The GTS 114 was developed with the aim of testing filters with different shapes (filter cartridges, cassette filter, filter with filter bags and plane filter media) using varying test aerosols (salt, oil) under adjustable air conditions (air humidity, temperature) within the test duct. By using the test system the following filter characteristics can be determined: differential pressure curves, dust holding capacity, gravimetric efficiency, fractional efficiency, salt removal efficiency (ISO/AWI 29461-4) and water endurance (ISO 29461-2).