From crowded hospital waiting rooms to busy elementary school classrooms, surfaces that look clean might be harboring disease-causing pathogens.
“Some people think if they clean a surface with soap and water, that’s fine. And that disinfectant is only needed when someone in the building is sick or if a surface is really dirty,” said Alice Brewer, senior director of clinical affairs for PDI, a manufacturer of infection prevention products (including cleaning and disinfecting solutions). “The reality is we can’t see what’s on surfaces; germs are invisible. We may not know it, but these surfaces may be spreading harmful germs, especially during cold and flu season.”
The solution for ensuring high-touch surfaces are as clean as they look is proper disinfection. To achieve this, it’s important to choose the correct disinfectant for your facility and carefully follow
the product directions.
Know your disinfectants
When you think about disinfectants, the active ingredients are usually the first thing that come to mind. The most common active ingredients include quaternary ammonium (quats), organic
acids (such as lactic or citric acids), alcohols, hydrogen peroxide, and bleach. “A typical disinfect will include an active ingredient to kill pathogens, along with inactive ingredients. The official term for inactive ingredients is an inert,” said Brian Leafblad, research and development senior manager for global business solutions at Reckitt Lysol Pro Solutions. “Inert ingredients are not involved in the actual germ kill but do something else, such as clean or provide color, fragrance, or hard-water tolerance.”
“Sometimes there are two active ingredients in a disinfectant,” said Kirsten Hochberg, senior clinical and scientific affairs specialist for CloroxPro. “They combine hydrogen peroxide with an acid, or sometimes quats with alcohol. These active ingredients work together to give disinfectants their power.”
Each active ingredient kills different types of organisms. “Some kill more than others,” Leafblad said.
The easiest organisms to kill are enveloped viruses. “An enveloped virus has a shell around the outside. If you can break the shell, or envelope, the virus bursts open and is susceptible,” Leafblad
explained. “Quats are a great choice for enveloped organisms. They will kill a lot of different types of organisms, so if you need a general-purpose disinfectant, quats are fantastic for that.”
The most difficult pathogens to kill are bacterial spores, such as those that cause C. difficile. “Most facilities don’t need to worry about C. diff, but if you’re in healthcare, where it’s more of concern,
quats are not strong enough to kill C. diff,” Leafblad said. He and Brewer recommended disinfectants with a sporicidal, hydrogen peroxide, or bleach.
Using a hospital-grade disinfectant is a good idea in some hospital areas, such as operating rooms. Disinfectants must have proven kill claims for Staph aureus, E. coli, and Pseudomonas
aeruginosa to be listed as hospital grade. However, infection prevention experts caution that choosing hospital-grade disinfectants is not necessary for most environments. “It’s more
important to choose a disinfectant that can kill the pathogens you are worried about in your facility,” Hochberg said, adding you can find product kill claims either on the product label or
through a link provided by the U.S. Environmental Protection Agency (EPA).
“Hospital-grade disinfectants are necessary in hospital areas, especially those that undergo regulatory inspections,” Brewer said. “In an office space or other areas where you are
more concerned about cold or flu viruses than bloodborne pathogens, quats and other lower-grade disinfectants are the best choice.”
Consider gentle, eco-conscious formulations
Make sure to consider the inactive ingredients as well when choosing a disinfectant that will be used around people with asthma and other respiratory sensitivities. “You’d want something
that doesn’t have alcohol or fragrance,” Brewer said.
“Disinfecting, in general, should not be done when children are present, but if it needs to be done during the school day, we would push for schools to use more eco-conscious disinfectants,”
Hochberg said, suggesting schools consider those listed as EPA safer choice or EPA designed for the environment products.
“In general, products with lower levels of volatile organic compounds (VOCs) are going to be better because you have less chemicals evaporating into the air for people to breathe,” said Leafblad. He said most manufacturers formulate their products to comply with low-VOC regulations in California, so check on the product label for a warning required by Proposition 65, which mandates that businesses must alert Californians about the risk of significant exposure to chemicals that are harmful to their health.
In daycares and other facilities housing infants and young children, disinfectants approved for food-contact surfaces are a safe choice. “Little kids like to touch everything and put things in their
mouths, so make sure you’re using a disinfectant that is approved for food-contact surfaces, following the rinse recommendations on the label and checking any toys that you disinfect are dry
before you put them back,” Brewer said.
If you use a disinfectant that is not labeled as safe for food-contact areas in an employee breakroom or other areas where people eat, Leafblad recommends rinsing the surface with potable water after you disinfect it.
Avoid common disinfecting mistakes
One of the most common mistakes people make when using disinfectants is not allowing them to stay on the surface for the recommended contact time (also known as dwell time). “If you spray a
disinfectant on a surface then immediately wipe it up, you are not allowing it to reach the contact time needed to kill the pathogens on the surface,” Hochberg said.
“People are notoriously bad at estimating time and are often in such a hurry trying to get their job done, they don’t allow enough contact time,” Leafblad said. “If the product you are using says it has a two-minute contact time, and in reality, you step away just one minute before wiping it up, the surface hasn’t stayed wet long enough.”
Even if your cleaning staff intends to follow the recommended contact time, they may not realize they must apply more disinfectant to meet the requirement.
“If the product dries before the contact time is over, go back and add some more, make sure it stays wet until the appropriate contact time is met,” Brewer said.
Another mistake is choosing a product with a contact time that will not work in your facility. If you need to quickly clean and disinfect surfaces in a high-traffic area, for example, a disinfectant
that requires a 10-minute contact time is not the best option.
