ATEX	Atmosphères Explosibles
BAL	Balance
bara	Absolute bar
CMOS	Complementary Metal–Oxide–Semiconductor
DPSS	Diode-Pumped Solid-State
FTIR	Fourier Transform Infrared
GC	Gas Chromatography
HHV	Higher Heating Value
HNG	Hydrogen-Enriched Natural Gas
ISO	International Organization for Standardization
LNG	Liquefied Natural Gas
LOD	Limit of Detection
MEMS	Micro-Electro-Mechanical Systems
NG	Natural Gas
OIML	International Organization of Legal Metrology
TCD	Thermal Conductivity Detector
TDLAS	Tunable Diode Laser Absorption Spectroscopy
TEC	Thermo-Electric Cooler