No part of a food plant takes more punishment and abuse than its floor. Fortunately, most plant managers understand this and devote sizable dollars to its maintenance, upgrade and sanitation treatments annually.
Stonhard recommends a smooth, flat surface, but with some texture to provide secure footing even when the surface is wet or slick with matter
What some may be overlooking, however, are the advances in flooring and floor-cleaning technology that make maintenance and sanitation easier and more effective than ever before. The science of floor hygiene seems to advance every year.
Addressing the strict hygiene standards required by food regulatory agencies, including the FDA and USDA, make food plant floors a constant cause of concern. Most food plants are subjected to radical temperature fluctuation, human and machine traffic, food and chemical abuse and the punishment of heavy equipment installation and use. Dangerous pathogens find floors the best places to hide.
One important issue floor coatings manufacturers have been addressing diligently is VOCs -- volatile organic compounds. "Our Dura-Top product, sold under our Krylon industrial brand, is a 100 percent solids epoxy, and its VOC content is zero," says Sharon Sammon, product manager at the Sherwin-Williams (www.sherwin.com), coatings division, Cleveland. "It can be used anywhere in the country, no matter what restrictions are in place. More than 50 percent of our sales are going to food processing facilities."
Concrete is porous, and its pores are potential harbors for bacteria. Constant pressure from traffic, machinery and, even more significantly, heat, cold, water and water pressure can deepen and multiply those pores. "A lot of things in food are rough on surfaces, too," says Sammon. "Even the composition of food can be corrosive."
Strength and uniformity of finish are fundamental to maintaining a hygienic floor. "Our 100-percent solids 8200 Overkote HD line is a set of monolithic resin-rich coatings unique to Rust-Oleum," says Chari Droessler, product manager of industrial flooring for Rust-Oleum Industrial Brands (wwwrust-oleum.com), Vernon Hills, Ill. (The Overkote HDV line is designed for vertical applications.)
The product has twice the resin content of competitors' products and provides a stronger bond, she claims. "It's more juice than sand, more binding material," she explains. The product also offers exceptional resistance to chemicals, foods and acids common to the plant environment." It's recommended primarily for plants in which temperatures can be maintained generally above 65°F.
Urethane concrete, she says, tolerates the thermal shock of cold floors subjected to hot water cleaning more effectively. "You need flooring systems that are easy to clean and will withstand your cleaning method," adds Droessler.
She also notes plant flooring demands will vary with the segment of the industry served and even the section of the plant. She recommends specific epoxies for different conditions or resistance to different types of chemicals. For an environment where electrical equipment can be adversely impacted by static electricity - such as where robots or heavily automated equipment are in use -- she might recommend her company's ESD coating. Overkote is the preferred choice for meat and dairy plants to protect against the creation of fissures in which organic materials might build up.
Rust-Oleum also carries patch and repair products for rapid turnaround and a Sierra line with zero VOC and zero HAP (hazardous air pollutant) content. "These are ‘green,' environmentally friendly products," she says.
Although all Rust-Oleum products are designed to reduce the required preparation time, application time and production downtime, Droessler stresses proper surface preparation is critical before installing a new floor or finish.
An anti-microbial floor was a key concern when Olympia Food Industries renovated an old factory building into a food processing facility.
Andre and Kostas Papantoniou knew their company would need to invest millions if they were going to get the specialty products plant they needed for their food operation. And they did, spending nearly $20 million in an old factory building in Chicago Heights, Ill. At 60,000 sq. ft., it would soon become the world's largest pita bread manufacturing facility, making pita, flatbread and cheese-filled breadsticks.
While Olympia Food Industries would invest some $15 million in state-of-the-art equipment, roughly 25 percent of its overall investment -- more than $4.5 million -- went into upgrades and construction. But no part of that investment was as important to the project as its flooring, which proved to be a major challenge given the state of the factory. That flooring proved to be a success in more ways than one.
"We turned that old factory building into a really nice food processing facility," says Jeff Fleming, technical sales representative for Valspar Flooring, Wheeling, Ill. "They needed a floor with thermal shock resistance, but they also wanted coatability and an anti-microbial addition."
