ILTs in Food Facilities

Editor’s Note: This article was adapted from Pinto & Associates.

Insect light traps (ILTs) come in many types, shapes and sizes. In a food facility like a restaurant, grocery store or food warehouse, your problem is to decide which models to install and where to put them for best effect.

Choosing Trap Type.

Whether you call them ILTs or EFKs (electric fly killers), they all use ultraviolet (black light) to attract flies and other nuisance flying insects. They differ, however, in how the insects are trapped or killed. There are two main types.

Sticky board traps trap insects on a sticky surface. Some use an electronic pulse to stun the insect, causing it to fall onto the sticky board. Others are passive traps where the insect happens to land on the glueboard. The main advantage to these traps is that insects are held whole on the sticky board with no scattered fragments that may contaminate surfaces. They are usually the preferred trap in food areas although they should not be installed above food surfaces. A disadvantage is the limited capacity of the sticky board, requiring more frequent servicing. This is most suitable for accounts with lower pest levels.

Electrocuting traps produce a high-voltage, low-amperage arc to electrocute insects that fly through the grids to the light and then hold them in a catch tray. These traps are most suitable for accounts with higher pest levels since they need less frequent servicing.

Where to Place ILTs.

The first principle of light trap placement is to intercept flying insects before they enter critical areas of the facility. If they have already invaded the facility, you want to place traps to draw them away from food and customer areas and towards the traps (see graphic above). A careful inspection is needed to determine where flies and other flying insects are entering the account and where they are resting once inside. Study the flow of people and products through the facility; flying insects follow these same pathways.

Narrow hallways are a good installation site. In general, ILTs to capture flies are placed low, only a few feet from the ground. This is where flies are most active during the day. Traps placed low are also less likely to scatter fly parts and (as a bonus), traps placed low are easier to service. The exception is ILTs used to intercept moths and night-flying insects. These should be placed high where moths fly. Place traps where there is little competition from sunlight or ambient light, but where there is low air movement. Don’t place ILTs in direct sight from doors or windows.

The authors are well-known industry consultants and co-owners of Pinto & Associates.