Environmental Glossary

Definitions of key terms used in stack emissions testing, air quality assessment, noise monitoring, odour assessment, and environmental permitting in the UK.

A B C D E F G H I L M N O P Q S T U

A

ADMS: Atmospheric Dispersion Modelling System — software used to predict how pollutants disperse from emission sources. Widely used in the UK for planning and permit applications. Learn more →
AEGL: Acute Exposure Guideline Levels — threshold concentrations for airborne chemicals above which adverse health effects are predicted for the general population.
AERMOD: American Meteorological Society/EPA Regulatory Model — a steady-state dispersion model used internationally for regulatory air quality assessments.
Air Quality Management Area (AQMA): An area designated by a local authority where air quality objectives are not being met or are at risk. Developments in or near AQMAs typically require Air Quality Assessments.
Air Quality Neutral (AQN): A GLA planning policy requiring developments to demonstrate that transport and building emissions are below benchmark levels.
Ambient Air Monitoring: Measurement of pollutant concentrations in the outdoor environment, as opposed to at an emission source. Methods include diffusion tubes, MCERTS automatic analysers, and gravimetric samplers. Learn more →

B

BAT: Best Available Techniques — the most effective and advanced methods to prevent or minimise pollution, as defined under the Industrial Emissions Directive.
BREEAM: Building Research Establishment Environmental Assessment Method — a sustainability rating scheme that includes indoor air quality testing credits (Hea 02). Learn more →
BS 4142: British Standard for assessing industrial and commercial noise impact on residential receptors. Compares rated noise levels against background sound levels. Learn more →
BS 5228: British Standard for noise and vibration control on construction and open sites. Used for predicting construction noise levels and specifying mitigation.
BS 8233: British Standard providing guidance on sound insulation and noise reduction for buildings. Often referenced in planning conditions for residential developments.

C

CEMS: Continuous Emissions Monitoring System — permanently installed analysers that measure stack emissions 24/7. Required for large combustion plant, EfW, and some IED installations. Learn more →
CEMP: Construction Environmental Management Plan — a document setting out how environmental impacts will be managed during construction, often a planning condition.
CO: Carbon monoxide — a common pollutant measured in stack emissions testing and ambient air quality monitoring.
COSHH: Control of Substances Hazardous to Health — UK regulations requiring employers to assess and control workplace exposure to hazardous substances.

D

Diffusion Tube: A passive sampling device for measuring ambient NO2 concentrations over a period (typically monthly). Widely used in UK local authority air quality monitoring networks.
Dioxins and Furans (PCDD/F): Highly toxic persistent organic pollutants formed during combustion processes. Measured using long-term sampling methods (BS EN 1948) at waste incineration and EfW plants.
DMP: Dust Management Plan — sets out measures to control dust emissions from construction or demolition sites. Often required as a planning condition.

E

EA: Environment Agency — the environmental regulator for England. Responsible for issuing Environmental Permits, compliance assessment, and enforcement.
EfW: Energy from Waste — facilities that recover energy from the combustion of waste materials. Subject to stringent IED emission limit values and MCERTS monitoring requirements.
EIA: Environmental Impact Assessment — a formal assessment of the likely environmental effects of a proposed development, required for certain project types under the EIA Regulations.
ELV: Emission Limit Value — the maximum concentration or mass emission rate of a pollutant permitted under an Environmental Permit.
EN 13284-1: European Standard for gravimetric measurement of particulate matter (dust) from stationary sources.
EN 13725: European Standard for olfactometry — the reference method for determining odour concentration using a panel of trained human assessors.
EN 14181: European Standard for quality assurance of automated measuring systems (CEMS), covering QAL1, QAL2, QAL3, and AST requirements.
EN 14385: European Standard for measurement of heavy metals from stationary source emissions.
EN 1948: European Standard for measurement of dioxins and furans (PCDD/F) from stationary sources, using long-term or short-term sampling methods.
EPR: Environmental Permitting Regulations 2016 — the UK legal framework requiring Environmental Permits for prescribed industrial activities, waste operations, and water discharges.
EPUK: Environmental Protection UK — a charity providing guidance on air quality, land quality, and noise. Co-authors (with IAQM) of the widely used planning guidance for air quality assessment.

F

FTIR: Fourier Transform Infrared spectroscopy — an analytical technique used in stack emissions testing to simultaneously measure multiple gas compounds. The portable FTIR analyser is the industry-standard portable FTIR analyser.

