There are a lot of abbreviations, acronyms and chemical formulas in our line of business. Here are some of them spelled out. You find chemical formulas on the compounds page.

AAQM Ambient Air Quality Monitoring
AAQMS Ambient Air Quality Monitoring Station/Site
AERMOD U.S. EPA-approved atmospheric dispersion model
AMS Automated Measuring System
AQM Air Quality Monitoring
AQMS Air Quality Monitoring Station/Site
AST Annual Surveillance Test
BAT Best Available Techniques, an expression within the IED
BATC BAT Conclusions, the core of a BAT document
CEM Continuous Emissions Monitoring
CEMS Continuous Emissions Monitoring System
CEN French: Comité Européen de Normalisation (European Committee for Standardization)
CUSUM Cumulative sum, a method to monitor drift of instruments
DAHS Data Acquisition and Handling System
DeNOx NOX emissions reduction system (generic)
DeSOx SOX (SO2) emissions reduction system (generic)
DOAS Differential Optical Absorption Spectroscopy – detection principle used in some types of gas analysers
ELV Emission Limit Value
EN European Standard (from German “Europäische Norm”)
EPA Environmental Protection Agency, often on national level, df. U.S. EPA
EWMA Exponentially Weighted Moving-Average
IED Industrial Emissions Directive, an EU regulation
IR Infrared, part of optical spectrum
ISO International Organization for Standardization
MCERTS UK Environment Agency’s Monitoring Certification Scheme for equipment, personnel, and organisations
NAAQS U.S. EPA National Ambient Air Quality Standards
mg/m3 Milligrams per cubic metre
ng/m3 Nanograms per cubic metre
ppm Parts per million
ppb Parts per billion
QA Quality Assurance
QAL Quality Assurance Level, under EN 14181 and EN 15267-3 standards
QC Quality Control
SCR Selective Catalytic Reduction, a flue gas cleaning method
SNCR Selective Non-Catalytic Reduction, a flue gas cleaning method
SRM Standard Reference Method
TDL Tuneable Diode Laser – a light source used in some types of gas analysers
THC Total Hydrocarbons
THg Total mercury, generic term for atomic mercury and mercury compounds such as methyl mercury
TOC Total Organic Carbon
TRS Total Reduced Sulfur
TÜV German: Technischer Überwachungsverein (Technical Inspection Association)
U.S. EPA United States Environmental Protection Agency
UV Ultraviolet, part of optical spectrum
µg/m3 Microgram per cubic metre
VOC Volatile Organic Compounds
WHO World Health Organization