© Seventyfour | Adobe stock

Facilities that process and package food products may be plagued by many types of pests, chief among them cockroaches. The more moisture present within a processing area, the greater the potential for cockroach infestations — in particular, German cockroaches. Older buildings tend to have more issues with American and Oriental cockroaches than newer facilities.

Controlling cockroaches in food processing is complicated by the amount and types of equipment, level of maintenance of equipment, walls, etc. (harborages); adherence to good sanitation practices (food); and how the facility is cleaned such as via water/hoses (moisture). Once German cockroaches have been introduced into an area, each of these plays a role in level of infestation that might occur.

The pest management professional (PMP) has a difficult job in trying to keep food processing areas as free of cockroaches as possible. First and foremost is access for service to find and treat any active harborages. Most facilities cannot have a PMP present during operations even to do a visual inspection due to the level of activity, type of machinery present and a variety of safety reasons. Therefore, services need to be scheduled during downtime, which limits the opportunities for more preventive inspections and treatments when needed.

Another complicating factor is the amount and type of machinery, as these will be where most German cockroaches harbor, hiding in cracks, motor housings and voids within the machinery itself. When cockroaches have been sighted in or around an area, usually a facility maintenance person is needed to gain access for the pest professional to find and treat the cockroaches.

In the absence of known activity, a PMP will use visual inspection and a non-residual pyrethrin flushing agent to look for pockets of activity. Where available, interviewing employees who work in the area as to if and where they saw pests helps to target the inspection. During downtime when pest services are done, such employees may not be present. The pest sighting log is also helpful in determining where cockroaches may be active, but it is important for the facility to be specific in its notes to assist the pest professional to the sites of activity.

Service Approach

The pest professional, upon arrival, will typically first consult his or her key contact person and the pest sighting log. If activity is reported, the PMP will inspect and service those sites first. In the absence of reported activity, the PMP will likely proceed to the next area in the service schedule in the written pest management plan.

Whether servicing active areas or checking to find any activity, the approach will be the same — visual inspection and flushing agent to expose hiding cockroaches. Hot air in the form of a heat gun or hair dryer can be used in place of a flushing agent to chase cockroaches from harborages, and this technique can be done when light operations are ongoing (i.e., not during a downtime period).

Monitoring traps are typically not useful in food processing areas because they will be contacted by water and dust. They also are usually removed during cleaning activities. Traps may be used in secure, dry locations such as within storage cabinets and motor housings, attached to storage racks or false ceilings, or in pipe chases or similar locations.

Because the application of residual insecticides is very limited for food processing environments, use of a vacuum to remove cockroaches as they are flushed provides some level of immediate control. Population reduction through vacuuming then makes it easier to control remaining cockroaches via other methods. Infested floor drains, for example, are one site where treatment is not permitted, so flushing and vacuuming such drains frequently removes all cockroaches harboring within the drain.

Residual treatments will be limited to crack, crevice and void treatments, with some label-allowed spot treatments depending on the type of food area and if this is permitted in the written pest management plan. These applications should only be made to active harborages where foods are processed or packaged (i.e., equipment). Preventive residual treatments may be applied into wall voids and pipe penetrations into walls or floors and gaps or treatment holes sealed following application. Again, follow directions on the product label(s) and detailed in the written pest management plan for the facility.

Cockroach services will proceed in a similar manner as the PMP completes service in a given area. What treatments may be done will differ for a piece of processing equipment compared to warehouse storage racks, expansion joints in floors, restrooms and offices, etc. The further away from the handling of food, especially as it is processed and exposed, the more flexibility the pest professional will have in how to monitor and treat active cockroach harborages.

No specific treatment strategy or product will be right for every situation encountered, particularly between different areas within a facility or between different types of food facilities. When difficult to control situations are encountered, discussions between the facility staff, the PMP and his or her management team will be needed to decide on an appropriate plan to remediate the problem area.

The author is owner of Stoy Pest Consulting.