Parameters & units

Every reading you send must use the canonical unit for its parameter, and its value must fall within the permitted range. A different unit rejects the batch (unit-mismatch); a value outside the range rejects it (value-out-of-range).

These are the built-in parameters seeded by the platform. (Operators of an instance may add extension parameters with their own canonical unit and range; ask your platform administrator if you need one that isn't listed.)

Parameter code	Quantity	Canonical unit	Permitted range
`co2`	Carbon dioxide	`ppm`	0 – 50 000
`eco2`	Equivalent CO₂	`ppm`	0 – 65 000
`co`	Carbon monoxide	`ppm`	0 – 2 000
`o3`	Ozone	`µg/m³`	0 – 500
`no2`	Nitrogen dioxide	`µg/m³`	0 – 500
`so2`	Sulphur dioxide	`µg/m³`	0 – 500
`voc`	Volatile organic compounds	`ppb`	0 – 60 000
`pm1`	Particulate matter ≤ 1 µm	`µg/m³`	0 – 500
`pm2_5`	Particulate matter ≤ 2.5 µm	`µg/m³`	0 – 500
`pm4`	Particulate matter ≤ 4 µm	`µg/m³`	0 – 1 000
`pm10`	Particulate matter ≤ 10 µm	`µg/m³`	0 – 1 000
`temperature`	Air temperature	`°C`	−40 – 85
`humidity`	Relative humidity	`%`	0 – 100
`air_velocity`	Air velocity	`m/s`	0 – 10
`pressure`	Atmospheric pressure	`Pa`	85 000 – 110 000
`illuminance`	Illuminance	`lx`	0 – 100 000
`cct`	Correlated colour temperature	`K`	1 000 – 20 000
`laeq`	A-weighted equivalent sound level	`dB(A)`	0 – 140

Notes

The unit string must match exactly, including the casing and the symbols (µg/m³, dB(A), °C). Send the unit string from the table verbatim.
A sensor may only report parameters it declared at registration. Declaring co2 and temperature, then sending humidity, rejects the batch (parameter-not-declared) — add the parameter to the sensor first.
Ranges are inclusive sanity bounds, not calibration limits. They exist to catch obviously broken readings (a stuck probe, a wrong unit), not to grade air quality.

The authoritative, machine-readable list for a running instance is the ieq.parameter_ranges table; the table above is the seeded default.

Ambiquality Wiki

Parameters & units

Notes