Workplace exposures

Responding is Pat Swisher, president, Enviro-Master, Charlotte, NC.

Cross-contamination is the spreading of bacteria and viruses from one person or surface to another. Bacteria and viruses are known to spread through the nose, mouth and hands to others, but did you know that cross-contamination also can begin in the restroom?

Each time a toilet is flushed, thousands of particles are ejected into the air and land on surfaces, such as the fixtures, floor and partitions. If these particles are not removed properly they will remain in a warm, moist environment, allowing for bacteria and viruses to breed. One person coming in contact with the bacteria is all it takes for cross-contamination to occur.

According to an interview PBS conducted with Kelly Reynolds, microbiologist at the University of Arizona, it takes only four hours for a virus to spread in the workplace.¹ Reynolds and her team targeted a fairly small workplace and put a “surrogate virus” into a droplet of water. Then they had one random participant rub the water into their hands. The researchers asked study participants (all of whom were unaware of which participant’s hands carried the virus) to commence their workday activities. Four hours later they swabbed “commonly used surfaces.” The results showed that half of the surfaces and “half of the hands of the co-workers tested positive for the virus that [they] planted.” Reynolds also pointed out that “it’s much more likely that you’ll come into contact with somebody else’s germs from a contaminated surface, because the viruses in [coughs and sneezes] just don’t stay in the air very long. They tend to settle on surfaces. And that’s where they survive for hours to days. And so you’re much more likely to pick up a germ from where that person has coughed even though you don’t even realize you’ve come into contact.” Therefore, cross-contamination has a higher probability of occurring via contaminated surfaces than coughs and sneezes.

However, the challenge of controlling cross-contamination lies in the hands of workers. According to the Center for Disease Control and Prevention, the best way to control the spread of disease is through good health habits. Avoid contact with people who are sick; stay home when you are sick; cover your mouth and nose when coughing or sneezing; wash your hands frequently; avoid touching your eyes, nose and mouth with your hands; and – last but not least – clean and disinfect surfaces.² This is sound advice and should be followed on a regular basis, but as Reynolds pointed out, “We get a little too lazy about things, we forget.”¹ So, how can we be sure that our areas are thoroughly disinfected?

First and foremost, have a hygiene company that specializes in disinfecting public facilities decontaminate the facility on a weekly basis. Hiring professionals who are trained to disinfect all contaminated surfaces, starting with restrooms, greatly reduces cross-contamination. Your employees’ health is of the utmost importance.

1. Bowser, B. (2013, March 7). How Quickly Do Germs Spread in the Office? Retrieved March 16, 2015, from www.pbs.org/newshour/rundown/how-quickly-do-germs-spread-in-the-office/.
2. Stopping the Spread of Germs at Home, Work & School. (2014, September 4). Retrieved March 16, 2015, from www.cdc.gov/flu/protect/stopgerms.htm.

Editor's note: This article represents the independent views of the author and should not be construed as a National Safety Council endorsement.