Dwell Time: What Is It and Why Is It Important?

A dwell time, also known as contact time, is the amount of time a disinfectant must remain visibly wet on a surface to effectively kill a specific pathogen.

Too often we see people spraying a surface with a disinfectant and immediately wiping the disinfectant away with a towel. There is one major issue with this: the disinfectant was not allowed enough time to kill the targeted pathogen before it was wiped away.

While the intent is there, these bad habits lead to surfaces that aren’t disinfected at all.

What is an effective dwell time?

Dwell times vary by disinfectant and the intended pathogen being disinfected. They can range anywhere from 30 seconds to 15 minutes. You can find the dwell time listed on the disinfectant’s label or on the EPA’s website.

Fast dwell times are important when fighting viruses like COVID-19. A one minute dwell time means less time waiting for the disinfectant to do its job and more time protecting customers and employees.

Which disinfectants should I use?

Supply chains have been dramatically impacted and finding disinfectants with fast dwell times can be difficult. Household names like Lysol and Clorox make disinfectants that are effective, but dwell times are typically around 4 minutes or more.

Diversey Oxivir TB Wipes have a 1 minute dwell time for emerging pathogens such as COVID-19. When using disinfecting wipes, dry time is another important factor to consider. If the disinfectant drys before reaching the necessary contact time, it will need to be reapplied. Diversey Oxivir TB Wipes keep surfaces wet for the one minute required to thoroughly disinfect. If available, we recommend these wipes to our customers.

There are other great disinfectants that must be diluted with water. This type of disinfectant is commonly used for the towel and bucket method where you fill a bucket with the disinfectant accurately diluted with water and submerge microfiber towels.

These disinfectants are effective at disinfecting a variety of surfaces, however; they have a short shelf life once diluted. Read your labels and make sure to dispose of the disinfectant after the allotted time has passed.

Why are dwell times important?

Dwell times aren’t a suggestion, they are a requirement. The EPA performs numerous tests to prove the effectiveness of disinfectants. If your goal is to thoroughly disinfect a surface, you must let the disinfectant dwell for as long as the disinfectant’s label recommends.

Have more questions about dwell times? Leave a comment below.