The widespread use of fibreglass and similar products for noise control, especially in HVAC systems, has been a cause of concern for health ever since asbestos fibre was shown to be hazardous. Although the asbestos manufacturers finally accepted that they inadvertently caused illness and death, and paid out huge compensation, fibreglass manufacturers protest the innocence of their product. In North America, the pro-fibreglass campaign has been led by the North American Insulation Manufacturers Association (NAIMA).