Delta Dust and Tempo Dust are both pyrethroid insecticide dusts used for crack-and-crevice pest control, but they differ in one critical way: Delta Dust is waterproof, and Tempo Dust is not. That single difference drives most of the decision between them. Both kill a similar range of insects, both come in ready-to-use dust form, and both are applied with a hand duster into voids and crevices where pests hide. The right choice depends on where you’re applying it and what you’re trying to kill.
Active Ingredients
Delta Dust contains deltamethrin, while Tempo Dust contains cyfluthrin at a 1% concentration. Both are synthetic pyrethroids, a class of insecticides modeled after natural compounds found in chrysanthemum flowers. They work the same way: contact with the dust disrupts an insect’s nervous system, causing paralysis and death. The practical difference between the two chemicals is subtle for most home pest control situations, but it shows up in how fast each product works and how long it lasts.
Moisture Resistance
This is where Delta Dust pulls ahead for many applications. It’s a completely waterproof formulation that won’t clump, cake, or absorb moisture. That means it stays effective in exactly the kinds of places insects love: damp crawl spaces, around sewer drains, near plumbing, and in humid wall voids. Most insecticide dusts lose their effectiveness when they get wet because the particles stick together and stop adhering to insects. Delta Dust avoids that problem entirely.
Tempo Dust does not have this waterproof property. It performs well in dry environments like attics, wall voids, and indoor cracks, but in any area with consistent moisture or humidity, it will degrade faster and may clump. If you’re treating a dry indoor space, this distinction matters less. If you’re dusting around pipes, in a basement, or in a crawl space with any dampness, Delta Dust is the clear choice.
Knockdown Speed and Residual Control
Tempo Dust is known for faster knockdown, particularly against flying stinging insects. It offers quick kills on wasps, hornets, and yellowjackets, with a residual effect that lasts up to 10 days. That shorter residual window means you may need to reapply more often, but the trade-off is a noticeably faster initial kill, which matters when you’re dealing with an active wasp nest or aggressive insects.
Delta Dust works more slowly on contact but provides a longer-lasting residual. In dry conditions, deltamethrin dust can remain effective for several months, making it better suited for preventive treatments or ongoing control in hard-to-reach areas you don’t want to retreat frequently. For slow-moving infestations like ants trailing through wall voids or insects harboring in crawl spaces, that extended residual is a significant advantage.
Target Pests
Both products cover a broad and overlapping list of insects. Tempo Dust is labeled for ants (including carpenter ants, fire ants, and pavement ants), bed bugs, wasps, hornets, yellowjackets, and a range of other household pests. Delta Dust covers a similarly wide spectrum. For most common pest problems, either product will work.
Where they diverge in practice: Tempo Dust tends to be favored for wasp and hornet nest treatments because of its faster knockdown. You want stinging insects incapacitated quickly, and Tempo delivers on that. Delta Dust is often preferred for bed bug treatments in wall voids, long-term ant control, and any situation where the dust needs to stay active in place for weeks or months without reapplication.
Where You Can Apply Them
Delta Dust has an unusually broad label for approved application sites. It’s cleared for use in homes, apartments, restaurants, hospitals, schools, nursing homes, food processing facilities, animal kennels, greenhouses, warehouses, sewers, and even vehicles like buses and rail cars. In food-handling areas, it can be applied as a crack-and-crevice treatment as long as exposed food is covered or removed first. Containers larger than one pound can’t be used or stored in food-handling establishments.
Both dusts are applied the same way: using a hand bulb duster or bellows duster, you puff a light, even coating into cracks, crevices, wall voids, behind outlets, under appliances, around pipe penetrations, along baseboards, and into attic or crawl space entry points. The goal is a barely visible film, not a heavy pile. Too much dust actually repels insects rather than letting them walk through it.
Neither product should be applied into HVAC ducts or air handling systems, directly onto food surfaces, or in a way that allows runoff into storm drains or waterways. Don’t apply during rain or water the treated area to the point of runoff.
Safety Considerations
Both products are low in toxicity to humans through skin contact or inhalation at normal application levels. Deltamethrin, the active ingredient in Delta Dust, can cause temporary skin sensations like tingling, itching, or numbness if it contacts bare skin. These typically resolve within 48 hours. If inhaled in significant amounts, it can cause headaches and dizziness. Eye contact causes mild irritation.
For pets, deltamethrin can cause vomiting, drooling, lack of coordination, and muscle tremors if ingested in sufficient quantities. Skin contact can trigger scratching or licking at the exposed spot. Cyfluthrin in Tempo Dust carries similar risks for pets. Both dusts should be applied in areas pets and children can’t access directly, like inside wall voids, behind electrical plates, and in sealed cracks. Once the dust is in place and not airborne, exposure risk drops significantly.
Both are odorless and non-staining, so they won’t leave visible marks or smells on treated surfaces.
Which One to Choose
Pick Delta Dust if you’re treating damp or humid areas, want the longest possible residual without reapplication, or need a product approved for a wide range of commercial and residential sites. Its waterproof formula makes it the default choice for crawl spaces, basements, plumbing voids, and outdoor crevices exposed to weather.
Pick Tempo Dust if you need fast knockdown on stinging insects, are treating a dry indoor area where moisture isn’t a factor, or are dealing with a situation where quick results matter more than long-term residual. Its 10-day residual is shorter, but that rapid initial kill is hard to beat for wasp nests and hornet control.
For general-purpose indoor pest control in a typical home, Delta Dust is the more versatile option. Its moisture resistance gives it an edge in more situations, and its longer residual means fewer reapplications. Tempo Dust earns its place in the toolkit for specific jobs where speed of kill is the priority.