Reducing the risk of particulate matter containing asbestos using a high-efficiency, low-differential pressure system

Abstract

The Purpose of this study was to improve the efficiency of filters used in asbestos control systems, such as those used at asbestos removal sites. We evaluated the melt-blown (MB) filter media for their asbestos removal efficiencies. The filter grades were based on the ISO and European standards (EN 1822) of E12 (≥99.5% collection efficiency) and H13 (≥99.95% collection efficiency) with a size of <0.2 μm asbestos diameter. Based on test chamber experiments, the asbestos removal efficiency of the grade H13 MB filter (99.974%) was higher than that of the E12 grade MB filter (97.120%). In addition, the lowest level of pressure drop was observed in the case with a 3.8 mm pitch interval. The concentrations of airborne asbestos based on phase contrast microscopy in the sites with asbestos concentrations presenting high risks before turning on the asbestos control system was 0.038 fiber cm−3 at demolition site A and 0.027 fiber cm−3 at demolition site B. Chrysotile asbestos was detected at both demolition sites A and B before turning on the system, but were not detected after using the system. Therefore, MB filters present an efficient alternative to current commercial filters and should be considered for use in asbestos removal applications.