An airnet constructed of a filtering fabric sewn in the shape of a windsock is connected to the discharge end of a fan. Actuation of the fan causes ambient air to flow through the fan and into the airnet. The air passes through the filtering fabric of the airnet and particulate matter in the ambient air is trapped and retained within the airnet. The airnet and fan combined form a portable air filtration system capable of filtering the ambient air in confined spaces, such as bathrooms being finished or remodeled, in a relatively quick and efficient manner.