O3 sensor
Ozone
Reliable real-time
data on O3
GasPlug TECHNOLOGY | PATENTED DESIGN
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 are originated 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’s 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 accurately the O3 concentration, it is required to install in the same device the NO2 cartridge.
The Kunak algorithm considers both concentrations allowing for accurate O3 measurements with, with no NO2 influence, even at high temperatures which are related to higher O3 concentration due to the 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 45ºC
Operating RH range(4)
10 to 99 %RH
Recommended RH range(4)
15 to 85 %RH
Operating life(5)
> 24 months
Guarantee range(6)
20 ppm
Limit of Detection (LOD)(7)
3 ppb
Repeatability(8)
4 ppb
Response time(9)
< 70 sec
Typical accuracy (MAE)(10)
± 8 ppb
Typical precision R2(10)
> 0.9
Typical slope(10)
0.85 - 1.18
Typical intercept (a)(10)
-3 ppb ≤ a ≤ +3 ppb
DQO - Typical U(exp)(11)
< 20%
Typical Intra-model variability(12)
< 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 PM sensor Type A: -40 to 50ºC 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 20ºC and 50% RH. The limit of detection is the minimum concentration that can be detected as significantly different at zero gas concentration, calculated according to the Technical Specification CEN/TS 17660.
- Repeatability: measured at laboratory conditions at 20ºC and 50% RH. Closeness of the agreement between the results of successive measurements of the same measure 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: statistics obtained between the device hourly measurements and reference instruments in field test between -10 to +30ºC at different locations. (*) For the type B PM sensor, the expected error for PM10 is higher in presence of coarse particles.
- Typical accuracy: for criteria pollutants is the average Mean Absolute Error (MAE) obtained between the device hourly measurements and reference instruments for 1 to 8 months field test between -10 to +30ºC in different countries. For other pollutants is the expected error of the measurement at the reading.
- DQO-Typical U(exp): Data Quality Objetive expresed as the Expanded Uncertainity in the Limit Value obtained between the device hourly measurements and reference instruments for 1 to 8 months field test between -10 to +30ºC in different countries, calculated according to the European Air Quality Directive 2024/2881 and from the Technical Specification CEN/TS 17660. (*) For the type B PM sensor, the expected error for PM10 is higher in presence of coarse particles.
- Typical intra-model variability: calculated as the standard deviation of the three sensor means in 1 to 8 months field test between -10 to +30ºC 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.
