Measurement method
Mass spectrometry
Also: MS, GC-MS, gas chromatography mass spectrometry, PTR-MS, mass spectrum analysis
An analytical method that ionises molecules and sorts the ions by mass, giving each compound a pattern that identifies it. Coupled to a separation step, it is what turns a sample of indoor air into a list of named compounds with concentrations.
What it is
Identification is what separates this method from every sensor in this vocabulary. A sensor reports that something is present; mass spectrometry reports what. That is the difference between a total volatile organic compound figure and a table naming benzene, toluene, limonene and their concentrations.
In practice it works in two modes. Offline, air is collected first — onto a sorbent tube or a passive sampler — then separated by gas chromatography and identified compound by compound; this is the reference approach behind most published indoor measurements, and its time resolution is the sampling period, typically hours to days. Online, air is drawn straight into the instrument and analysed continuously, which resolves events in seconds and shows a cooking peak or a cleaning peak as it happens.
Its cost and its need for an operator are why it stays in studies rather than in homes, and why sensor readings are calibrated against it.
What the studies report
| Linked to | Effect | Population | Study design | Source | Checked |
|---|---|---|---|---|---|
| Volatile organic compounds (VOCs) | emission-rate 6.3 | — · university classroom | measurement campaign in an occupied university classroom: time-resolved concentrations of volatile organic compounds in room air and in supply air measured continuously with a proton-transfer-reaction time-of-flight mass spectrometer during occupied and unoccupied periods, with the emission factor of each human-emitted compound obtained by dividing the occupant-associated source rate by the occupancy | F-1575 Volatile organic compound emissions from humans indoors (2016) | machine |
| Volatile organic compounds (VOCs) | ratio 9 | — · laboratory (air drawn over the screen) | laboratory study of liquid crystal display screens as a source of indoor air constituents: air passing over the screens of a smartphone, a computer monitor, a used laptop and a television analysed with a proton-transfer-reaction time-of-flight mass spectrometer, with the humidity of the air varied | F-1579 Liquid crystal display screens as a source for indoor volati… | machine |
| Volatile organic compounds (VOCs) | the compounds compared are carbon dioxide, acetone and isoprene; for acetaldehyde the study found the emission rates equivalent | — · cinema auditorium | measurement campaign in a cinema: volatile organic compounds emitted by seated audiences measured at high frequency with a proton-transfer-reaction time-of-flight mass spectrometer across multiple screenings of three films in a room flushed at a known rate, so that emission rates could be calculated for adults and for children | F-1585 Real world volatile organic compound emission rates from sea… | machine |
| Volatile organic compounds (VOCs) | other 20 | — · home | field measurement campaign in homes affected by a wildland-urban interface fire: volatile organic compounds measured indoors by proton-transfer-reaction time-of-flight mass spectrometry over the weeks following the fire, with mitigation tests using activated-carbon air cleaners and window opening | F-1586 Volatile Organic Compounds Inside Homes Impacted by Smoke fr… (2025) | machine |
| Particulate matter (PM₂.₅ and PM₁₀) | other 29 | — · classroom | measurement study in a university classroom with no modern history of smoking: submicrometre aerosol measured by aerosol mass spectrometry indoors and outdoors, with the organic fraction resolved into components by factor analysis | F-1761 Thirdhand smoke uptake to aerosol particles in the indoor en… (2018) | machine |
Each row is one Finding — a sentence as printed in one study, recorded with its page in the Coridum Knowledge Base. Follow the Finding number for the exact wording and the citation. Checked says who verified the row: machine means every automatic check passed and the surrounding text was read; person means someone read the sentence in the document. Rows are re-checked by a person over time. The studies are curated in the Coridum Knowledge Base; the reading of them together is a Claim, shown separately.
Identifiers
- MeSH
- D013058
Cite this page
Coridum Research. Mass spectrometry. Coridum Knowledge G-0160, 16 September 2026. https://coridum.com/k/G-0160/