This case involves a group of construction workers that were exposed to asbestos during the renovation of a brewery located on an industrial site. The project manager was aware of the risk of asbestos on site and mandated that all workers wear respirators while on site. The respirators used were marketed to filter small particles and prevent lung disease. In spite of consistent respirator use, many of the workers have developed asbestos-related complications, including mesothelioma. An expert in aerosol physics was sought to discuss the industry standards for respirators and testing methodology to determine if the filters were sufficient enough to withstand degradation.