Continuous Emission Monitoring Systems (CEMS)

CEMS continuously measure stack gas parameters — including flow velocity, gas composition, opacity, and pollutant concentrations — and report this data to regulatory agencies. Their primary function is to ensure ongoing compliance with air quality standards, support mass emissions reporting (e.g., pounds of NOx per day), and provide operators with real-time process data for combustion control and operational efficiency.

No. OSI's optical flow sensors are factory pre-calibrated using a NIST-certified algorithm and are drift-free by design. The sensors feature built-in automatic calibration checks and continuous self-test diagnostics, meaning no field calibration is ever required. This significantly reduces operational costs and eliminates calibration-related downtime throughout the sensor's service life.

EPA 40 CFR Part 75 governs continuous emissions monitoring at electric generating units and other major combustion sources. OSI's OFS series optical flow sensors are fully compliant with EPA 40 CFR Part 75 requirements for stack gas flow measurement, providing certified, audit-ready data that satisfies regulatory reporting obligations for emissions trading and permit compliance programs.

Yes. OSI offers purpose-built models for challenging environments. The OFS-2000W features Automatic Gain Control (AGC) for wet scrubbers and bag houses with high moisture or particulate opacity. The OFS-2000F covers flare stacks with an extended velocity range of 0.03–170 m/sec. All models use non-intrusive optical scintillation, making them unaffected by temperature, pressure, dust, or moisture variations.

OSI's standard OFS-2000 and OFS-2000W sensors achieve ±2% accuracy over a 0–100 m/sec velocity range. The OFS-2000F model, designed for flare stacks, extends the range to 0.03–170 m/sec at the same ±2% accuracy. All sensors operate from -50°C to 60°C and are unaffected by changes in temperature, pressure, gas density, or moisture content.

OSI optical flow sensors serve power plants, petroleum refineries, chemical plants, aluminum smelters, incinerators, and waste-to-energy facilities. Specific applications include thermal oxidizers, flare stacks, wet scrubbers, bag houses, glass furnaces, sulfur recovery units, catalytic crackers, carbon capture systems, and terminal loading facilities requiring mass emissions monitoring for regulatory compliance.