Exclusion: Most Powerful Weapon in Fight Against Rodents

From production to processing, distribution to preparation, each step of the food production chain presents a unique set of food safety challenges. One challenge, however, is universal across all facets of the food industry—pest control. Technologies may advance, supply chains shrink, and food trends evolve, but the pest control battle wages on, with rodents often leading the charge for the opposition.

Rodents eat or contaminate at least 20 percent of the world’s food each year. Their ability to contaminate on such a large scale is due in part to their “nibbling” habits, wherein they come into contact with far more than they actually consume. In addition, in just one year a rat can shed more than half a million body hairs, and a mouse can produce up to 18,000 fecal droppings. In that same year, a pair of rats can produce over 1,200 descendants. Within three years, that can grow to half a billion descendants! Rodents have been linked to asthma and transport fleas, lice, and ticks. The CDC also points out that they carry diseases including rat bite fever, hantavirus, leptospirosis, salmonellosis, murine typhus, and even the bubonic plague.

These are just a few of the disturbing statistics that highlight the importance of preventing infestations before they occur. Once rodents are inside, it is already too late. USDA Sanitation Performance Standards require that “establishments must have in place a pest management program to prevent the harborage and breeding of pests on the grounds and within establishment facilities. Pest control substances used must be safe and effective under the conditions of use and not be applied or stored in a manner that will result in the adulteration of product or the creation of insanitary conditions.”

The use of chemical rodenticides in the food industry is impractical, ineffective, and often highly dangerous. Exclusion—the method of creating physical barriers against rodents and pests to prevent them from entering a building in the first place—is preferred among industry professionals as the safest and most effective pest management strategy available. Fundamentally, it involves the elimination of cracks, crevices, and other spaces that allow rodents to gain entry. The CDC lists “sealing up holes inside and outside the home to prevent entry by rodents” as its number one suggestion in preventing rodent infestations. The New York City Department of Health and Mental Hygiene recommends “sealing all cracks, crevices, and holes in walls, cabinets, and doors” as its top guideline for controlling conditions that promote pests.

Rodent exclusion is fundamental to food safety. Keep the rodents out—plain and simple. Or is it? These tenacious pests are relentless in their pursuit of food and shelter. A mouse can squeeze through an opening the size of a dime, and a rat through an opening the size of a quarter. Rats have the ability to gnaw through plastic, wood, aluminum, brick, cement, and even lead. They can climb wires and rough surfaces, swim considerable distances and tread water for several days, making them a worthy opponent to say the least. But with a comprehensive exclusion plan and employee diligence, it is entirely possible to keep rodents at bay.

Safeguarding Your Building

Building access points are not difficult for rodents to find. The most obvious, and therefore the most critical to protect, are exterior doors. Without proper exclusion, rodents will literally walk through the door and compromise food safety. Personnel doors, garage doors, and loading dock doors are all at risk. Exterior doors should remain closed whenever possible, and sheet iron flashing should be installed at the base of wooden doors, which are susceptible to rodent gnawing.