Some hallways in the house may have runners or various throw rugs near doors that lead into the house. Take a moment to wash these throw rugs, remember to check to make sure they are machine washable.
If your synthetic rugs can fit in the washing machines, feel free to wash them there. If they cannot fit then perhaps use your bathtub. In the washing machine, use cold water and choose the delicate cycle. It is best to probably drip dry them by hanging them outside on a sunny day.
Here is a video from Essortment