Indeed, the "anti-microbial" addition was critical -- a significant effort to invest in plant-floor hygiene. No issue in the food processing world demands such a long-term commitment as food safety. And keeping facility surfaces -- floors, walls and ceilings -- in a near-constant microbe-clear condition is an important step in making sure dangerous food pathogens never get a foothold in the plant.
Valspar along with Concare Inc., a concrete floor repair and restoration company in Melrose Park, Ill., took on the installation. One of the most difficult aspects of the project was putting in a flooring system so strong it could resist the extreme heat of baking ovens, heavy humidity, the boiling hot water of steam cleaners, freezers dropping temperatures to lower than -10°F and a spiral freezer kept at -40°F.
"Because it has the same coefficient of expansion as concrete, Flowfresh withstands extreme thermal shocks," he says, noting the surface will neither crack nor delaminate from the concrete even with repeated exposure to radical temperature fluctuations from near-boiling water to frozen storage conditions.
Valspar's Flowfresh is a urethane concrete overlay that contains Polygiene, a silver ion-based antimicrobial material that fights staph, salmonella, listeria and other harmful microbes that pose constant challenges to food safety.
Conventional epoxy flooring alone would not provide adequate protection in the mixing, proofing, preparation and cooking areas, where compliance to USDA sanitation standards is enforced. Microbial contaminants such as fungi and mildew eat at concrete surfaces, creating pockets where they can hide and proliferate. The install team applied Valspar Federal Formula clear hardener on the concrete in the silo room and two freezers. The two vendors recommended a Valspar EpoRok resurfacer for the packaging area and loading docks where the floors had been badly damaged. A simple, self-leveling 1/8-inch slurry epoxy coating was deemed adequate in non-production areas.
But the critical component for floor hygiene in the food production areas was Flowfresh RT. The Flowfresh hygienic polyurethane concrete flooring system was developed to maximize cleanliness while resisting the punishing mix of forces in a food processing environment, including heavy equipment and product loads, water damage and extreme thermal swings.
"Flowfresh is a urethane concrete overlay designed to take thermal shock from very cool to very warm temperatures and have excellent resistance to both food grade chemicals and cleaning chemicals," explains Byron Beamer, national account manager for Valspar.
It contains Polygiene, a silver ion-based antimicrobial material that fights staph, salmonella, listeria and other harmful microbes that pose constant challenges to food safety. Polygiene was developed as part of the Flowcrete group in Sandbach, England, with which Valspar has a strategic alliance.
"The silver ion technology is inert, so there are no chemicals involved," says Beamer. "As bacteria come into contact with the silver ions, they are killed." The product binds directly to the concrete and requires no primer. It can be put over green concrete as fresh as seven days.
Ancestors to this technology date back to ancient Rome. Silver-based ship coatings helped resist the growth of marine algae and barnacles. Today anti-fouling sprays are popular in the U.S. Navy, according to Beamer, to impede plant or animal life from attaching to ship hulls. The modern-day predecessor technology originated prior to World War II in chemical hazmat areas.
Today silver ion coatings are coming into their own in the food plant environment where they have proven effective on conveyor lines and equipment including meat grinders, chicken processing equipment and a variety of kill-room applications.
"The silver ion technology is a next-generation development," says Beamer. "The Flowcrete folks found a way to put it into a floor coat topping. It's good for virtually any food plant from a hog processing facility to a beverage plant, even in a brewery or a winery."
The antimicrobial technology also is safe. "That it works and works safely is a huge reason why some processors choose it," adds Fleming, noting it sets up quickly and contains no VOCs. "And, compared to like products, it is also easier to use."
Perhaps the biggest advantage of the technology is its endurance. The coating continues undiminished and uninterrupted in its resistance to mildew, mold, bacteria and fungi. The antimicrobial is spread almost evenly across the thickness of the floor coat. Traffic and wear actually activate more of the antimicrobial, which not only kills contaminants but digests the residue of the victims. The seamless coating it provides eliminates pores where bacteria can hide.
