thermal fogger residual chemicals


I’ve read that some residual insecticides (resmethrin, malathion, permethrin) if applied via a thermal fogger will become a quick knock-down, not a residual treatment.   Do you have any thoughts on this ?

Thank You

Most of the common residual products like BIFEN and PERMETHRIN can be used in either water or an oil based spray. When using a THERMAL FOGGER, you must mix your product choice with some kind of DEODORIZED OIL which no doubt can affect the length of residual the chosen product might provide. Additionally, one of the main variables that can affect the length of time any product can last once applied is heat itself. With thermal foggers the product being applied is no doubt being heated up and this process alone can shorten the length of time the application remains active. Add onto this the impact of the oil base being used as the carrier for the active and it’s highly likely that in the end, the use of a thermal fogger will prove to adversely affect the length of time the product you’re applying will last. Oil contains solvents which tend to ‘break down” actives. For most applications this means a shortened life expectancy.

On the flip side of these shortcomings, there are some reasons why a thermal fogger can be the better option. If you’re dealing with a pest which is mostly always airborne and one that rarely “lands”, there is no need for a residual to be left behind when treating. A good example would be the METERED FLY MACHINES which use actives like METERED AEROSOL. These release a quick 1 second blast of product which is only active for a short time period and usually in a very small area. Even though they don’t provide residual they are quite effective when installed correctly. Thermal foggers can also cover a much larger area than traditional “wet” applications so in theory you can treat a larger area with less chemical and in far less time. Yet if you review our MOSQUITO CONTROL ARTICLE, you’ll note we don’t feel the use of a thermal fogger is really needed for the average person treating the average yard.

So in summary, we are of the belief that the use of a thermal fogger can reduce the length of time any residual active ingredient might last when compared to the same active being applied with a water base. But will this really matter? That’s the key question to ask here and the answer to this question will require a lot more answers far beyond the scope of this post. Give us a call toll free at 1-800-877-7290 for more information on any of the subject matter cited above and for your convenience, here are direct links to the products and information mentioned above:

Here are direct links to the information and products listed above:



Thermal Fogger:

Deodorized Oil:

Metered Fly Machines:

Metered Aerosol:

Mosquito Control Article:

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