Element offers a complete range of stack emissions testing, environmental inspection, and consultancy services to help organizations achieve total regulatory compliance for industrial installations.

Operators producing emissions to air from stacks and other source releases are required to comply with Emissions Limit Values (ELVs) and Quality Assurance of CEMS as specified in their regulatory monitoring requirements, such as EU Industrial Emissions (IED) & Medium Combustion Plant (MCP) Directives, US Clean Air Act, Permit & License monitoring requirements.


MCERTS stack emissions testing and monitoring 

Element are the largest ISO 17025 UKAS-MCERTS accredited organization in the UK & Ireland, operating from 10 regional offices with 42 teams.

Key Features of our class-leading emissions service include: 

  • People - Largest pool of MCERTS certified emissions experts in the UK (Level II with all 4 Technical Endorsements). 
  • Geographic Coverage - Engineers based across 10 regional offices to quicken operations, maintain competitive rates and provide value for money. 
  • Accreditation - Largest scope of UKAS Accredited Tests in the UK covering all the main parameters but also other, less common, compounds including Chrome VI, Isocyanates, Siloxanes, Bioaerosols, Speciated VOCs such as Phenols and Cresols, Sulphuric Acid Mist, Odour, HCN, H2S along with other trace and bulk gas components.  
  • Centre of Technical Excellence – Each year we conduct over 300 EN 14181 CEMS QAL2 and AST campaigns and all this knowledge, practical experience and best practice is focused in our new hub with the aim of delivering the best possible advice and trusted solutions for CEMS Quality Assurance and Verifications.
  • Calibration Workshop – We maintain, calibrate and performance check all of our sampling equipment ourselves. For example, over 60 FIDs, over 60 Horiba Combustion Gas Analysers, and around 70 Manual Isokinetic Sampling Systems. This gives us a greater understanding of how the equipment works leading to more accurate and repeatable emissions data. 
  • In-House Analysis of Samples by Element laboratories – Some stack emissions testing requires extractive.
  • e-Mission Digitial Portal to manage all aspects of your emissions requirements through an on-line system designed by Element. 

We provide independent, accredited stack emissions testing, which is essential for all organizations that wish to meet their regulatory compliance responsibilities.

Contact us for more information.

Maritime Emissions Monitoring

Maritime Emissions Monitoring 

International Maritime Organization (IMO) regulations have been tightened in recent years to limit air emissions from ships and other maritime vessels. Maritime air pollution control is now much more closely aligned with shore-based power plants and industrial sites.

Our ISO 17025 UKAS-MCERTS accredited emissions testing methods monitor maritime emissions highlighted in the MARPOL Annex VI Regulations, aimed at controlling pollutants such as NOx, SOx and CO2. 

Element work in collaboration with marine fuel additive companies to provide the sector with independently verified reductions in carbon emissions and fuel consumption. We have a proven track record of successfully delivering maritime projects, and our experience of testing on ships and vessels allows us to provide the accurate advice you need. 

Biogas Combustion Emissions

Continuous Emissions Monitoring Systems (CEMS) - EN 14181 Quality Assurance & Verification

EN 14181 is a European Standard covering Quality Assurance of Continuous Emissions Monitoring Systems (CEMS) and focuses on calibration, testing and verification. The standard has 4 main sections:










Quality Assurance Level 1




On Purchase


Demonstrating the CEM is suitable and fit for purpose.


Quality Assurance Level 2




Commissioning &
Every 5 Years


Ensuring the CEM is set up correctly and calibrated.


Quality Assurance Level 3






Ongoing Quality Assurance of Performance of CEM


Annual Surveillance Test




Annual between QAL2s


Annual assessment check of Calibration Functions


*CEMS are also sometimes referred to as AMS (Automated Measuring Systems). 

The QAL2 has 3 steps: 1) Functional Tests & Linearity Checks, 2) Parallel measurements using Standard Reference Methods (SRM) and CEMS data and 3) Data handling. 

There should be a minimum of 15 parallel measurements spread over 3 days to maximise a good spread of data and at least one results near zero. 

Data handling is also vitally important.  As the Time Series plot graph below shows, the parallel data (SRM & CEM) are converted to the same conditions and a Calibration Function is derived via linear regression.

There are 3 methods used to derive a valid Calibration Function: 

  • Method A – Used when you have a good spread of data (Linear Regression). 
  • Method B - Used when you have a high level cluster (Linear Regression through zero). 
  • Method C – Used when you have a low level cluster (Surrogates used). 

A Variability Test is carried out looking at the difference between the Calibrated CEM and SRM and a Pass or Fail is reported. 

QAL3 focusses on ongoing Quality Control and determination of SAMS (Standard Deviation of the AMS) by regular zero and span checks.  It is important to clarify that the analyser isn’t adjusted, just checked.  Results are plotted on Control Charts either as CUSUM (Cumulative Sums) or Schewart (good at detecting changes in a measurement mean or variance) and show the drift of a CEM over time.  Warning Limits and Action Limits are set and prescriptive procedures for dealing with out of control situations. 

