Environmental Monitoring Parameters

Total suspended particulate mass concentration across all measured sizes.

Also: TSP · total suspended particulates · total dust · aerosol mass concentration

Fine particulate matter ≤2.5 µm that penetrates deep into the lungs and can enter the bloodstream. A primary ambient…

Also: fine particulate matter · fine dust · particulate matter 2.5

Inhalable ('thoracic') particulate ≤10 µm; includes coarse dust that deposits in the upper airways.

Also: coarse particulate matter · inhalable dust · particulate matter 10

Fine particulate matter ≤1 µm aerodynamic diameter, the finest fraction, which reaches the deep alveolar regions of the…

Also: submicron particles

Respirable particulate ≤4 µm (respirable convention); the fraction reaching the gas-exchange region, used in…

Also: respirable dust · respirable fraction

Sample flow is the rate at which an instrument draws air through its inlet, and on this platform it is an instrument's…

Also: air flow · sample flow rate

Airborne particle number concentration counted in discrete size bins (e.g. 0.3–10 µm); used for cleanrooms and aerosol…

Also: particle counter · particle number concentration · airborne particle counting

Respirable crystalline silica (RCS); a carcinogenic dust fraction with strict occupational exposure limits.

Also: RCS · quartz dust · crystalline silica · respirable silica

Black carbon (soot) from combustion, measured by 880 nm optical absorption. A climate forcer and a marker of traffic…

Also: BC · elemental carbon · aethalometer · aae wb

Carbon dioxide: an indicator of ventilation and indoor air quality, and an asphyxiant at high concentration.

Also: CO2 level · CO2 concentration

Total volatile organic compounds: a broadband, PID-based indicator of solvent and fuel vapors.

Also: volatile organic compounds · TVOC · total VOC

Hydrogen sulfide: a toxic, corrosive gas with a rotten-egg odor, common in wastewater and oil & gas.

Also: hydrogen sulphide · sewer gas

Carbon monoxide: a toxic, odorless combustion gas that binds to hemoglobin. An ambient and occupational hazard.

Also: CO gas

Methane: a combustible gas (explosion hazard, measured in %LEL) and a potent greenhouse gas.

Also: natural gas

Oxygen concentration; critical for confined-space safety (deficiency below 19.5 %, enrichment above 23.5 %).

Also: oxygen level · oxygen deficiency

Sulfur dioxide: a criteria pollutant from fossil-fuel combustion that irritates the respiratory system.

Also: sulphur dioxide

Nitric oxide: a combustion gas and a precursor to NO₂ and ozone.

Nitrogen dioxide: a criteria pollutant, respiratory irritant, and marker of traffic combustion.

Ammonia; a toxic, pungent gas from agriculture, refrigeration, and wastewater.

Also: ammonia gas

Combustible-gas concentration as a percentage of the Lower Explosive Limit, a key flammability and explosion-safety…

Also: combustible gas · explosive gas · flammable gas · lower explosive limit

Chlorine gas; a toxic oxidizing irritant.

Also: chlorine gas

Speciated volatile organics (benzene, toluene, ethylbenzene, xylenes, and chlorinated VOCs) from gas chromatography.

Also: benzene · toluene · ethylbenzene · xylene

Mercury vapor: a neurotoxic heavy-metal vapor.

Also: mercury vapor · mercury vapour

Hydrogen is a flammable gas, and continuous H₂ detection belongs to the fixed gas-detection systems used in mining and…

Ozone: a secondary photochemical pollutant and respiratory irritant, and an occupational hazard near generators.

Also: ground-level ozone

Hydrogen chloride (HCl), a corrosive acid gas from industrial processes and incineration, and a toxic respiratory…

Also: hydrochloric acid gas

Hydrogen fluoride (HF), a highly toxic and corrosive gas from aluminum smelting, glass etching, and refining.

Formaldehyde (CH₂O/HCHO), a colorless carcinogenic VOC emitted by pressed-wood products, insulation, furnishings, and…

Also: HCHO · CH2O · formaldehyde monitor

Barometric / atmospheric pressure.

Also: atmospheric pressure · air pressure · absolute air pressure · relative air pressure

Ambient air (dry-bulb) temperature.

Also: ambient temperature · dry bulb · sample temp

Relative humidity of air.

Also: RH · air moisture · sample rh

Horizontal wind speed.

Also: anemometer · wind velocity · wind gust

Horizontal wind direction (0–360°).

Also: wind vane · wind bearing · compass

Dew-point temperature; the temperature at which air becomes saturated.

Also: dewpoint temperature · sample dewpoint

Wind-chill (apparent cold) temperature.

Also: wind chill temperature

Accumulated precipitation depth.

Also: rainfall · rain gauge · storm rain · rain day

Instantaneous precipitation (rain) rate.

Also: rain rate · rainfall intensity · rainfall · peak rain intensity

Heat index / apparent temperature combining heat and humidity.

Also: feels-like temperature · apparent temperature · humidex

Wet-bulb temperature: an input for evaporative cooling and heat-stress calculations.

