OCI oil content indicator has been designed to monitor oil content in pressure vessels and receivers where air quality is critical. It is calibrated to detect aerosol-mist level of oil with sensitivity down to 0,01 PPMm (0,012 mg/m ?). Replacement cartridge is available when original is worn out. For applications not listed or for any other technical gas please contact National Filters or your local distributor. Prices Exclude GST.