Does Temperature Really Matter when Washing your Hands?
In January, I reviewed the changes to the 2022 Food Code in my blog (check out Part I and Part II), and one change to the food code that I had mentioned, but didn’t discuss in-depth, was the change that lowered the water temperature a hand sink was required to produce to 85°F, as noted in Section 2-202.12 of the code. This requirement has been in place since the publishing of the 2001 Food Code, which required a water temperature of 100°F. Prior to this, 110°F was required (see the 1999 Food Code). So why the change and does water temperature when washing your hands really matter?
The change started long before the 2022 edition was being developed. In 2010, the Conference for Food Protection had recommended changing the temperature to 85°F, but when the supplement to the 2009 Food Code was later released, the revision was not included.
As you look at the relationship between hand washing efficacy and water temperature…what we had always believed to be true was not supported by the research.
Growing up in the foodservice business, I had always heard the phrase “as hot as you can handle” when it came to the correct temperature to wash your hands. Many believe that the magical temperature at which hand washing should occur was 100°F. However, that is simply the water temperature that a hand washing sink should reach per the FDA Model Food Code, not necessarily the temperature at which you must wash your hands.
A few years ago, when we were getting ready to explore employee hand washing behavior as part of our research, this “requirement” came up as a discussion point among our research team as we were developing our observation rubrics. After digging into it, we realized that most resources online only said potable water, with no temperature requirement. Our team explored the websites of the Centers for Disease Control and World Health Organization and reviewed the food code to determine what was recommended and required. Outside of finding that food code required water at the sink to be a minimum of 100°F, there was no requirement to wash your hands at a certain temperature and no mention that a higher temperature was necessary.
The more we explored the topic, the more we found that what we had always believed to be true was not supported by the research. Michaels and his colleagues published data in 2001 that concluded that water temperature had no effect on the level of bacterial reduction when using nonantibacterial soap. A follow-up study published by Michaels and another group of researchers in 2002 found similar results, but also noted that the higher water temperatures resulted in skin irritation and loss of water content, a complaint that has often arisen as a frequent barrier to hand washing in the foodservice industry.
Temperature is important because we want out employees to be comfortable washing their hands, so warm water at the hand washing sink is important. But if water temperature is not important in bacterial reduction on the hands, what is? A quality soap, friction (time), and rinsing. Encourage your employees to do these steps and they can help protect your business and themselves from food handler contamination.
I must close with my usual disclaimer when talked about the updated food code – be sure to follow your local food code. Although the 2022 Model Food Code has been released, most jurisdictions are still operating on older versions of the code, and it is important to know the specific requirements in your area. Risk Nothing.
Sanitation, Sanitation, Where Art Thou?
Continuing the theme I picked up on a few months ago, discussing common causes of foodborne illness, I’d like to focus this blog on cross contamination, more precisely sanitation. Sanitation is another issue that employees don’t often do at home, so they discount the importance of it in the food production environment. That is to say that they have never made someone sick at home because they only clean their countertops and they have likely never sanitized their kitchen, so why is it so important in a foodservice facility?
Handwashing: The Habit that Isn’t as Common as We May Think
Earlier this year, I started to focus our FoodHandler Food Safety blogs on common food safety issues faced in each foodservice operation across the world. We’ve covered some of the most common issues, but perhaps none is more common than improper hand hygiene.
Is Implementing a Color-Coded Food Safety Plan Right for your Operation?
Foodborne pathogens are by far the most prevalent cause of foodborne illness in the United States and across the world. There are 31 known agents that cause foodborne illnesses, and more that are unspecified or yet undiscovered – remember, E. Coli 0157:H7 wasn’t identified until the early-1980s. It is estimated each year, 48 million illnesses occur because of these known and unknown pathogens, resulting in over 3,000 deaths.
Maintaining your Equipment: Is it the Missing Ingredient in your Recipe for Food Safety?
Although I am no longer in day-to-day operations, between our students and foodservice lab at the university and my volunteer activities in my local church, I keep a close hand in food production. This past week, I had the opportunity to lead a group of men at our church in preparation of a luncheon for 100 women who were attending a spirituality retreat. Over the course of the morning, I realized our main cooler in the kitchen was not functioning properly and was about 10˚F above the required temperature. While we do have a commercial kitchen, we do not routinely log temperatures, so when the unit started to malfunction is questionable. Even more concerning was not the lunch we were preparing for, but the dinner that was served the night before for 300+ families in the parish.
