How Quickly Do Electronic Devices Become Contaminated? Faster Than You Think

Electronic devices may be the most-touched surface we’re not cleaning

Let’s picture some high-touch surfaces: light switches, doorknobs, handrails, desks and phones. These surfaces are considered high-touch for a reason: multiple people touch them multiple times per day (and in some cases, per hour). Research has attempted to uncover how quickly these high-touch surfaces are re-contaminated, with some studies indicating it may occur within a few hours to a few days after cleaning and disinfecting.^1-2

Now let’s picture how often people interact with phones and computers. Office workers spend most days on their laptops. The average American spends more than 5 hours per day looking at their phones alone.³ Additionally, screens play a bigger role in how we order food and shop in stores.

Because we frequently touch electronics, they may be an important vector for transferring contamination from place to place. We may move bacteria from our phones and computers to shared surfaces, and we pick up contamination from those surfaces that ends up on our phones and computers. While many public spaces and surfaces are cleaned daily, our phones and laptops typically are not cleaned.

Cell phones may be 10X more contaminated than a toilet seat⁴

We conducted a study of office workers to see how dirty their cell phones and laptops were.

In our study, 52% of adults admitted to only cleaning their electronic devices once per month. 7% said they had never cleaned their devices. This suggests that the majority of people do not clean their devices regularly. When we tested devices for bacterial contamination, it showed 25% of devices tested positive for Staphylococcus bacteria:

• The average device had more than 2,000 colony forming units (CFU) of bacteria — that is 10 times germier than a toilet seat⁴
• The dirtiest devices had 24,000 CFUs — or 100 times dirtier than a toilet seat!

We touch laptops and cellphones frequently, and after touching them people tend to touch other surfaces around them: desks, conference room phones and equipment, break room surfaces and microwaves. Electronics may be the highest-touch surface in an office – and one of the largest contributors to contamination of every surface.

Sanitizing devices is an effective way to reduce bacterial contamination — but we need to do it regularly

In our same study, we sanitized each device with a sanitizing wipe designed for screens and measured the contamination again after meeting the recommended contact time. Across all devices, bacterial contamination dropped significantly after sanitizing — even on the laptop with over 24,000 CFUs! Also, none of the devices tested positive for Staphylococcus after using the sanitizing wipes, highlighting how effective sanitizing electronic devices can be at reducing illness-causing germs.

But how quickly does bacterial contamination return? We investigated this, too. After we sanitized the devices, we asked everyone to take them, use them like normal and return one day later for contamination testing. We found that cell phones had been completely re-contaminated within just one day. Laptops were close — they showed half of the original contamination level. We expect that within two days laptops would be completely re-contaminated.

To help prevent the spread of illness-causing germs on high-touch surfaces, people need to sanitize their devices

Many people are not cleaning and sanitizing their devices at all. And even if they do, our research found that re-contamination happens fast — within 1 day after sanitizing! We recommend everyone sanitize their devices at least once per week, or more frequently if the devices are shared between multiple people or if there are illnesses spreading in the workplace, since germs may be transferred from devices to other shared surfaces.

For office managers and cleaning managers, we recommend providing sanitizing wipes to employees and encouraging them to sanitize their devices to help prevent the spread of illness-causing bacteria on other high-touch surfaces. Learn more about our latest innovation, Clorox Screen+ Sanitizing wipes: a product solution designed for electronics that you can provide in offices you manage or clean.