One of the most common causes of food safety problems is a flaw in the sanitary design of food processing equipment. When building new facilities or installing new lines, many food manufacturers struggle with increasingly fast-paced project schedules and limited funds, which affect priorities assigned to sanitary equipment design and requirements during the early stages of a project.
Food processors can save significant capital dollars if they invest the time to “engineer out the problem” when first designing a new line – rather than wait to correct issues discovered after installation.
Key sanitary design issues and areas that should be addressed during the equipment design phase include:
Nooks, cracks and crevices – at its core, sanitary equipment design is about controlling potential harborage areas where undesirable microorganisms may cultivate
Equipment feet – equipment should be designed with the minimum required number of legs to reduce harborage possibilities with special considerations for a ball foot, screw foot, welded-insert foot, plastic foot, or stainless steel foot
Off-the-shelf equipment – custom equipment design should eliminate unwanted mounting holes that may be present in off-the-shelf equipment
Welding methods – using inappropriate welding methods can impact food safety. The single V-joint method is preferred over other methods such as square-butt joint, lap joint or T-joint, as those can lead to niche areas where debris can become trapped
Drill and tap – mounting plates, brackets, junction boxes, nameplates and similar items should be attached to a stainless-steel tube or pipe utilizing continuous welded stand-offs, or be continuously welded to the surface, not attached via drilled and tapped holes
Flat surfaces – plants should minimize flat surfaces, especially in wash-down areas where microorganisms are easily transferred by water. All angles on the equipment must be curved or rounded with a quarter-inch radius or more
Equipment finishes – select the correct finish on stainless-steel material for food contact surfaces verse non-food contact surfaces to effectively clean and eliminate any chance of bacterial survival.
If you would like to learn more about steps you can take to ensure food safety during the equipment design phase, contact me at foodforthought@stellar.net.
Are you aware of the concern of use of hollow structural members (square tubing, pipe). Even if specified as for capped and continuous welded fabrication, after exposure to high pressure wash downs in a food plant environment this type of contruction harbours infestation. Many times mechanics have cut into such members to find black, smelly ooze coming out. Best practise is to not use any hollow members for equipment, platforms, handrails etc.
Hi Ronn: That’s a good point and it’s definitely something we’re familiar with. For example, we’ve used solid round stock to make frame members. Unfortunately we find for many of our clients that it’s cost prohibitive, so we implement other more cost-effective measures, such as no drilling and tapping, capping everything, making sure everything is seal welded, sleeving anything that has to be passed through, etc.