Apparently, we wash our hands wrong 97% of the time

The process is simple. Water. Soap. Some soft scrubbing, while humming a 20-second-long “Happy Birthday” like many experts recommend. Follow it up by drying with a clean towel. You can do it right, but handwashing needs to be done at specific times to avoid the spread of bacteria.

The U.S. Department of Agriculture’s Food Safety Inspection Service (FSIS) just finished a study that examined how average test subjects handled handwashing while preparing food in the kitchen.

In the study, participants test-cooked a meal of turkey burgers and were observed to see how well they used food safety practices. Here are the top five mistakes witnessed:

Improper hand washing. Where handwashing was necessary to prevent cross-contamination of bacteria between food and food contact surfaces, 97% of participants failed to do so properly.

Cross-contamination abounds. What kitchen object was frequently observed to be exposed to cross-contamination? Spice containers. Other utensils and surfaces were exposed too, like refrigerator handles. FSIS notes that poultry pathogens like Campylobacter and Salmonella can survive there for between 4–32 hours. This kind of cross-contamination can occur when chefs don’t wash their hands after handling different food items.

Side dish struggles. Salads prepared alongside the burgers were exposed to bacteria by 5% of participants. Here, too, handwashing would have been necessary to prevent cross-contamination.

A useful tool. Despite the advantages of using a food thermometer to make sure meat is cooked to a safe internal temperature, 66% of participants did not use one. Instead, they relied on color and feel to figure out when the burgers were safe to eat, an unreliable method when compared to the concrete values given by a thermometer.

Not hot enough. A food thermometer is only helpful if you know what temperature you need to reach. Even when one was used, 45% of participants didn’t cook to a temperature high enough to kill bacteria — 165°F, in the case of turkey burgers and other poultry.

“You can’t see, smell or feel bacteria,” said FSIS’s Carmen Rottenberg. “By simply washing your hands properly, you can protect your family and prevent that bacteria from contaminating your food and key areas in your kitchen.”