively disinfect a patient room with a bed.

So, what’s so great about true whole-space disinfection fogging? 

Simply put and most importantly, fogging is the most effective disinfection, as it reaches everywhere air touches. It kills germs in every nook, cranny, and crevice that wiping or spraying often miss. With a high-level, EPA-registered sporicidal disinfectant fog, you can feel confident that you are using the most effective disinfection system available, and with the right systems and protocols, you can change expectations of germ safety from just “cleaning better” to achievable, measurable kills of dangerous germs.  

The best whole-space fogging leaves no harmful residues. It engulfs a space with powerful disinfectants like hydrogen peroxide that decompose to harmless water and oxygen.

Ideal whole-space disinfection systems keep surfaces “wet” enough to kill germs without soaking or damaging surfaces. 

True whole-space fogging is also faster. If you factor in the time it takes to properly spray every surface, let the disinfectant stay wet as directed (dwell time), and then wipe it off, your staff will spend equal or more time than fogging takes. 

And lastly, ideal whole-space fogging is safer to use. With remote operation, neither staff nor patients are exposed at any time to dangerous chemicals. 

So the bottom line is that, while there are various solutions and systems available that claim to fight infectious diseases in spaces and on surfaces, it’s important to remember that there may be hidden truths, misleading information, and unfortunate side effects. Understanding the differences is key to achieving the highest rates of effectiveness, safety and overall ease of use.   


*C. diff in a tri-part soil load


Frances M. Grinstead, CEO, CURIS System, has been working in bio-decontamination for over a decade and has been at the forefront of innovation in high-level disinfection in high traffic facilities. As the first to develop a truly portable decontamination device and the first to establish a bio-decontamination service for the purpose of outbreak control, she has created a market that others now emulate, all in an effort to improve innovation and understanding of infection prevention and control. She develops and implements fact-based programs to minimize risks, helping prevent the spread of infectious disease. Visit www.curissystem.com