Winning the War Against Pests
November 1, 2004
Winning the War Against Pests
Along with the drive to eradicate pathogens, pest control is perhaps the meat and poultry industries’ most important food-safety endeavor.
Preventing such varmints as rats, mice, insects, and birds from infiltrating plants and contaminating food and workspaces is a never-ending battle. But the good news is that more operators are gaining the upper hand by incorporating sophisticated pest-control techniques and technologies.
“Plant managers are becoming more knowledgeable about what they can do to control pests,” says Zia Siddiqi, director, quality assurance, for Atlanta, GA-based Orkin Commercial Services, a provider of pest control products and services. “No company wants to appear on the news because a consumer got something extra in his or her product that was not on the label.”
Insects and rodents typically are attracted to the odors emanating from facilities, and the degree of plant cleanliness frequently is the difference between creating an environment in which the pests either starve or thrive, he notes.
Cockroaches, which often enter facilities via shipping boxes, are among the most persistent threats. Roaches hide in cracks and crevices, and they gravitate to wet and moist areas. Laying poisonous bait near areas harboring the insects is one of the main ways to eliminate such pests without spraying insecticides, Siddiqi says.
Treating sites with non-toxic flushing agents prior to deploying bait will indicate to operators the extent of the roach population and how much action is needed. Bait often is administered in 2-inch long beads when a plant is shut for cleaning.
“You can bring a cockroach home, but if you keep the home clean and starve the insect it is eventually going to die,” Siddiqi notes. “That is the approach that should be taken when designing pest-management programs.”
Keeping flies from entering plants also is accomplished through strong sanitation methods and by incorporating such technologies as air curtains and ultra-violet lights. An air curtain features high-speed fans that will blow air in a downward angle towards an entry door within a facility. The force of the air pushes flies away. Maintaining positive pressure does the same trick, which causes air to flow out of buildings when doors are opened.
Ultra-violet (UV) lights are effective in luring insects to their death. Some UV-based systems will electrocute or stun flies that venture too close to the lights, or snag the insects on boards coated with sticky materials. Such apparatus typically is most effective when placed near plant doors.
Maintaining a clean facility, however, is perhaps the best way to minimize fly infiltrations, Siddiqui says.
“There is little need for chemical applications to handle the insects because ninety-five percent of fly control is sanitation,” he notes. “Because they are attracted by smell, the quality of a cleaning program and frequency that a plant is hosed down are most important.”
To draw flies away from buildings, outdoor lights should be situated on poles located at least 30 feet—and preferably 100 to 200 feet—from the plant, and be pointed toward the facility.
“Lights that are mounted over doorways will attract insects, and that increases the odds that they will get into plants,” says Don Graham, president of Chesterfield, MO-based Graham Sanitary Consulting Ltd.
Insect control, however, often is less of a burden within the plant spaces that operate at lower temperatures. “It can be forty-degrees F or less in process areas and insects can’t thrive in such cold,” he says. “But rodents can.”
Indeed, rats and mice typically are more potent foes for building operators. But they also can be contained by incorporating intricate plant designs and the strategic use of bait, traps. and other tools, analysts say.
To help prevent rodents from burrowing into plants, for instance, operators can dig a 30-inch wide and 4-inch deep trench around the perimeter of facilities, Graham notes. Filling the trough with pea gravel makes it virtually impossible for rats and mice to maneuver through the ditch, he adds.
Installing a flat cement shelf 24-inches below ground level when foundations are laid for new buildings also provides a solid barrier to entry. But the first line of defense at a plant typically is the placement of mechanical traps and bait stations on the outskirts of a facility.
Bait stations usually are constructed of plastic with holes on the sides.
Rodents entering the stations often die shortly after ingesting its cereal-based poison.
Plant personnel can more easily detect evidence of rodents, such as holes and fecal material, when shrubs and other landscaping are situated away from buildings.
Other mechanisms designed to deter rodents include the brush seals that are situated at the bottom of doors and other points of entry. The brushes prevent rats and mice from entering facilities through tiny spaces, and are particular effective in shielding the pit under the leveler plate in the loading dock, Graham says.
The leveler plate is a platform that rises from the warehouse floor and enables workers to drive forklifts onto the back of trucks. Installing a brush around the edge of the leveler plate keeps rodents from jumping into a closed pit and then accessing a plant through the warehouse floor.
All pipes and other openings should be no larger than one-quarter of an inch to keep mice from entering, and less than one-half inch to repel rats, Graham says. And ledges that enable rodents to maneuver within buildings should be removed, Siddiqi adds.
