QUESTION:

We are heat-treating a home that's on a concrete slab, and our concern is the baseboard and carpet edge. We can get everything in the unit up to temp except the floor. We thought we would treat the baseboard and carpet edge with a wet chemical before we heat treat. Should we use a knockdown like Exciter or Phantom mixed with gentrol? After we heat treat the unit for 4 hrs we want to dust the baseboard and outlets with Drione dust. Your insight on this would be greatly appreciated.

ANSWER:

Although you don't actually mention it I assume you are treating for bed bugs, and this has been an expressed concern with the use of heat - can you get the temperature high enough in all areas of the structure to kill the bed bugs? Not only spaces next to the slab may stay cool enough for the bugs to survive, but they also may find cool places within wall voids or the crawl space, if there is one. In this case there appears only to be a slab. Because bed bugs can run so quickly, the moment things begin to get uncomfortable for them they will move to seek a better location, and if the wall voids do manage to remain cool they could survive. Are you tenting the entire structure? This would help eliminate that concern.

I finally read a good article from a trade magazine (2009) on the use of dusts for bed bugs, and the authors achieved surprisingly good results with 2 of the dust products they used - Tempo Dust and Drione Dust. They got 100% kill of the bed bugs in these tests within 24 (Tempo) and 72 (Drione) hours, and suggested that the use of dusts in voids and other appropriate locations was probably an excellent option. DeltaDust also was excellent, but required much longer to kill resistant strains of the bugs. One of those locations would be along edges of carpets and behind baseboards, as well as within wall voids or voids within furniture.

So, perhaps rather than spray a liquid solution in all those locations prior to your heat treatment, and then repeat the process with a dust application, the dust could be used effectively as the first application. There should be nothing wrong with doing it as you suggest, but if the dust alone can give you 100% kill then treating it first with liquid might be duplicating your effort. Dusts last much longer than liquid applications, and the Drione in particular will last for many, many months, as well as offering insignificant toxic concern to occupants of this home. You may achieve a faster kill using the liquids first, particularly if you do add that chaser of pyrethrum, and perhaps this will ensure that fewer live bed bugs have the opportunity to move away from this area when life begins to get uncomfortable for them. Ultimately your results could be the same whether you apply both applications or only dust as the initial one.

One thought on dusting is important, and that is that dusts can easily be over-used. One consultant to our industry many years ago stated that if you can see the dust on the surface after you've applied it, it was too much dust. All that is needed is a very, very light layer on the surface to be effective, and the study I read did mention how "barely visible" deposits of the dust were still sufficient to kill the insects as they crawled over the treated surface and got the dust on their underside. This helps you to recognize that heavy dusting is not needed, and this reduces the chances of creating a visible mess in the home.