- Equipment must be easily cleanable.
- Equipment design should prevent egresses for microorganisms.
- Designs should prevent the growth of microorganisms.
- Equipment should be designed to be compatible with other processing requirements and food safety programs.
- Equipment should be designed to facilitate validation of its hygienic design.
Narasimhan’s presentation was based on the negative impact inadequate equipment design has had in recent food product recalls and its role as the culprit in these incidents. He pointed out the increased focus on understanding the importance of designing, fabricating, and constructing food processing and handling equipment according to sound sanitary design principles.
Narasimhan discussed how factors such as the smoothness of equipment surfaces play a significant role in hygienic designs. Surface roughness is measured using an Ra rating. He said an Ra level of less than 0.8 is acceptable, adding that stainless steel typically has an Ra range of about 0.4. Other design elements to consider during equipment manufacturing mentioned by Narasimhan included installation that facilitates cleaning and inspection; ensuring equipment is self-draining and self-emptying; avoiding joints that overlap; properly welded joints; and ensuring supports for equipment that are void of gaps and sealed completely.