Bosch Sensortec | BME680 Datasheet

9 | 53

Modifications reserved |Data subject not change without notice | Printed in Germany

Document number: BST-BME680-DS001-09 Revision_1.9_022024

Table 3: IAQ system parameter specification3

Parameter

Symbol

Condition

Min

Typ

Max

Unit

Accuracy status4

AXIAQ

Android compatible

0

3

IAQ Resolution

IAQrs

1

IAQ Range

IAQrg

0

500

Sensor-to-sensor

deviation5

IAQS2S

All operation modes

±15%

±15

Durability to

siloxanes6,7,8

IAQS2S

Sensor-to-sensor deviation

±15%

±15

IAQdrift

Drift at low & high

concentrations

±1%

±4

Table 4: Index for Air Quality (IAQ) classification and color-coding9

IAQ Index

Air Quality

Impact (long-term exposure)

Suggested action

0 – 50

Excellent

Pure air; best for well-being

No measures needed

51 – 100

Good

No irritation or impact on well-being

No measures needed

101 – 150

Lightly polluted

Reduction of well-being possible

Ventilation suggested

151 – 200

Moderately polluted

More significant irritation possible

Increase ventilation with clean air

201 – 250

Heavily polluted

Exposition might lead to effects like

headache depending on type of VOCs

optimize ventilation

251 – 350

Severely polluted

More severe health issue possible if

harmful VOC present

Contamination should be

identified if level is reached even

w/o presence of people; maximize

ventilation & reduce attendance

> 351

Extremely polluted

Headaches, additional neurotoxic effects

possible

Contamination needs to be

identified; avoid presence in room

and maximize ventilation

3 IAQ parameters only apply for the combination of BME680 together with the Bosch Software Environmental Cluster (BSEC) solution (available separately, see Chapter 4)

4 The accuracy status is equal to zero during the power-on stabilization times of the sensor and is equal to 3 when the sensor achieves best performance

5 Tested with 0.6–90 ppm of EtOH at 5–40 °C, 20–80% r.H. and atmospheric pressure. Condition is valid after the calibration period of the BSEC algorithm.

6 Siloxanes are present in a typical indoor environment and can in principle perturb the metal-oxide-based gas sensor performance.

7 220 hours of 700 mg/m3 of octamethylcyclotetrasiloxane (D4) in ambient conditions (i.e. 20 °C and 50% r.H.) simulates the amount of siloxanes in a typical indoor environment over more

than 10 years.

8 Tested with 0.5–15 ppm of b-VOC at 20 °C and 50% r.H. using continuous operation mode for 220 hours of 700 mg/m3 of octamethylcyclotetrasiloxane (D4).

9 According to the guidelines issued by the German Federal Environmental Agency, exceeding 25 mg/m3 of total VOC leads to headaches and further neurotoxic impact on health. The BSEC

software auto-calibrates the low and high concentrations applied during testing to IAQ of 50 and 200, respectively.