Glossary
The vocabulary of indoor air, defined once so the rest of the site can stay readable.
A
- Acrolein
- A colorless to pale-yellow liquid with a strong, pungent odor, used as a biocide to control plants, algae, molluscs, fungi, rodents and microorganisms.
- Acute (short-term) toxicity
- Effects resulting from single or repeated exposures over a day — headaches, nausea, irritation of the eyes, throat and nose, dizziness and asthma.
- Anthropogenic emissions
- Atmospheric emissions of pollutants that originate from human activities.
- Anthropogenic VOCs
- Volatile organic compounds emitted by human activities, for example oil-derived solvents.
- Antimicrobials
- Substances that kill or inhibit microorganisms; triclosan is a common example found in consumer products.
B
- Biogenic VOCs
- Volatile organic compounds emitted naturally, for example terpenes released by plants and wood.
C
- Cardiovascular disease (CVD)
- Conditions affecting the heart and blood vessels; long-term exposure to particulate matter is among the environmental factors studied in relation to it.
- Chronic (long-term) toxicity
- Effects resulting from long-term exposure, including damage to the central nervous system, the kidneys or the liver.
- Chronic obstructive pulmonary disease (COPD)
- A long-term lung condition characterised by persistently obstructed airflow; indoor air quality is one of the environmental factors relevant to it.
- Continuous and constant sources
- Sources that generate uniform emissions over time — linoleum, cork, wood finishes, or furniture emitting formaldehyde.
D
- Diagnostic spirometer
- A device measuring the volume and speed of air a person can inhale and exhale, used to assess lung function.
- DIRECTIVE 2004/42/CE
- EU directive of the European Parliament and of the Council limiting emissions of volatile organic compounds due to the use of organic solvents in paints and varnishes.
E
- Electrochemical gas sensors
- Sensors that detect gases through a chemical reaction producing an electrical signal. They feature low power consumption, quick response time, high sensitivity and a longer lifespan.
- Electronic nicotine devices (ENDs)
- Battery-powered devices that deliver nicotine by heating a liquid into an aerosol; a source of indoor airborne constituents.
- Emission
- The release of a substance from a point or diffuse source into the atmosphere.
- Environmental Protection Agency (EPA)
- The United States federal agency responsible for environmental protection, and a widely referenced source of indoor air quality guidance.
- European Chemicals Agency (ECHA)
- The EU agency managing the technical and administrative aspects of chemicals regulation, including REACH.
H
- Harmful and potentially harmful constituents (HPHCs)
- Chemicals or chemical compounds in tobacco products and their smoke or aerosol that cause or may cause harm.
- Hazardous air pollutants (HAPs)
- Air pollutants known or suspected to cause cancer or other serious health effects.
- Humidity
- The amount of water vapour present in air. Indoors it is usually expressed as relative humidity — a percentage of the maximum the air can hold at that temperature.
I
- International Agency for Research on Cancer (IARC)
- The World Health Organization agency that evaluates and classifies the carcinogenicity of substances and exposures.
M
- Measuring Instrument Directive (MID) 2004/22/EC
- EU directive harmonising the requirements placed on measuring instruments placed on the market.
- Metal oxide sensors
- Gas sensors whose semiconducting metal-oxide layer changes electrical resistance in the presence of target gases.
- Micron
- A micrometre — one millionth of a metre. The unit in which particulate matter sizes are expressed.
N
- Non-dispersive infrared (NDIR) method
- A measurement technique that determines gas concentration — carbon dioxide above all — from the absorption of infrared light.
- Non-methane volatile organic compounds (NMVOCs)
- Organic compounds other than methane that produce photochemical oxidants by reacting with nitrogen oxides under solar radiation.
- Normal temperature and pressure
- Reference conditions of 25 °C and 101.3 kPa, used so that measurements from different places remain comparable.
O
- Obstructive lung disease
- A group of conditions in which airflow out of the lungs is obstructed, asthma and COPD among them.
- Organic compounds associated with particulate matter (POM)
- Organic compounds with a boiling point above 380 °C, which are therefore carried on particles rather than as free gas.
- Organohalogen and organophosphorus compounds
- Two families of compounds commonly used as flame retardants in furnishings and electronics.
- Ozone precursors
- Substances that lead to ozone formation: nitrogen oxides, non-methane volatile organic compounds, methane and carbon monoxide.
P
- Passive infrared (PIR)
- A sensing method that detects movement from changes in infrared radiation, commonly used for occupancy detection.
R
- Recurring intermittent source
- A source that emits repeatedly but not continuously — cooking, for example. Room fragrances are an occasional intermittent source.
S
- Semi-volatile organic compounds (SVOC)
- Organic compounds with boiling points from 240–260 °C up to 380–400 °C.
- Suspended particulate matter (SPM)
- Solid and liquid particles small enough to remain suspended in air rather than settling out.
T
- Total suspended particles (TSP)
- The total mass of all airborne particles in a sample, regardless of size.
U
- Ultrafine particles (UP)
- Particles smaller than 0.1 micrometre. Their small size lets them travel deepest into the respiratory system.
V
- Very volatile organic compounds (VVOCs)
- Organic compounds with boiling points from below 0 °C up to 50–100 °C.
- Volatile organic compounds (VOC)
- Organic compounds with boiling points from 50–100 °C up to 240–260 °C.