Process Expo
Ramakrishnan Narasimhan presents during the PROCESS EXPO.
CHICAGO – During the second day of Process Expo, a food safety expert provided insight into protecting food processing equipment from food safety hazards and the role of sanitary design in the construction of processing and packaging machines. Among the topics covered by Ramakrishnan Narasimhan, vice president of product safety and research with Troy, Michigan-based Perry Johnson Registrars Food Safety Inc. were seven functional design requirements for food processing equipment and some parameters for monitoring and measuring the requirements. They included:

- 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.