Continuous Emissions Monitoring (CEMS) Engineering
Continuous Emissions MonitoringContinuous emissions and flaring measurement for regulated sources.
Permanently installed, automated monitoring of exhaust-gas and stack emissions. FUTUREGAZ supports CEMS engineering, data structuring, and compliance documentation across industrial and maritime operations.
Analyser-based CEMS — the configuration covered on this page — combine one or more analysers, either mounted in-situ at the stack or served by an extractive system that conditions and transports a sample to the analyser, with a data acquisition and handling system (DAHS) that produces a continuous, timestamped record of concentration, opacity, and/or flow. Which compounds and parameters must be measured, to what quality-assurance standard, and how the resulting data must be reported depend on installation type, jurisdiction, and source category — and, for IED-regulated installations, on permit conditions. That detail follows below, organised first by industry (Where CEMS applies) and then by regulatory framework (Applicable regulatory frameworks).
What we deliver
Measurement system design and review
Extractive versus in-situ system selection, probe positioning, sample conditioning, analyser specification, and flow measurement integration. Includes DAHS (Data Acquisition and Handling System) architecture review.
Compliance documentation
Structuring of continuous emissions datasets for regulatory submission. Covers data availability reporting, exceedance identification, and evidence packaging aligned to IED, EPA 40 CFR Part 75, EU ETS, and MARPOL Annex VI requirements.
Quality assurance: QAL and calibration
QAL1 suitability assessment support, QAL2 field calibration planning, QAL3 drift and precision monitoring, and Annual Surveillance Testing under the applicable CEMS quality framework. Calibration traceability from certified reference materials to instrument records.
DAHS data structuring and integration
Integration of raw analyser output into structured DAHS records with timestamps, quality flags, missing data substitution logic, and averaging period definitions aligned to applicable reporting requirements.
What CEMS measures and what it does not change
CEMS provides continuous, instrument-based evidence of emissions concentration and mass flow at the stack. It replaces or supplements calculation-only and periodic-testing methods with real measurement.
Continuous measurement evidence
Verified concentration data for each regulated compound at defined time resolution. Stronger evidentiary position than fuel-based estimation, default emission factors, or periodic testing alone. Required under the IED for specified sources — Article 38 with Annex V Part 3 for large combustion plants, and Article 48 with Annex VI Part 6 for waste incineration and co-incineration plants — and under EPA 40 CFR Part 75 for affected units. Under MARPOL Annex VI, continuous monitoring applies through specific routes rather than as a general requirement — for example, through EGCS Scheme B, or as an optional data source for the NOx direct measurement and monitoring method.
Not a substitute for abatement
CEMS records what is emitted; it does not reduce it. Improvements in emissions performance require operational or technical changes: fuel quality, combustion tuning, flue gas treatment. CEMS provides the data to evidence that change, not the change itself.
Where CEMS applies
Power generation
Coal, gas, and biomass-fired plant under IED and EPA Part 75. Large combustion plant NOx, SO₂ and dust emissions must be measured continuously at ≥100 MWth under IED Annex V Part 3, subject to the derogations there (including for SO₂ from gas- and biomass-fired plant), with CO₂ monitored and reported under EU ETS and Part 75.
Oil & gas processing
Flaring, combustion turbines, and process heaters at upstream and downstream facilities. Relevant to EU ETS reporting, IED permitting, and EPA NSPS subpart requirements.
Cement & lime
Rotary kilns require continuous NOx, SO₂, CO and dust monitoring under the cement/lime BAT conclusions (2013/163/EU); clinker coolers and cement mills are dust-monitored. High-dust conditions require specialist extractive or cross-stack in-situ designs.
Steel & metals
Sinter plants, blast furnaces, and electric arc furnaces. Dust loading and high temperatures typically call for extractive CEMS designed for high-temperature, high-dust operation, with heated sample lines.
Waste-to-energy / incineration
Among the most demanding CEMS configurations under IED Annex VI: CO, NOx, SO₂, HCl, HF, total organic carbon and dust measured continuously (Annex VI Part 6), against daily and half-hourly emission limit values (Annex VI Part 3), with an additional 10-minute average limit specific to CO.
Chemical & petrochemical
Process combustion, reformers, and large furnaces under IED permit conditions. Integration with DCS and process historians is standard.
Maritime shipping
Onboard emissions measurement is used through two defined routes: as EU MRV Method D (direct emissions measurement, Regulation (EU) 2015/757 Annex I, Part B); and under MARPOL Annex VI — via EGCS Scheme B, or as a data source for the NOx direct measurement and monitoring method. Covers CO₂, NOx and SOx, with the challenges of marine fuel variability, vessel motion, and survey-cycle integration.
Applicable regulatory frameworks
CEMS requirements arise from multiple overlapping frameworks. The applicable standards depend on installation type, jurisdiction, and source category.
US acid rain and emissions reporting
CEMS-based monitoring — with prescribed fuel-based alternatives under Appendices D, E and G — for SO₂, NOx, CO₂, and flow at affected units. Specifies certification testing (RATA), QA procedures, and quarterly electronic data reporting to EPA via ECMPS.
Industrial Emissions Directive
Requires continuous monitoring at large combustion plant (≥100 MWth, with derogations) and waste incineration facilities across EU member states. BAT conclusions define BAT-associated emission levels, which permit writers translate into enforceable emission limit values, and set monitoring requirements.
European QAL framework
Three-level quality assurance: QAL1 (analyser suitability certification), QAL2 (site-specific calibration function), QAL3 (ongoing drift and precision monitoring), and AST (annual surveillance). Standard reference method parallel testing required for QAL2.
Maritime sulphur and NOx
Reg. 13 (NOx) and Reg. 14 (SOx) compliance. Onboard continuous measurement can supply the data for the direct measurement and monitoring method — one of the on-board NOx verification procedures under NOx Technical Code 2008 section 6.4 and Appendix 8 — used to demonstrate Reg. 13 compliance at survey. For SOx, an exhaust gas cleaning system approved by the Administration as an equivalent under Reg. 4 follows the 2021 EGCS Guidelines (MEPC.340(77), superseding MEPC.259(68) for systems delivered from 1 June 2022): Scheme B requires continuous SO₂/CO₂ emission monitoring, while Scheme A relies on unit certification (SOx Emissions Compliance Certificate) plus continuous operating-parameter monitoring and daily emission spot checks; both schemes also require continuous discharge-water monitoring. Reg. 18 is a separate provision covering fuel oil availability and quality, including the FONAR a vessel files when compliant fuel cannot be obtained.
EU carbon market reporting
The EU ETS Directive (2003/87/EC, as amended) permits CEMS as a measurement-based monitoring approach for stationary installations. The EU MRV Regulation (2015/757) has applied to maritime shipping since monitoring year 2018; EU ETS extends to maritime shipping from 2024, phased in at 40% of verified 2024 emissions, 70% of 2025 emissions, and 100% from 2026.
Measurement sections, sites and stack flow
EN 15259 specifies requirements for measurement sections and sites and for the measurement objective, plan and report — it governs whether a stack location is fit to measure at. Volumetric flow itself is determined under EN ISO 16911-1 (manual reference method, which requires measurement locations meeting EN 15259) and EN ISO 16911-2 (automated measuring systems, calibrated against that reference method under EN 14181's QAL2/AST framework, with EN 15259 setting the SRM sample-point grid). Both matter when concentration CEMS is combined with flow CEMS to derive mass emission rate.
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Describe the installation type, source category, applicable regulatory framework, and current monitoring basis. We will assess scope and respond with a structured proposal.
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