Pest Free by Design
Planning ahead when building new plants, additions or even when maintaining existing structures will pay great dividends.
Greg Baumann, Technical Director, National Pest Management Association
There are many pressures in any food manufacturing environment, from labor issues to gross margins and profitability. Pest management is often the last thing anyone in engineering or operations can afford to devote their undivided attention. But pest management gets undivided attention when there is a pest infestation within the plant. By taking steps during construction or maintenance, pest pressures can be minimized and, in some cases, eliminated.
Pest management can be integrated into the Hazard Analysis and Critical Control Points program (HACCP), which is the cornerstone of most quality assurance programs. New programs such as Six Sigma also integrate pest management in the quest for excellence. Further, many plants contract with the American Institute of Baking (AIB) to inspect their plants. The AIB uses their Consolidated Standards for pest management requirements.
Successful pest management programs incorporate Integrated Pest Management (IPM) with assistance from an experienced pest control professional. IPM focuses on removal of the three things pests need to survive-food, water and shelter. Food and beverage industry facilities, by design, are ripe with these sources. While some of the steps may seem to be common sense, their effect on a plant's environment (and a company's reputation) is dramatic.
The first line of defense on any plant site is to start with the outer perimeter. Look around at your location to determine if you need to step up inspections outside. If your plant is located in a suburb, the pest pressures might not be as serious as if you were surrounded by abandoned buildings and restaurants.
Set up a defensive line along the perimeter by cutting down weeds to prevent rodent harborage and make sure that there is no standing water on soil and in parking/loading. Retention ponds should aerated or circulated to keep mosquitoes at bay. Even though we don't think of mosquitoes as food pests, insects in food are a violation of the Good Manufacturing Practices regardless of where they came from.
Dumpsters and shipping and receiving areas should be free from spilled debris. If materials are loaded and unloaded outside, cleanup stations and drains should be in place. These steps will help reduce the number of foraging yellow jackets, which not only can enter the building, but can also sting workers. Shipping and receiving dock doors should be close-fitting and closed when not in use. Guards placed above the trailer bumpers will prevent mice, which can jump to door height, from entering through dock doors. If rail cars go into sheds for unloading, shed doors must fit tightly. Special inexpensive rubberized plugs are available for installing on railroad tracks at shed doors so that rodents cannot follow the tracks under the shed doors.
Lighting on the exterior should be placed away from the building and shined onto the building to avoid attracting night fliers. Also, sodium vapor lamps will attract up to 90% fewer insects than mercury vapor lamps. Zoning regulations may restrict the ability to install remote lighting. If lighting must be installed near entrances, self-closing doors should be used.
The structural members of the interior are an area where engineers can reduce pest harborages. Consider cleanability of the surfaces and components before selecting the construction material. Buss panels and controls for electrical motors are commonly held in place using angle iron and all-thread rods. Turning the angle iron so that it forms a "7" rather than an "L" will reduce food dust buildup. Food dust is a common source of stored product pest infestation.
Control panels, automation boxes, lockers, and any other surfaces which can collect dust or food debris that could lead to infestation should have tops that angle at 45 degrees so that debris falls from the top. It is striking how many infestations are traced to the tops of machinery, storage, equipment, and electrical panels that nobody ever reaches to inspect or clean. Also, these panels should be up off of the floor on stands for easy cleaning, or totally sealed to the floor. Gauges, motors, and gearboxes should be sealed to keep pests out. Conveyor belt pulleys should be covered so that no food product falls on these areas.
Flying insect control in food plants is commonly done using insect light traps (ILTs). Most target pests are houseflies and similar pests that rarely fly above five feet. Oddly, in food plants ILTs are installed on the ceilings, so access to these traps requires a massive ladder. At that height, not only is the ILT ineffective, but any flies trapped will become food for certain stored product pests such as drugstore beetles and warehouse beetles. ILTs need to be accessible and should not be installed in areas that may attract flies from the exterior, such as next to a glass entry door.
Rework areas and return areas should be separated from processing areas. The "morgue," as many plants call returned items, should be physically separated by a wall with doors, either plastic strips or solid, so that infested returned goods do not infest the plant.
Steel columns should be filled at the bottom with flooring material and angled up so that no food debris can catch in the area. Floor/wall jointures should be covered and sealed to prevent harborage. Any corrugated wall systems should be sealed at the base so that insects and rodents cannot move freely from the voids to the plant. Sealing can be time consuming, but it is a productive move, as it will greatly reduce chances of infestation.
Paint a white or yellow inspection band from the wall to eighteen inches out along all walls throughout the entire plant. This will give a good color contrast to see any pest evidence along walls. In addition, the inspection band should act as a no-storage zone.
Finally, all exterior doors should be alarmed except main employee entrances. Too many times, a late night visit to the plant will reveal that doors are propped open so employees can enjoy fresh air or as access for a quick break. Unfortunately, at night many insects and rodents are active and even with all of the best engineering, an open plant door is an open door to infestation.
When Prevention Isn't Enough
Proper prevention and exclusion methods may not be enough to deter the most evasive of pests. A qualified pest control professional can provide valuable guidance on eliminating pest populations.
The pest control industry's continued commitment to research and development has spawned a new generation of products that are low dose, highly effective and EPA-approved for use in food processing establishments. Discuss with a pest control professional the application methods that are the most appropriate for the specific condition. Granules, sprays, baits, gels, traps, or a combination provide a variety of control methods to suit even the most complex pest problem. Customers can work with pest management suppliers to design the best program for the facility.
Quality assurance professionals should select a licensed and insured professional pest control company. An experienced pest control professional who specializes in commercial accounts can assist with interior and exterior inspections for signs of pest infestations, spotting everything from conducive conditions to signs of stored product pests. Detailed records of all pest activity and control methods should be kept, and the professional pest control company should provide detailed service reports, recommendations for control, and when requested, labels and Material Safety Data Sheets (MSDS) for any pesticide used within the facility.
As with any business relationship, the key to a successful partnership with a pest control professional is communication. A clear understanding of priorities will put you one step closer to running a facility that is free from pests.