Article: Diatomaceous earth (DE) comes in two forms. Most DE sold as a pest control treatment or labeled "food-grade" is safe for home use and not linked to serious health issues. Never use pool grade or industrial grade DE in your home, since these forms can (eventually) cause permanent respiratory problems.  All DE products are actually a mix of the "safe" and "unsafe" types. Food grade DE still has a small amount of "unsafe" DE, and is still dangerous if inhaled in large quantities. DE sold for pest control has to meet specific safety standards and list safe instructions on the label (at least in the US), so this is usually the best choice. Food grade DE may not have a detailed safety label, since it is not intended to be used in pure, dry form, but it is similar to pest-grade DE and the risk of harm is low with the precautions below. Since food-grade DE is meant to be stirred into food and eaten, some people assume it is completely safe. However, the concentrated, dry powder can seriously irritate the lungs, eyes, and skin. Review these safety precautions before you begin:  Always wear a dust mask at minimum, since inhalation is the main danger. A respirator mask is much better, especially if you plan to use DE many times.  Wear gloves, eye protection, long sleeves, and long trousers. Keep children and pets away from the carpet while the diatomaceous earth is there. Consider testing a small area first, following the instructions below. Assuming there are no negative reactions from you our your household members, repeat on the rest of the carpet. Professional pest controls use special dusters to put down a fine, even layer of dust, but these can be hard for consumers to find. You can use a feather duster, paint brush, or flour sifter instead. Spoon (don't pour) the DE onto the dusting tool slowly, to avoid a cloud of dust. Squeeze bottles or bellows are not recommended, since they cause too much drifting.

What is a summary?
Use pest grade or food grade diatomaceous earth. Follow safety instructions. Choose a dusting tool.