Hygienic Design for Processing Equipment

In the more than 40 years that I have inspected processing facilities and evaluated equipment design, I have found an alarming number of equipment buyers and users that equate the mere shininess of stainless steel as hygienic. Stainless steel and other noncorrosive materials are, of course, important but the hygienic aspects of the equipment come from the details of the design. The basics of hygienic design are universal. It does not matter if you are processing dairy products, meat products, fruits, bakery products, or any other of the myriad of food products manufactured, the basics are the same. There may be differences in the details of materials or design features of construction to accommodate a specific product or process, but the overall principles won’t change. As the saying goes, “The devil is in the details.” And the devil is the potential for contamination and loss of customer trust.

There are a number of false perceptions about hygienic design and hygienic processing, such as the following.

There are levels of cleanliness. This is false. Clean is like being pregnant; you either are or you’re not. There are, however, levels of soiling that you have to consider as acceptable for your particular process. These may vary from the very slightly soiled, moderately soiled, heavily soiled, to call out the hazmat crew.

Hygienic design costs more. In the short run this is often true for some equipment. The materials of construction, often stainless steel, and the design details increase the initial, up-front cost. The long-term benefits of hygienic design over the life of the equipment will reduce the overall operating costs. Often run times can be extended, cleaning times shortened, cleaning chemical and water usage reduced, maintenance costs lowered, and a longer life of the equipment can reduce return on investment. When you purchase less expensive non-hygienically designed equipment, the old adage “You get what you pay for” applies.

Hygienic design is bad, complicated engineering. This is false. Hygienic design when applied from the very first steps of the design process is very good engineering. Hygienic features such as the removal of cracks and crevices to eliminate microbiological contamination also reduce such engineering problems as stress and crevice corrosion. Proper selection of materials of construction can reduce the potential for pitting of surfaces and galvanic interactions between dissimilar materials. Ease of disassembly for sanitation purposes is also ease of disassembly for maintenance personnel, reducing downtime.

We can modify existing designs in-house to be just as hygienic. In theory this is true. Any design can be retrofitted to eliminate the hygienic hazard issues. It’s just a matter of time and money—lots of time and lots of money. The end cost of retrofitting is routinely significantly higher than the purchase of new hygienically designed equipment.

I don’t have anyone on staff that can truly evaluate a new purchase for sanitary design. You’re in luck; the lion’s share of this has been done for you and is already available in the market place.

Standards in Place

The hygienic standards writing organization for dairy and food processing equipment is 3-A Sanitary Standards Inc. Its Standards and Accepted Practices are recognized internationally. During the 1920s, the need for more stringent and uniform standards for dairy processing equipment became evident as the U.S. economy and consumers entered the modern era. Representatives of three interest groups—processors, regulatory sanitarians, and equipment fabricators—saw the need for cooperative action and introduced the first industry standards for equipment. These standards became known as 3-A standards for the three interest groups that forged a common commitment to improving equipment design and sanitation. Unlike other types of standards, 3-A Sanitary Standards relate to the cleanability of dairy equipment.