Monitoring stack emissions: standards for continuous monitoring and sampling
This guidance specifies the standards for the continuous monitoring and sampling of stack emissions.
Applies to England
This guidance specifies the standards related to the:
- quality assurance of continuous emissions monitoring systems (CEMS) and their associated data acquisition and handling systems (DAHS)
- long-term samplers (LTS)
- quality assurance of predictive emissions monitoring systems (PEMS)
Standards for calibration of CEMS
You can use CEMS for continuous emissions monitoring.
Flow
You can monitor flow using CEMS.
The relevant monitoring standard is EN 16911-2.
EN 16911-2 covers the calibration of flow monitoring CEMS. It is used in conjunction with EN 14181.
Mercury
You can monitor mercury using CEMS.
The relevant standard is EN 14884. It covers the calibration of mercury CEMS. It is used in conjunction with EN 14181.
Particulate matter
You can measure particulate matter using CEMS.
The relevant standard is EN 13284-2. It covers the calibration of CEMS that measure particulates. It is used in conjunction with EN 14181.
You can also measure particulate matter using dust arrestment plant monitors.
The relevant standard for the calibration of dust arrestment plant monitors is EN 15859.
Quality assurance of CEMS
The relevant monitoring standard is EN 14181. It covers the certification, calibration, and ongoing quality assurance of CEMS. It applies to all determinands measured with CEMS.
Standard for DAHS
You can use DAHS to handle and report data from CEMS.
The relevant standard for the ongoing quality assurance and control of DAHS is EN 17255-4.
Standards and techniques for LTS
You can use LTS to provide a continuous sample for periods of typically 2 to 4 weeks. You can use them to provide continuous sampling during the periods that a process operates. Each sample is analysed in a laboratory. This provides a single time-averaged result over each sampling period.
Dioxins, furans and dioxin-like polychlorinated biphenyls
You can use LTS to measure dioxins, furans and dioxin-like polychlorinated biphenyls.
You do isokinetic sampling, extraction, and then gas chromatography–mass spectrometry analysis.
For this technique:
- you obtain time-integrated samples over averaging periods typically ranging from 14 to 28 days
- a sample is obtained continuously but the results are not instantaneous as you need to take the filter and absorption media to a laboratory for analysis
The relevant monitoring standard is CEN TS 1948-5.
Mercury
You can measure mercury using LTS.
This LTS uses paired sorbent media traps. Analytical techniques include:
- cold vapour automatic fluorescence spectrometry
- cold vapour atomic absorption spectroscopy
This technique measures total vapour phase mercury, which represents the sum of the elemental mercury and gaseous forms of oxidized mercury, such as mercury chloride.
Although a sample is obtained continuously, results are not instantaneous as you need to take the sorbent media traps to a laboratory for analysis.
The relevant monitoring standard is CEN TS 17286.
The standard applies to both short term periodic monitoring and long-term sampling. It includes performance criteria and test procedures for certifying long-term sampling systems. It also includes procedures for evaluating the ongoing performance of the installed systems.
Biogenic carbon dioxide
You can measure biogenic carbon dioxide using LTS. You sample carbon dioxide, followed by analysis of the percentage of biogenic carbon dioxide in the sample.
You use flow proportional sampling, extraction, and then analysis by accelerator mass spectrometry, liquid scintillation or beta ionization.
For this technique:
- you obtain time-integrated samples over averaging periods of typically 28 days
- a sample is obtained continuously but the results are not instantaneous as you need to send the absorption media to a laboratory for analysis
There is no published monitoring standard but you can apply the principles of the periodic manual method (CEN 13883).
Standard for PEMS
You can use PEMS for determining emissions by using relationships or models for the emission with corresponding continuously available process parameters.
You can use PEMS to predict real time emissions levels from a model based on previous results. This provides an alternative to carrying out ongoing stack emissions measurements.
The relevant monitoring standard is CEN TS 17198.