Can Frequent Use of Disinfectants Lead to Surface Damage?
As 2021 rolls around, the U.S. is still in the middle of the COVID-19 pandemic. And just like for most of 2020 we’re likely to continue doing a lot of cleaning and disinfecting in public and private spaces than prior to the pandemic. As a result, people are asking about the effect of more frequent cleaning and disinfecting on common surfaces such as tables, chairs, school desks, countertops, door handles and light switches, and other “high-touch” surfaces.
So what are the issues with extended and frequent use of disinfectants on plastics, metals and other hard, nonporous surfaces, how can they be addressed, and what’s the difference between surface damage, and residue left behind after cleaning and disinfecting?
Let’s start with the easy one — residue. Most household or commercial disinfectants are water-based. They contain an “active” ingredient which might be a quaternary ammonium chloride, or “quat,” sodium hypochlorite (better known as bleach) or hydrogen peroxide, that kills pathogens. Small amounts of other ingredients are often added; detergents to help with cleaning, special additives to control stability or improve antimicrobial efficacy, and organic solvents to help keep everything in solution and improve performance. After a cleaner or disinfectant applied to a surface has dried, some of these ingredients will be left behind on the surface.
The type, color and texture of the surface material will determine what the residue looks like on the surface. If the disinfectant spreads out evenly on the surface or the surface is textured, the residue may not be easy to see or the surface may appear a little dull. On a smooth surface the disinfectant may form small beads which dry to leave visible spots or circles. If the surface isn’t wiped after application, the residue can build up and appear unsightly. In these situations, you should be able to remove the residue by wiping the surface with a clean damp cloth. You can do this after the contact time has been reached, or periodically — say every few days. You should see no visible change to the surface if the disinfectant hasn’t caused any damage.
Occasionally, after cleaning a surface for an extended period, it may start to look dull or pitted, or you may see hairline cracks on the surface. These are all signs of permanent damage which may have been caused by a frequent use of a cleaning and disinfectant product. While disinfectant manufacturers try to formulate products that won’t cause damage to most hard, nonporous materials, they must balance this with the need for rapid pathogen kill, ease of use, safety and cost. In healthcare settings, where surfaces, medical devices and equipment are frequently cleaned and disinfected, the risk of material damage has been an issue for many years. This issue of “surface compatibility” of the disinfectant is now coming to the forefront in other types of facilities such as schools, colleges and offices which are now being cleaned and disinfected more thoroughly and more frequently.
Surface compatibility is typically described in black and white terms: “This disinfectant is not compatible with this material” for instance. But it’s not that simple. A disinfectant could be used on a surface for many years with no apparent damage to the surface. In other cases, extended use may result in some minor damage — seen as pitting, dulling or tarnishing. This may affect the look of the surface but the structural properties of the material may not be affected. In extreme cases, damage in the form of cracks in plastic materials or corrosion on metals affects the look of the material and indicate that material integrity has been affected. Surface damage not only affects the looks of the material but can also make it harder to clean and disinfect a surface properly.
What you can do to reduce the risk of surface damage?
When disinfectants are used regularly, it’s important to balance the benefits of their efficacy against pathogens versus the risk of potential damage to materials and surfaces. Fortunately, users can take several steps to reduce the risk of surface damage.
- Look at the equipment manufacturer’s cleaning and care guidelines for how to clean and disinfect surfaces. These often include guidance on what types of products can be used and how. If there are no guidelines, contact the equipment manufacturer to discuss care and maintenance.
- Disinfectant manufacturers are increasingly issuing guidance on compatibility of their products with common hard surface materials. Look at their websites or contact them to see what products are compatible with different types of surface materials.
- Just as with residue, wiping with a clean damp cloth to remove excess disinfectant reduces the risk of damage. Depending on the surface material and disinfectant, wiping may need to take place after each cleaning; in other situations, removal every few days may be enough.
As you continue to work hard to provide your customers with healthier and safer environments, factors including the type of surface materials being cleaned, the importance of surfaces looking clean as well as disinfected, and the risk of not disinfecting versus potential damage will all need to be considered. The good news is that there are a few steps you can take to eliminate residue and reduce the potential for surface damage, while keeping the facility environment clean, disinfected and safe.