VOC monitoring and product labeling use specific terminology that isn’t always explained. This glossary covers the terms you’re most likely to encounter.
- TVOC measures combined VOC concentration; ppb and mg/m³ are common units for specific readings.
- Low-VOC/No-VOC labeling claims can vary by manufacturer without independent verification.
- GREENGUARD certification provides third-party verification of low-emission claims.
- A ‘flush-out’ is a deliberate ventilation practice to accelerate VOC reduction after new material installation.
Measurement Terms
TVOC (Total Volatile Organic Compounds): a combined measurement of many VOC types together, commonly displayed on consumer air quality monitors. ppb (parts per billion): the common unit for individual compound concentrations like formaldehyde. mg/m³: an alternative concentration unit sometimes used for TVOC.
Product Labeling Terms
Low-VOC and No-VOC: labeling claims on paint and other products indicating reduced or minimal VOC content, though specific thresholds for these claims can vary by manufacturer and aren’t always independently verified. GREENGUARD Certified: a third-party certification program indicating a product has been tested and meets specific low-emission standards.
Process Terms
Off-gassing: the release of VOCs from a material over time, typically highest shortly after manufacture or installation and declining afterward. Flush-out: a ventilation practice (running increased fresh-air exchange) specifically intended to accelerate VOC reduction after new material installation.
Terms That Describe How a Sample Was Taken
Grab sample: a single sample collected at one moment, which describes conditions at that moment only. Passive or integrated sample: a badge or tube left in place for a stated period, which reports an average across that period rather than a peak. Continuous monitoring: a logging device that records a trend over time. A report should say which of these it used, because the same room can produce very different impressions depending on the method and the timing.
Detection limit: the lowest amount the method used could reliably identify. Below detection limit, sometimes shown as non-detect, means the method could not see it, which is not the same statement as absent. Blank and duplicate: quality-control samples used to check that the sampling and laboratory process itself is behaving, and their presence in a report is a sign of a controlled method rather than padding.
Terms That Describe a Reference Value
Guideline, reference concentration, screening level and action level are not interchangeable, and reports sometimes use them loosely. Some are health-based values derived by a public health body, some are practical thresholds chosen to trigger a next step, and each is tied to a particular averaging time. A value meant to be averaged over a long period says something different from one meant to describe a brief peak.
The practical consequence is that a number quoted without its averaging time and without the body that issued it cannot really be interpreted. If a report compares your result against a reference value, ask which value, from which organization, and over what averaging period, and check that the sampling method actually produced a result on that same basis.
FAQ
Is a ‘low-VOC’ label always independently verified?
Not always — look for third-party certifications like GREENGUARD for more verified assurance, since manufacturer self-labeling standards can vary.
My report says below detection limit. Does that mean zero?
No. It means the method used could not detect the substance at its sensitivity, which depends on the sampling method and how long the sample ran. A more sensitive method or a longer sampling period can return a result where a shorter one did not.
Why do two monitors give different combined readings in the same room?
The combined index is not a single standardized quantity. Different sensors respond to different mixes of compounds and are calibrated against different reference gases, so treat a consumer reading as a relative trend on that device rather than an absolute value comparable across devices.
This glossary is for general orientation — refer to your specific monitor’s documentation or product certification details for terms not covered here.
These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Content is for informational purposes only and is not medical advice; consult a qualified healthcare provider before starting any supplement. As an Amazon Associate we earn from qualifying purchases.
