We have a fleas problem at home. We started to apply diatomaceous earth powder and boric acid to our carpet area since beginning of September and right now the problem seems to be under control (we rarely get stung by fleas now. Diatomaceous earth works great in killing fleas. I found death fleas from both the carpet area and tiles area where we left diatomaceous earth. Because of the mechanical nature of the killing action, there are only a certain number of fleas that it can kill in a day; if the fleas infestation is so bad that more adult fleas pop up than what DE in our home can kill daily, our fleas problem will get worse instead of getting better. DE (and boric acid as well) should be used to contain small to medium size fleas infestation. In a truly massive outbreak, daily vacuuming to remove as many fleas, larvae, and eggs as possible is going to be more helpful than DE until the fleas population is under control. Since we have a dust separator and it deposit the dust into a bucket, I verified that DE kill fleas of all size in both tiles and carpet area. I was mighty please that I found 7 dead fleas when I vacuum out the DE in the Master bathroom (a room that I thought was clear of fleas. How wrong can I get?) The best recommendation for DE usage I read involve 1) apply DE on carpet and then vacuum out DE from the carpet 12 to 48 hours after the initial application (for tiles surface, just spread DE on it and vacuum it out with the same schedule as carpet area). 2) Then vacuum the house daily 3) Apply DE again 7 days after the initial application. Repeat the cycle 4-5 times. In our case, since we don’t see adult fleas much (but still a lot baby fleas), we modify the plan and left DE in the carpet (boric acid was vacuumed out a few days after application) until an area with active baby fleas population (my feet will tell me where the active baby fleas are). If I feel active baby fleas in the carpet, I would vacuum out the DE and go through vacuum twice a day routine on the infested area for 2-3 days and then apply the DE again. My hope is that the vacuuming will control the infestation to the point that DE in my carpet can kill the new fleas fast enough. And we will left the DE in the carpet for the next 6-9 months at least. So far the plan seems to work well (we are in day 17 now), I only vacuum selected part of the house every day and the fleas is still under control. Maintaining a thin layer of DE on tile surface is not an easy task. In a busy room like the kitchen where a lot of people walking in and out, DE tends to get pushed to the grout line and stay there. By the end of the day, we are back to smooth tiles surface with most if not all the DE are in the grout line. Our solution is to swipe up all the DE with broom and pan and re-apply DE at night. The average time it take DE to kill a fleas is between 4-6 hours. So for the ‘DE on tile surface’ plan to work, we need to find a window of 8-10 hours that the kitchen is off limit to everyone after we reapply the DE daily. For the garage area, we wash the floor with 5:1 diluted bleach solution weekly since DE in the garage is a no go. I am concern that the filter in my car will get destroyed if it suck up some DE on the garage floor We also bought some Victor fleas trap(M230A, 8 of them) and deployed the traps to each room . We started with 3 and like it so much that we get the rest and put them to use in different parts of our house. And it is very helpful to have the fleas trap as our last line of defense. We caught a few fleas in rooms that we thought is clear with the DE. The operating cost of these trap are very low (about 10 cents a day including the cost of burned light bulb and electricity). For easing our mind, these fleas trap is a great investment. Steam cleaner (the one with steam over 220 F) can be helpful to kill fleas in small area or furnitures. I used to have a McCullogh MC1375 for a while and in the process of switching to a Dupray neat steam (advertised to deliver 275F steam). It will be very useful to clear the stubborn small fleas infested carpet area, chair, sofa, bed with steam cleaner. Much faster than DE or salt/baking soda but more labor intensive so steam cleaning only work for small area. Since fleas operates 24x7 in reproducing and biting us, we can never hope to out work them. The best hope, I think, is to make our home so hostile to the entire cycle of the fleas life to get rid of them. Boric acid, DE, and heated fleas trap all work 24x7. And hopefully we can defect these pest with these tools over time. After the past 17 days, our tiles area are reasonably clear of fleas activities (DE is on the tile throughout). Some carpet area still have baby fleas activities and I am vacuuming those area daily. Garage seem to be clear of fleas at this point. Cars still need work. DE is very messy to handle and easily blow out my home vacuum cleaner. we use a shop vac to vacuum out the DE when needed (Rigid 6.5 HP sold in Homedepot) and a dust separator (also sold in HD). Once I vacuum out the DE and boric acid from the carpet, I start to use my Dyson V11 for the daily vacuuming. And the filter in dyson V11 has to be cleaned using the blowing function of the Rigid shop vac 7-8 times already (the shop vac pick up most of the DE. DE buried deep in the carpet will cause problem for our V11) and 3 new V11 filter in the last 17 days. I can’t imagine a way to handle DE without a shop vac and constantly cleaning filter. PS: update this review on 9/27/20 (about 3 weeks after initial application of DE). We still have a couple areas in our home (a small carpet area in dinning room and a small carpet area in family room) that still have some fleas activities. DE kill fleas slowly (take average 4-6 hours ) and it seem to be more effective in killing larger flea than small one. That mean I notice some stinking bite from the small male fleas occasionally from those small infested area). For now I just try to avoid these area and wait until the DE kill the small male fleas. Since we applied DE and boric acid in our house starting 9/3/20, we saw progressively less fleas activities in our house, I am hopeful that we will ultimately clear these 2 small area and our car of fleas . I cleaned the filter in the shop vac for the first time a couple days ago, and it is ugly. DE and boric acid stuck in the filter and I have to wash the shop vac filter. Be prepare to do a lot of filter cleaning on both your regular vacuum and shop vac when you use DE. One thing I really like about DE is that we have not sprayed any insecticide in our home since 9/3 and still have the fleas under control (not eliminated yet). Victor fleas trap is my last defense in car DE fail to kill some fleas.. I am hopeful that we can eliminate fleas in another 4-6 weeks. PPS: update 10/4/20. As it turns out DE is very good in killing the female fleas which is bigger in size but it is much slower in killing the Smaller male fleas. we had 4 small area in our house and my car ( around 3x5 ft or so on an average) still have fleas. I noticed that I will get bitten once in a while if I stay in these in these small infested area. Obviously the most important one to kill are the female fleas since it break the cycle of more fleas. But these small male fleas can live a lot longer than the 4 to 6 hours average. So I vacuumed out the DE and applied 50/50 very fine salt (pop corn salt, prepared by using food processor and regular salt) to those area and let it stay in the carpet for 2 days and it seem to help 3 out of the 4 area. As of now, I have DE on all the carpet and just waiting for it to kill the Rest of the fleas (may be another couple weeks?). In the tiles area, keeping a layer of DE in our busy kitchen is an impossible task. So I just vacuumed the til floo o remove those fleas. Given our experience so far, if we were to have fleas again, I would 1) apply a combination of boric acid/fine salt/baking soda for the carpet