Filtration efficiency of industrial vacuum cleaners - testing method

This study involves industrial vacuum cleaners categorized in class H (the most restrictive according to the standard EN 60335-2-69), which are likely to be used to collect types of dust that are harmful to health (silicon, asbestos, etc.). The study confirms the feasibility of a method which implements a fluorescein aerosol for measuring a so-called confinement efficiency taking into account both airtightness with respect to aspirated dust particles and filtration system efficiency. Fluorescein is easily detectable at low concentrations and therefore allows appliances with, in principle, high-performance characteristics to be tested without the constraints associated with other evaluation methods. Use of fluorescein allowed us to conduct tests involving a sampling time of approximately half an hour which could be optimized with a much higher accuracy than that of the gravimetric measurement method. The method has been validated using five vacuum cleaners currently available on the market, which were selected from appliances designed for maintenance work in the presence of asbestos.