To test to make sure that you're not allergic or overly sensitive to a new carpet that you'd like to install in your home, ask the retailer for a small sample piece from the roll that they'd be using to carpet your home. Put the piece of carpet into a container and seal it up. Leave the container—clear glass works best for this—in a warm sunny area for a few days; after the sample has had time to out-gas, open it up and check it for irritating odors. Don't forget to do a touch test to see if you have any contact sensitivities to it as well.