The plant roof, which often functions as a repository for food particles and bird droppings, both of which attract rodents and insects, also can be “pesterized.” Instead of covering facilities with stone ballast, which can trap crumbs and contaminants, operators should top their structures with singe-membrane rubberized roofing that glues to the surface and is easy to clean, Graham says.
“Many pests are carriers of bacteria, and birds are notorious for having salmonella in their droppings,” notes Terry McAninch, a research and development specialist at Birko Corp, a Henderson, CO-based manufacturer of sanitizers and disinfectants for the meat industry — and a distributor of insecticides.
Indeed, birds can be especially difficult to combat because they are able to nest in a multitude of locations on the exterior of buildings, including the canopies above doors. Many operators install spikes along the edges of walls as a deterrent, and another effective practice is to minimize the use of flat areas when designing or renovating plants, Graham says.
“Birds can be as dirty as rodents, and if doors stay open for any length of time they will get into buildings and perch on ceiling rafters,” he notes. “Bird droppings—which also can contain e-coli and other organisms—and dirty feathers also can easily contaminate work areas.”
But because many birds are protected by federal regulations, plant operators should focus on insulating their buildings without causing harm, he adds. Traditional methods include installing screens over all windows and insuring there are no spaces in walls large enough for birds to enter.
Choose your poison
Insecticides and poisons, however, typically can be earmarked for all insects and rodents, and a wide selection is available. A common agent is pyrethrum. Because it dissipates rapidly after use, it is acceptable for food-contact surfaces, McAninch says.
It is important, however, for plant operators to routinely rotate among a variety of poisons to prevent pests from developing a tolerance to specific agents, he notes.
“It is helpful to shock the system periodically to get rid of those pests that develop resistance to certain chemicals,” he adds. “The strategy should be to deal with the pests before they move inside the plant, but operators need to know how to maintain control in all locations.”
Among the processors giving an added focus to pest prevention is Smithfield Foods Inc., Smithfield, VA. Joe Weber, Smithfield vice president of fresh pork, say his organization is continually reengineering its facilities to incorporate newer features that deter rodents and insects.
“Pest control is an important part of food safety and is at the top of the radar screen,” he notes. “The topic doesn’t grab the headlines like it did twenty years ago, but upgrades in designs have made the plants much better able to control pests than ever before.”
While many processors create and execute their own pest-control measures, Graham says it often is more prudent for the companies to employ outside experts in order to leverage the most effective solutions.
“By using a third party, the processor’s food-safety activities also can appear much more credible in the eyes of the regulatory authorities,” he notes. “Depending on the extent of a problem, the exterminators can make either weekly, bi-monthly, or monthly visits and inspections.”
But whether treatments are handled internally or by outside professionals, it is crucial that all procedures are documented —and that a record also is kept of the dates that specific pests appear. Such information will enable processors to be better prepared to deal with future incursions.
“Plant quality-assurance and sanitation managers can play a big role in pest control,” Siddiqi adds. “Oftentimes processors will hire outside operators who they think have the magic bullet, but a lot of the results also will come from their own practices.” np
Technology suppliers participating in this article include:
Orkin Commercial Services, phone (404) 888-2780 or (800) ORKIN-NOW, fax (404)888-2012, e-mail email@example.com, or visit www.orkin.com
Birko Corp., phone (800) 525-0476 or (303) 289-1090, fax (303) 289-1190, e-mail firstname.lastname@example.org, or visit www.birkocorp.com
Richard Mitchell is a freelance writer based in the Chicagoland area
Richard Mitchell is a freelance writer based in the Chicagoland area
Pest Control Tips
Insects and rodents typically are attracted to the odors emanating from packing and processing plants. The degree of plant cleanliness frequently determines the difference between creating an environment in which pests either starve or thrive.
Keeping flies from entering plants is accomplished through strong sanitation methods and by incorporating such technologies as air curtains and ultra-violet lights.
To draw flies away form buildings, outdoor lights should be situated on poles located at least 30 feet — and preferably 100 to 200 feet — from the plant and pointing toward the facility.
Plants should have a 30-inch wide by 4-inch deep trench around the perimeter of facilities filled with pea gravel, which makes it impossible for rats or mice to maneuver through the trench.
Installing a flat cement shelf 24 inches below ground level when foundations are laid for new buildings provides a solid barrier to prevent rat and mice entry.
All pipes and other openings should be no larger than one-quarter of an inch to prevent mice from entering them.
Plant operators should routinely rotate a variety of poisons to prevent pests from developing a tolerance to specific agents.