Also used for construction and air purifying for residential, industrial, education, commercial and institutional settings. HEPA filter removes 99.99% of .1-.5 micron particulates, the most harmful size for humans to breathe. Quieter operation for use in any occupied spaces. Lightweight and stack securely for compact storage and transport. Command Hub enables fine-tuning of airflow and monitoring status of HEPA filter. Rugged injection-molded housing with limited lifetime warranty.