Also: wet bulb

Absolute humidity is the amount of water vapor actually in the air, independent of temperature; relative humidity, by…

Wet-Bulb Globe Temperature (WBGT): the standard composite index for occupational heat-stress assessment.

Also: wet bulb globe temperature · heat stress index

Detected lightning strike events.

Also: lightning detection · storm detection

Differential pressure between two spaces or across an air filter, used to verify room pressurization (cleanrooms,…

Also: DP · delta P · pressure drop · filter pressure

Water temperature.

Also: water temp

pH: the acidity or alkalinity of water.

Also: pH level · water acidity

Oxidation-reduction (redox) potential of water.

Also: oxidation-reduction potential · redox potential

Conductivity normalized to 25 °C (specific conductance).

Also: SPC · specific conductivity

Salinity derived from conductivity/temperature.

Also: salt content · PSU

Total dissolved solids.

Also: total dissolved solids

Water turbidity (light scattering by suspended particles).

Also: water clarity · NTU

Dissolved oxygen in water; a key aquatic-health metric.

Also: oxygen saturation · DO probe · do concentration · do saturation

Chlorophyll-a fluorescence, an indicator of algal biomass.

Also: chlorophyll-a · algae concentration · chlorophyll cell

Nitrate (NO₃) concentration in water, an indicator of nutrient pollution.

Also: NO3 · nitrate ion · nitrate nitrogen

Ammonium (NH4) concentration in water.

Also: NH4 · ammonia nitrogen · ammonium ion

Ammonia (NH₃) is the un-ionized, dissolved form of nitrogen in water, reported in milligrams per liter.

Also: ammonia nitrogen · un-ionized ammonia · unionized ammonia

Chloride ion concentration in water.

Also: chloride ion

Electrical conductivity of water (ion content).

Also: EC · electrical conductivity · actual conductivity · nlf conductivity

Other ion-selective-electrode measurements (fluoride, potassium, metals, etc.).

Also: ion-selective electrode · ISE · total nitrogen · potassium

Blue-green algae (cyanobacteria) pigment fluorescence (phycocyanin/phycoerythrin).

Also: cyanobacteria · phycocyanin · bga pc · bga pe

Resistivity is how strongly water resists an electric current (the inverse of conductivity), so the purer the water,…

Also: specific resistance

Total suspended solids.

Also: total suspended solids · turbidity to tss

Fluorescent/colored dissolved organic matter (fDOM/CDOM).

Also: dissolved organic matter · CDOM

Water density is the mass of water per unit volume, and it changes with the water's temperature and the salts dissolved…

Also: density of water

Dissolved carbon dioxide is the CO₂ held in solution in water.

Also: dissolved carbon dioxide

Water level / depth (pressure- or acoustic-derived).

Also: water depth · stage height · level sensor · vented depth

Water pressure, in this context, is the hydrostatic pressure exerted by a column of water above a submerged sensor,…

Also: water column · water column pressure · hydrostatic pressure

Totalized volume.

Also: totalized flow · flow total · volume 1

Volumetric flow rate (open-channel or pipe).

Also: flow meter · discharge measurement · flow 1 · flow setpoint

Differential pressure across a fuel or hydraulic filter or filter/separator vessel, flow-corrected per ATA 103 / EI…

Also: fuel filter differential pressure · filter vessel differential pressure · corrected DP · flow-corrected differential pressure

Fluid (oil/fuel) particle counts reported as ISO 4406 cleanliness codes.

Also: oil cleanliness · ISO cleanliness code · NAS 1638 class

Flow velocity.

Also: flow velocity

Sound Pressure Level, the instantaneous weighted level (A/C/Z, fast/slow/impulse).

Also: decibel level · dB meter · sound level

Equivalent continuous sound level (time-averaged energy), the core occupational-noise metric.

Also: average noise level · equivalent continuous sound level

Peak sound pressure level (C-weighted peak used for impulse-noise limits).

Also: peak noise level

Statistical / percentile level (e.g. L90 background, L10 intrusive).

Also: percentile noise level · L90 · L10

Maximum sound level over the interval.

Also: maximum noise level

Minimum sound level over the interval.

Also: minimum noise level

Average sound level (dosimeter, exchange-rate dependent).

Also: average sound level

Time-weighted average / noise dose over the work shift.

Also: noise dose · noise dosimeter reading

Sound Exposure Level (energy of an event normalized to 1 s).

Global (solar) radiation / irradiance.

Also: pyranometer · solar irradiance · global radiation · solar radiation

Photosynthetically active radiation (PAR) is the light in the band that plants and algae use for photosynthesis,…

The UV index is the standard scale for the strength of the sun's ultraviolet radiation at the ground, a single unitless…

Also: ultraviolet

Radon gas activity concentration. Radon is a radioactive indoor-air carcinogen.

Also: radon gas · radon test

Illuminance / light level.

Also: illuminance · light level · ambient light

Soil temperature.

Also: ground temperature

Soil moisture / water content.

Also: soil water content · volumetric water content

Leaf temperature (agricultural microclimate).

Also: canopy temperature

Leaf wetness (disease/irrigation indicator).

Also: leaf wetness sensor

Generic analog input channel mapped at configuration time.