Annual Surveillance Test (ASTs) are a yearly check and like a ‘mini QAL2’.  Functional and Linearity Checks are performed along with a reduced set of Parallel Measurements.  At least SRM measurements are taken over 1 day and results are checked for Variability and against the current Calibration Function. 

Air Quality Testing

Odour Monitoring

Many facilities are required to operate under an Odour Management Plan (OMP) as part of their Environmental Permitting Regulations and to prove Compliance. Other processes may just require an assessment of the performance of odour control units or to investigate an odour complaint.

Odour pollution can be complicated to assess and measure as often several substances are involved and multiple factors in play including the concentration, intensity and site specific / time dependent factors. 

For Point Sources (Stacks) Odour is measured to the European Odour Standard EN 13725:2003 for which Element are UKAS Accredited. This determines the odour concentration by dynamic olfactometry, where odour is assessed from the point of view of perceptibility to human olfactory sense. 

We can collect samples using a non-reactive material and a sampling technique that prevents potential sources of contamination. The sample is rapidly assessed by an odour panel within 30 hours of sampling. Results are then calculated in the form of European odour units, and assessment of the hedonic tone, if necessary. 


Audit training 

In addition to stack emissions testing and compliance services, Element also offers audit training e.g. Operator Monitoring Assessment (OMA) to prepare for an Environment Agency audit visit. Audit training can help ensure your audit will be carried out effectively and efficiently, resulting in an accurate representation of the standard of self-monitoring. 

The Element advantage 

We conduct more EN 14181 QAL2 and ASTs than anyone else in the UK. Our newly formed Centre of Technical Excellence acts as a hub to share best practice and knowledge from our vast experience conducting tests with the full spectrum of different types of CEM. 

With this complex, technical emissions testing trust our Element experts and the number one provider of this service. 

We have specialized in-house training programmes targeted at excellence in the details, intricacies and methods A, B & C for deriving calibration functions for EN 14181.

Our goal is to help you achieve regulatory compliance, meet your environmental goals, and support reduced emissions to improve Air Quality.

For more information about our stack emissions testing, or to know more about our MCERTS accredited stack emissions testing services, contact us today. 

Our stack emissions testing and compliance services include:  

We provide all types of stack emissions testing using manual reference and alternative methods, instrumental analyzers, and FTIR including;

  • Particulate Matter, PM10 & PM2.5
  • Combustion Gases (NOX, NO, NO2, N2O, SO2, CO, CO2, VOCs & TOC)
  • Trace Pollutants (Dioxins & Furans, PCBs & PAHs, Metals & Mercury, Hexavalent Chromium)
  • Acidic Gases & Vapors (HCl, HF, NH3, HCN, H2S, Sulphuric Acid Mist, Nitric Acid Vapor)
  • Organic Compounds (Specific VOCs, Formaldehyde & Aldehydes, Isocyanates, Oil Mist, Tar & Bitumen Fume)
  • Odour
  • Bioaerosols
  • Biogenic Fraction CO2

Element performs stack emissions testing to the following standards:

Pollutant European Standards US EPA (CFR) Standards
Aldehydes US EPA Method 316 US EPA Method 316
Ammonia EN 14791
Bioaerosols VDI 4257
Biogenic Fraction CO2 EN ISO 13833
Carbon Dioxide ISO 12039
Carbon Monoxide EN 15058
Condensable VOCs In house accredited method
Dioxins and Furans EN 1948
Dioxin-like PCBs
EN 1948:4
US EPA Method 316
Gaseous Species by FTIR TGN M22 (Flexible Scope)
Halides and Halogens
US EPA Method 26/26A
US EPA Method 26/26A
Heavy Metals EN 14385
Hexavalent Chromium EN ISO 23210
Homogeneity EN 15259
Hydrogen Chloride
EN 1911
Hydrogen Cyanide
Hydrogen Fluoride ISO 15713
Hydrogen Sulphide
US EPA Method 11
US EPA Method 11
lsocyanates US EPA CTM 36

EN 13211
Nitric Acid Vapour
US EPA Method 7D
Nitrous Oxide
EN ISO 21258

EN 13725

Oil Mist, Tar and Bitumen Fume
EN 13284-1 with MDHS 84

Oxides of Nitrogen
EN 14792

EN 14789

ISO 11338

PM10& PM2.5
EN ISO 23210

Pressure, Temperature, and Velocity
EN 16911-1
Speciated VOCs
PD CEN/TS 13649

Sulphur Dioxide
EN 14791

Sulphur Dioxide
CEN/TS 17021

Total Particulate Matter
EN 13284-1

Total VOCs (TOC)
EN 12619

Water Vapour EN 14790

Total environmental compliance

Test, track and trend your stack emissions data with our industry leading digital portal.

With e-Mission, Element continues to innovate in the field of emissions monitoring. 

Read more about how our emissions platform offers a clearer picture of your environmental status, provides the ability to spot trends and identify issues to reduce the risk of non-compliance.


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