NADCA (National Air Duct Cleaners Association), the American Association founded in 1989 that combines the companies engaged in the assessment, cleaning and restoration of HVAC systems, and AIISA (Italian Association of Hygienists Systems Aeraulic) its referent Italian, promote worldwide the culture of indoor air quality. Such associations shall, to the technicians who pass a rigorous examination, certification ASCS (Air System Cleaning Specialist) that certifies the knowledge in the field of remediation of HVAC (Heating, Ventilation and Air Conditioning), knowledge of procedures NADCA (National Air Duct Cleaners Association) safety standards relating to work on. The ASCS certification not only emphasizes professional development, but it is also an international credential that recognizes a professional knowledge and competence relating to the hygiene of HVAC systems. NADCA has developed a standard (ACR), which defines the procedure for cleaning procedure to test and establish acceptable levels of cleanliness to which every specialist should follow.
