* Download datasheet *
* O3 Co-location field study *
Where is it found?
Ozone (O3) is found in the troposphere and it is the result of the atmospheric reaction of a number of precursor pollutants, which come from both natural and man-made sources. Precursor pollutants originate from human activities and include hydrocarbons and nitrogen oxides.
They are largely emitted by cars and other vehicles, fossil fuel power plants, oil refineries, the agriculture sector and a number of other industries.
Why is it harmful?
Ozone (O3) is a reactive gas that exists in two layers of the atmosphere: the stratosphere (upper layer) and the troposphere (at ground level and up to 15 km). Ozone, in the upper layer, is essential to protect the Earth from the sun's ultraviolet rays.
At lower levels, it is an important greenhouse gas and an air pollutant, which is harmful to human and ecosystem health. It is also the major component of urban smog.
O3 cartridge
The ozone cartridge has a built-in electrochemical sensor responsive to NO2 and O3 concentrations. Hence, in order to measure the O3 concentration accurately, it is required to install the NO2 cartridge in the same device.
The Kunak algorithm considers both concentrations, allowing for accurate O3 measurements with no NO2 influence, even at high temperatures, which are related to higher O3 concentrations due to solar radiation.
Technical specifications
| Type | Electrochemical |
| Unit of measurement | µg/m3, ppb |
| Measurement range (1) | 0–2,000 ppb |
| Resolution (2) | 1 ppb |
| Operating temperature range (3) | -30 to 50 °C |
| Operating RH range (4) | 10 to 99 %RH |
| Recommended temp. & RH range (5) |
-30 to 45 °C 15 to 85 %RH |
| Operating life (6) | > 24 months |
| Guarantee range (7) | 20 ppm |
| Limit of Detection (LOD) (8) | 3 ppb |
| Repeatability (9) | 4 ppb |
| Response time (10) | < 70 sec |
| Typical accuracy (12) | ± 8 ppb |
| Typical precision R2 (11) | > 0.9 |
| Typical slope (11) | 0.85–1.18 |
| Typical intercept (a) (11) | -3 ppb ≤ a ≤ +3 ppb |
| DQO - Typical U(exp) (13) | < 20% |
| Typical intra-model variability (14) | < 1 ppb |
- Measurement range: Concentration range measured by the sensor.
- Resolution: Smallest unit of measurement that can be indicated by the sensor.
- Operating temperature range: Temperature interval at which the sensor is rated to operate safely and provide measurements. In the PM sensor Type A: -40 to 50 °C with heater (more information on this version on request).
- Operating RH range: Humidity interval at which the sensor is rated to operate safely and provide measurements.
- Recommended RH range: Recommended relative humidity range for optimal sensor performance. Continuous exposure outside the recommended range may damage the cartridge.
- Operating life: Time period during which the sensor can operate effectively and accurately under normal conditions.
- Guarantee range: Concentration range covered by Kunak's guarantee.
- LOD (Limit of Detection): Measured at laboratory conditions at 20 °C and 50% RH. The limit of detection is the minimum concentration that can be detected as significantly different to zero gas concentration, calculated according to the Technical Specification CEN/TS 17660.
- Repeatability: Measured at laboratory conditions at 20 °C and 50% RH. Closeness of the agreement between the results of successive measurements of the same measurand carried out under the same conditions of measurement, calculated according to the Technical Specification CEN/TS 17660.
- Response time: Time needed by the sensor to reach 90% of the final stable value.
- Typical precision – R2, slope and intercept: Statistics obtained between the device hourly measurements and reference instruments in field tests between -10 to +30 °C at different locations. For the type B PM sensor, the expected error for PM10 is higher in the presence of coarse particles.
- Typical accuracy: For criteria pollutants, this is the average Mean Absolute Error (MAE) obtained between the device hourly measurements and reference instruments for 1 to 8 months of field tests between -10 to +30 °C in different countries. For other pollutants, it is the expected error of the measurement at the reading.
- DQO - Typical U(exp): Data Quality Objective expressed as the Expanded Uncertainty in the Limit Value obtained between the device hourly measurements and reference instruments for 1 to 8 months of field tests between -10 to +30 °C in different countries, calculated according to the European Air Quality Directive 2024/2881 and the Technical Specification CEN/TS 17660. For the type B PM sensor, the expected error for PM10 is higher in the presence of coarse particles.
- Typical intra-model variability: Calculated as the standard deviation of the three sensor means in 1 to 8 months of field tests between -10 to +30 °C in different countries.
A, B, C, D superindex: The super indexes refer to different types of cartridges related to the same target pollutant but with different technical specifications.