G

Gravimetric Sampling: A method of measuring particulate matter by collecting dust on a filter and weighing it. Used for both ambient air monitoring and stack emissions testing.

H

H1 Assessment: Environment Agency guidance for determining the appropriate stack height for new installations. Uses dispersion modelling to ensure ground-level concentrations are acceptable. Learn more →
H4 Assessment: Environment Agency guidance for assessing odour impacts as part of Environmental Permit applications. Requires quantified odour emission rates and often dispersion modelling.
HCl: Hydrogen chloride — an acid gas commonly measured in stack emissions from waste incineration, chemical manufacturing, and glass production.
HRA: Health Risk Assessment — an evaluation of the potential health effects of pollutant exposure on local populations, often required for waste facilities and large industrial installations.

I

IAQM: Institute of Air Quality Management — a professional body providing technical guidance on air quality assessment, odour assessment, construction dust, and mineral dust. IAQM guidance is widely referenced in UK planning policy.
IED: Industrial Emissions Directive (2010/75/EU) — the main EU directive governing pollutant emissions from industrial installations. Transposed into UK law via the Environmental Permitting Regulations.
Isokinetic Sampling: A stack emissions sampling technique where the sample is drawn at the same velocity as the flue gas, ensuring representative collection of particulate matter and associated pollutants.
ISO 17025: International standard specifying requirements for the competence of testing and calibration laboratories. UKAS accreditation to ISO 17025 is the gold standard for stack emissions testing laboratories.

L

LAQM: Local Air Quality Management — the framework under which UK local authorities assess and manage local air quality against national objectives.

M

MCP: Medium Combustion Plant — combustion plants between 1MW and 50MW thermal input, including generators, boilers, and CHP units. Subject to MCP Directive permitting requirements. Learn more →
MCERTS: Monitoring Certification Scheme — the Environment Agency's performance standard for environmental monitoring. MCERTS accreditation ensures testing methods, equipment, and laboratories meet required quality standards. Learn more →

N

NO2: Nitrogen dioxide — a key air quality pollutant regulated under UK ambient air quality standards. Primary sources include road traffic and combustion processes.
NOx: Nitrogen oxides (NO + NO2) — major pollutants from combustion sources, measured in both stack emissions testing and ambient air quality monitoring.
NRW: Natural Resources Wales — the environmental regulator for Wales, equivalent to the Environment Agency in England.

O

Olfactometry: The measurement of odour concentration using calibrated human panels following EN 13725. Provides odour emission rates in ouE/m³ for use in dispersion modelling.
OMA: Operator Monitoring Assessment — the Environment Agency's scoring system for evaluating the quality and credibility of an operator's emissions monitoring programme.

P

PM10 / PM2.5: Particulate matter with aerodynamic diameter less than 10 or 2.5 micrometres. Key air quality pollutants associated with adverse health effects. Monitored in ambient air and at construction sites.
PI: Pollution Inventory — the Environment Agency's database of annual pollutant releases from regulated facilities. IED Chapter II operators must report annually by 31st January.

Q

QAL2: Quality Assurance Level 2 — a calibration procedure under EN 14181 that validates CEMS against reference methods (stack testing). Required after CEMS installation and periodically thereafter. Learn more →
QAL3: Quality Assurance Level 3 — ongoing drift and precision checks for CEMS under EN 14181, using control charts to detect instrument degradation.

S

SCR: Selective Catalytic Reduction — an exhaust gas treatment technology that reduces NOx emissions using a catalyst and ammonia/urea reagent.
SEPA: Scottish Environment Protection Agency — the environmental regulator for Scotland.
SO2: Sulphur dioxide — a pollutant from combustion of sulphur-containing fuels, regulated in both stack emissions and ambient air quality.
STA: Source Testing Association — the UK trade body for the stack emissions testing industry. STA members commit to quality standards and best practice.

T

TOC / VOC: Total Organic Carbon / Volatile Organic Compounds — organic pollutants measured in stack emissions and ambient air. Sources include chemical manufacturing, printing, coating, and waste treatment.

U

UKAS: United Kingdom Accreditation Service — the sole national accreditation body recognised by government. UKAS accreditation to ISO 17025 confirms a laboratory's competence and impartiality.
UK ETS: UK Emissions Trading Scheme — the UK's carbon trading system replacing the EU ETS post-Brexit. Requires verified CO2 emissions reporting from eligible installations.