The Role of Sanitary Design in Pest Management
by: Patricia Hottel, BCE
Sanitary design of a food or beverage processing plant can help to reduce the potential of contamination by reducing the number of areas where bacteria and pests can harbor. As defined by the Grocery Manufacturers Association (GMA), sanitary design is “the application of design techniques which allow the timely and effective cleaning of the entire manufacturing asset” for the purpose of improving cleanability, access for cleaning and inspection, and consistency of cleaning.
As such, sanitary design can provide the foundation for a successful pest management program, not only reducing harborage areas, but also reducing the availability of food and water for pests. “The more hostile an environment we can provide through proper design, the more successful our pest management programs will be in controlling pests, said McCloud Services Technical Director Pat Hottel. “A building which is tightly constructed will help exclude pests from entering and harboring in cracks and crevices and voids inside the facility. A building which is built to facilitate cleaning will provide sanitation crews with assistance in removing food sources for pests. Lastly, it can aid in early detection by permitting easy inspection.”
Following are some explanations of the role sanitary design plays in pest management and recommendations for particular areas.
Roof
“Roofs can sometimes be overlooked for their role in pest access,” Hottel said. But it is important to monitor and check for pest access points and attractants on the roof. Gravel roofs can be particularly problematic where processing of flour and sugar are performed, because system malfunctions can cause product spills. If these are allowed to accumulate, birds (as well as stored product pests, yellow jackets, and rodents) can be attracted to these areas. A food facility roof should be constructed so as to allow for cleaning and proper drainage.
Drains
One of the most critical areas in food plants are the drains, particularly in wet processing facilities where small flies and larger cockroaches can access the structure through the drain or breed in the organic material build up. Thus, drains need to be accessible for cleaning, and floor and channel drains must have the proper pitch for drainage. “Channel drains, in particular, can be challenging due to their size and maintenance requirements,” Hottel said.
Ceiling
False ceilings in dry processing facilities can cause cleaning challenges, thus an open, more accessible ceiling is preferred. Not only do the panel surfaces add to the amount of area to be cleaned, but they must be dismantled for cleaning access to pipes and ledges above. “If a false ceiling must be used, select panels based on removability and ability to clean,” she said. “Plastic panels will be easier to clean than a fiberboard-based tile but may be more challenging to remove.”
Walls
Because corrugated walls are very difficult to maintain and keep sealed, especially if damaged, poured concrete is preferred, Hotel said. Metal walls with laid insulation which has a plastic or metallic film cover are the worst option as they provide areas for rodents to tunnel and harbor.
Warehouse racks
“Rack legs in warehouses can be a problem and, unfortunately, I have not found a manufacturer of rack leg bases which are designed for pest prevention and cleaning,” Hottel said. However, some are better than others. When selecting a rack leg, consider how it may get cleaned, especially in areas where dry powdery products will be stored. Vacuums may be needed and sufficient electrical outlets should be planned for the proper cleaning of these areas, she said.
Air flow and proper pressure
The building should be designed so that air flow is outwardly positive. If a building is built with negative air flow or airflow becomes negative over time due to changes in the building design, flying insects can become a major issue. So, Hottel said, “If a building has a negative airflow issue, doors and paths from the exterior should be monitored and the appropriate devices used to help capture flying insects which may enter.” The use of vestibules to help isolate pests in a negative air flow situation can be another option.
