you should use the flea stoppers carpet powder. hera are more information
Flea Stoppers Carpet Powder is a specially formulated, mini-granular, Orthoboric Acid. This product is designed to fall freely to the nap of carpets where the fleas live and breed. There are many boric acid flea treatment products on the market today, but don't be fooled, many are dusty and vacuum up within the first week after application. Flea Stoppers Carpet Powder will not lose its effectiveness, even if vacuuming or shampooing occurs. Shampooing does not void our guarantee.
The active ingredient has a desiccant or drying out effect on eggs and larvae.

Female fleas lay their eggs on pets, carpets and furniture. These eggs hatch into a small worm like larvae. Flea larvae feed on the organic powder and die! They never reach the adult stage. The powder also kills any adult fleas that come in contact with the powder in 4 to 6 days. The powder is designed to kill any fleas that are brought into the house by pets. However, pets need to be treated on a regular basis to insure they are flea-free.

As long as label directions are followed, there should be no harmful effects to the people in the house or the pets.

Flea Stoppers Carpet Powder is specially formulated to be dust-free and there is no clean up needed after treatment.

Application for Flea Control
Carpets: Vacuum all carpets thoroughly and dispose of bag. Apply to dry surfaces only. Apply directly on carpets where pets frequently traffic or sleep at a rate of 1 pound per 400 square feet. Work powder deeply into fibers and mat with a broom or a rug rake. Any powder visible after application must be brushed into carpet fibers or removed. Wait 6 - 7 days before vacuuming. Allow 3 to five weeks for maximum flea control. Reapply as necessary. Note: If high adult flea population makes it desirable, apply a pesticide designed to kill adult fleas before or in conjunction with this product.
Upholstery: Remove lose cushions. Apply with approved applicator along creases and into corners and furniture wells. Do not apply to exposed fabric. Any product visible after application should be removed.

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