Certified Engineered wood fiber or playground wood chips are a superior quality wood-fiber material. It is made from 100% virgin wood fiber, not recycle used wood. Which may contain things you do not want in your playground. Our material carries a certification of purity. It is fall protection effectiveness is grounded in the physics of wood chips. When it is laid, the finer wood chips sink to the bottom creating soft bedding for the larger pieces on the top. This natural “layering” provides buoyancy that cushions the impact of a fall and ensures quick drying.