“In this case, people are buying a product that can’t be used as a disinfectant for their situation,” Hochberg said. She recommended that facility managers consider an area’s traffic and how
long custodians have to complete a disinfecting task before they choose a product. Weather and humidity are other considerations.
“In my experience, most surfaces will dry after two to three minutes in a dry climate. In other climates it may take longer. And alcohol-based disinfectants dry really fast,” Hochberg said. “It depends on the product and the humidity in the air. If you’re in a climate where surfaces dry quickly, choose disinfecting wipes or a product with a very short contact time of two minutes or
less so you don’t have to sit there and babysit it until it dries.”
Another improper way to use a disinfectant is not following the dilution instructions for concentrated products. “If you’re cleaning a restroom and the product label says dilute one part disinfectant to 16 parts water, follow those instructions. Don’t just take the cap off, think ‘well if some is good, more is better’ and dump the product full-strength in a urinal,” Leafblad said.
“Some of the product efficacy goes down if you don’t dilute it properly as the water is necessary to help the disinfectant kill germs. You’re just wasting money and wasting product, and
potentially damaging surfaces with repeated use of too much acid.”
Leafblad explained that hydrogen peroxide is generally safer on surfaces than bleach, but many disinfectants that contain hydrogen peroxide are acidic. “The acid makes the disinfectant more
stable and you get better germ-kill efficacy,” he said. “But if you are using a concentrate rather than an RTU [ready to use], you need to dilute it and if you don’t, you’re adding too much acid to
the surface and may damage it.”
Disinfecting wipes are another product that people often use incorrectly. “Many people leave the package open; then when the wipes dry out, they think they can add water and make them
work again. But they will not work,” Leafblad said. “Or people think that if they use up a package of disinfecting wipes and there’s a bit of liquid on the bottom, you can stick a paper towel into it and make your own wipes. That will not work either.”
Spreading a disinfectant too thin is another common error. “A lot of times people will use just one disinfecting wipe on a really big area,” Brewer said, explaining that although this tactic
saves wipes, it dilutes the effectiveness of the disinfectant.
Finally, many people make the mistake of thinking every surface needs to be disinfected. According to Hochberg, disinfecting outdoor surfaces, such as park benches and playgrounds, is not necessary and just wastes time and products. According to Brewer, certain surfaces will not tolerate harsh disinfectants. To ensure a disinfectant is safe for the surface you intend to disinfect, Brewer recommended checking the product manufacturer’s website to determine which surfaces are compatible with the disinfectant.
“You can’t use any wipe on any surface,” said Brewer. “Some wipes are harsher than others and might cause pitting or streaking on countertops or other surfaces. Now these surfaces have grooves
and divots where bacteria can grow.”
Dismiss myths and misconceptions
In addition to using disinfectants improperly, many users also have false ideas about these products. Hochberg said she often hears people express doubts about the effectiveness of green disinfectants. “People are concerned that greener products won’t disinfect as well,” she said. “But an eco-conscious disinfectant goes through the same tests as a regular disinfectant to show efficacy.”
Another common misconception is that disinfectants with the same active ingredients are all the same. “People tend to lump disinfectants together, as in all bleach is the same,” Hochberg
said. “The formula of each disinfectant is important. You can modify the pH to make a disinfectant more effective against certain pathogens and add ingredients to the bleach to protect surfaces. Each individual product is different, even if the active product is the same.”
Leafblad said the COVID-19 pandemic sparked multiple misconceptions about the disinfecting process. “At the beginning of the pandemic there was a lot we didn’t know, and people started
disinfecting every surface all the time,” Leafblad recalled. “But there are reasons not to do this.”
Leafblad explained that by disinfecting too many surfaces, too many times, you can negatively affect your health. “People hear the word bacteria, and they get scared,” he said. “There is bacteria everywhere and not all of it is bad. There are tons of it in our digestive system that is beneficial. Just because there may be some bacteria on a surface, that doesn’t mean people will get sick from it. It’s just the disease-causing bacteria that is a concern.”
When determining whether to disinfect a surface, consider if people are likely to touch it. “For a germ to infect someone, it has to get into their body typically through their mouth, nose, or
eyes. If no one is touching a surface, it’s not worth disinfecting it,” Leafblad said.
Under the category of perceptions, rather than myths, people of different generations often have a different idea of what a clean and disinfected areas should smell like, Hochberg said. Older
generations might associate the smell of bleach with cleanliness while younger generations might gravitate toward the smell of lemons to signify cleanliness. However, the newest scent associated
with cleanliness is no scent at all.
Protect against chemical hazards
You not only have to protect surfaces against harsh disinfectants; you also must protect yourself. Read the product label for guidance on personal protection equipment (PPE) to wear when using
disinfectants. “Although the eco-conscious or safer choice disinfectants don’t require PPE, since you are doing a disinfecting task you should wear disposable gloves at a minimum, not just to
protect you from the disinfectant, but from the job you’re doing,” Hochberg said.
“Look at the manufacturer’s safety data sheet [SDS]. It will explain any hazard recommendations,” Leafblad said. “The most commonly recommended PPE will be gloves and safety glasses. The biggest risk is a splash hazard, as you are using it or diluting it. However, not all disinfectants are hazardous for your skin; it depends on the formulation.”
Whether you’re reading it to find safety guidelines or usage instructions, a disinfectant’s label may be its most important component.
“People have good intentions when they use a disinfectant, but they must follow the instructions for it to work right,” Leafblad said. “If they don’t follow the instructions, they’re not getting the
disinfectant they’re paying for.”
