The Irish Atmospheric Simulation Chamber (IASC) facility is a comprehensive and ambitious upgrade of a smaller, first generation chamber. The custom-built chamber is a ~25 m³ cuboid made of FEP Teflon foil, supported in a frame and surrounded by a temperature-controlled enclosure fitted with 140 UV (A & B) lamps for photolysis measurements. The facility is equipped with a comprehensive range of instruments for continuous online measurements of gases and particles. The detection capabilities of IASC for this project will comprise commercial gas analysers for O₃ and NO_X, a scanning mobility particle sizer (SMPS) to measure particle number and size distribution, and a state-of-the-art Time-of-Flight Chemical Ionisation Mass spectrometer (ToF-CIMS) for analysis of gas and particle phase organic compounds. The versatile and highly instrumented nature of the infrastructure makes it an ideal test bed for new atmospheric monitoring technologies and sensors under controlled (not field) conditions.