10 Principles of Sanitary Design
Design Criteria for Process Equipment
To reduce the risk of microbiological contamination outbreaks, all product inspection equipment should be designed with due consideration to the application, operating environment and cleaning regimes likely to be encountered, and should adhere to the following 10 principles of sanitary design.
1. Cleanable to a Microbiological Level
Food equipment must be constructed to ensure effective and efficient cleaning over its lifespan. It should be designed to prevent bacterial ingress, survival, growth and reproduction on both product and non-product contact surfaces.
2. Made of Compatible Materials
Construction materials used for product inspection equipment must be completely compatible with the product, environment and cleaning/sanitizing chemicals, as well as the methods of cleaning and sanitation. Product contact surfaces should be made from materials that are corrosion-resistant, non-toxic and non-absorbent.
3. Accessible for Inspection, Maintenance, Cleaning and Sanitation
All parts of the product inspection equipment should be readily accessible for inspection, maintenance, cleaning and sanitation without the use of tools. Clean-in-place (CIP) is preferred over clean-out-of-place (COP) to avoid time-consuming disassembly and re-assembly.
4. No Product or Liquid Collection
Equipment should be self-draining to ensure that liquid, which can harbor and promote the growth of bacteria, doesn’t accumulate, pool or condense on the equipment.
5. Hollow Areas Should Be Hermetically Sealed
Hollow areas of equipment such as frames and rollers must be eliminated, wherever possible, or permanently sealed. Bolts, studs, mounting plates, brackets, junction boxes, name plates, end caps, sleeves and other items must be continuously welded to the surface of the equipment, not attached via drilled and tapped holes.
6. No Niches
Equipment parts should be free of niches such as pits, cracks, corrosion, recesses, open seams, gaps, lap seams, protruding ledges, inside threads, bolt rivets and dead ends. Welds should be flush and free of pits, cracks and corrosion.
7. Sanitary Operational Performance
During normal operations, the product inspection equipment must perform so that it doesn’t contribute to unsanitary conditions or the harborage and growth of bacteria. The characteristics of the product being produced will have the greatest impact on the equipment’s operational construction specifications.
8. Hygienic Design of Maintenance Enclosures
Maintenance enclosures and human machine interfaces (HMIs) such as push-buttons, valve handles, switches and touchscreens must be designed to ensure that product residue or water doesn’t penetrate or accumulate in and on the enclosure or interface. In addition, the physical design of the enclosures should be sloped or pitched to avoid use as a storage area or residue accumulation point.
9. Hygienic Compatibility with Other Plant Systems
Product inspection equipment should be designed to ensure hygienic compatibility with other equipment and systems, such as electrical, hydraulics, steam, air and water.
10. Validate Cleaning and Sanitizing Protocol
Procedures for cleaning and sanitation must be clearly written, designed and proven to be effective and efficient. Chemicals recommended for cleaning and sanitation must be compatible with the equipment and manufacturing environment, and capable of removing product residue as non-aggressively as possible.
The Benefits of Hygienically-designed Equipment
Although the initial upfront cost of purchasing hygienically designed equipment can be more than non-hygienic equipment, the benefits are multitudinous. As well as helping to protect consumer welfare and a company’s brand reputations by increasing food safety and reducing the risk of recalls, hygienic equipment can help with regulatory and Hazard Analysis and Critical Control Points (HACCP) compliance.
But that’s not all — investing in hygienically designed product inspection equipment can also lead to long-term cost savings and increased operational efficiency by allowing run times to be extended, shortening cleaning times, reducing cleaning chemical and water usage and lowering maintenance costs.