OI-520 Calibration Station

The Otis Instruments, Inc. Model OI-520 Calibration Station is a precision gas blender that simplifies the calibration of air quality instruments. The OI-520 is able to blend a wide range of calibration gas levels from a single cylinder. This feature saves money by substantially reducing the number of calibration gas cylinders required and often eliminating the need for zero air cylinders. The OI-520 blends conditioned ambient air with a precisely controlled flow of an elevated concentration of toxic gas to provide the ppm level of the calibration gas desired by the user. The device also permits the use of conditioned ambient air—air from which interfering gases have been removed as an accurate “zero” air calibration gas, even in the presence of atmospheric contaminants.