Indeed, the flooring has been incorporated into the plants of many leading food companies including General Mills, Kraft, Coca-Cola and ConAgra, according to Beamer.
Valspar also offers a wall system called Descoglas RF that reduces the traditional five-layer wall coating process to a simple two- to three-step approach. The reinforced film (the "RF" component) can be sprayed or rolled onto cinder block.
"From our perspective a lot of the talk about antimicrobials is just sizzle," counters Mike Jewell, vice president of marketing for Stonhard (www.stonhard.com), Maple Shade, N.J. "When you look at GMPs and HACCP practices, it comes down to one basic fact: When something falls on the floor, you have to clean it up."
Much of Stonhard's business comes from the food processing industry, which uses its Stonclad flooring systems -- particularly Stonclad UT, a urethane-based formulation with textured surface. The floor system, with its dense, impervious surface, resists the kinds of food acids and chemicals commonly found in the processing environment.
Note to Quality Assurance
Faulty flooring is a major risk to food safety at your plants. Work regularly with your sanitation teams to see that plant sanitation practices maximize protection. Let your team discipline include proactive plant inspection. Investigate your plant surfaces together, discussing potentially hazardous areas and looking for signs of wear, poor design and areas that may harbor bacteria.
Jewell boils down the requirements of a food plant floor to the basics. "The floor must be safe for workers and easy to clean. And it must be able to withstand the rigors of a processing facility," he says. "Plants are using CIP systems and chemicals regularly. The floors have to withstand all the exposure to food, chemicals and hot water that a processing plant uses. It requires a solid, structurally sound system."
Though Stonhard provides antimicrobial coatings due to customer request, Jewell questions exaggerated claims of their effectiveness. "There's no science that says they have a real impact," he says. Easy cleanability is the important factor, he emphasizes. "A dense polymer floor system that is pinhole free will not support bacteria," he says. "You need organic matter for bacteria to proliferate. If you drop meat on the floor and you don't clean it properly, you will get bacteria. That's why a surface that is easy to clean is the most important factor in choosing a floor."
Acid brick and quarry tile were the norm in plants for 50 years, but the vulnerability of such floors with their inherent seams and joints is clear today. For modern plants, Jewell recommends a smooth, flat surface, but with some texture to provide secure footing even when the surface is wet or slick with matter. "Polyurethane works well because it has good resistance to organic acids. When food breaks down, it can be aggressive to the garden variety of epoxy. Urethane gives the best resistance, and ours are very dense."
Pests are a constant challenge to plant hygiene, and any plan to keep plant floors hygienic should incorporate pest protective measures.
"If you have an active drain, there are some good bacteria-based products available," says Ron Harrison, director of training for Atlanta-based Orkin Commercial Services (www.orkincommercial.com). "They are cousins to those used in oil spills. If there's grease, the bacteria will chew it away so pests won't have a feeding source."
One product in that category is OE 30, Orkin's Environmental 30-Day, an environmentally friendly product that eats away grease and grime. It is a unique product to the pest-control experts specifically because it does not contain pesticides, but relies instead on naturally occurring enzymes and bacteria. "But it does require water to be effective," Harrison adds.
Harrison sees great promise in two other non-pesticide technologies: insect growth regulators, which put surplus insect growth hormones into the bug environment, and pheromones that disrupt insect mating. Last year, BASF (www.agro.basf.com), based in Research Triangle Park, N. C., introduced Phantom Termiticide-Insecticide for Ant & Roach Control, which is suitable for food handling facilities. It is a water-based formulation that lasts long and operates effectively at low chemical concentration. Moreover, the company claims it is almost odorless and leaves little residue.
BASF credits "cutting-edge chemistry" for this breakthrough product, claiming insects can't detect its active ingredient, chlorfenapyr, by taste or smell. After the pests ingest it, they cannot create energy. Eventually they become paralyzed and die.
The product's potency permits low-dose applications in specific areas where pests congregate. It can also be used in conjunction with other pest control methods.