Trolley-mounted instrumentation for testing air filters

摘要

The unit tests filters used for air cleaning. It passes a flow of ambient air (3) containing impurities through a test filter, taking a sample before and after so doing. An instrument measures and records physical data from the air stream. A novel feature is a trolley (1) carrying the equipment. Also claimed is the method, of which an essential feature is the use of only ambient air in the test, which is therefore only contaminated with naturally-occurring impurities (or those peculiar to the specific environment). Preferably, each typically has a concentration below 1 mu g/m<3>. The section taking the samples comprises two separately-operated air scrubbing stations. The trolley has rollers (2), mounted for pivoting and braking. The test filter is fixed by standardised fastenings in a filter chamber. The instrument includes sensors for the moisture, temperature, flow velocity, and pressure of the air stream.