Hazardous material vacuums are equipped with a HEPA filter system consisting of a certified absolute filter, a double layer intermediate micro filter, and a totally enclosed 2-ply disposable paper filter bag. The HEPA filter has a steel outer casing and micro-fibered glass paper filter media separated by corrugated aluminum sheeting that is encased in a protective steel screen. All HEPA filters are rated with a minimum efficiency of 99.97% at 0.3 microns. Poly motor head enclosure with 2 year warranty.