ICAD NO₂–NOx–NO Analyzer Series 210
The ICAD Series 210 provides precise and fast in‑situ measurements of NO and NO₂ using patented Iterative Cavity DOAS spectroscopy. It directly detects NO₂ — without converter artefacts and without humidity interferences — and operates without the need for NO₂ calibration gas.
ICAD instruments offer very low noise, negligible zero drift and a wide dynamic range. This makes them suitable for both highly polluted roadside environments and ultra‑clean background locations. Thanks to low power demand and robust housings, ICAD systems can be used in stationary installations, industrial stacks, mobile vehicle platforms, ships and UAV‑based deployments.
Models equipped with integrated CO₂ sensors (DE versions) support real‑time plume chasing and NOx emission‑factor calculations for on‑road and off‑road applications.
Operation Principle
The ICAD analyzer uses a closed‑path optical resonator to achieve very long effective absorption paths. This enables highly sensitive detection of NO₂ based on its characteristic absorption features in the 430–480 nm wavelength range.
NO is measured via an internal ozone‑based, NOx‑free converter that converts NO to NO₂. Two parallel measurement cells — one for direct NO₂ and one for NO after conversion — ensure precise and drift‑free NO, NO₂ and total NOx quantification. The method is insensitive to humidity and requires no sample drying.
Document Downloads
All key ICAD documents grouped by category for quick access.
Product Overview
Application Notes
Additional Information
Key Applications & Advantages
Air‑quality monitoring
Provides accurate NO₂ and NOx data for roadside stations, urban background locations and long‑term environmental monitoring.
Industrial emission control
Measures NOx from engines, combustion systems and industrial stacks without converter drift or cross‑sensitivities.
Mobile field measurements
Fast 1–3 s response enables vehicle plume chasing, ship‑emission studies and flexible outdoor deployment.
Background & research studies
L and DL versions achieve ppt‑level sensitivity for atmospheric chemistry and clean‑air measurements.
Calibration‑free operation
No NO₂ calibration gas required thanks to spectroscopic reference data and automatic zero checks.
Robust optical design
Temperature‑stabilised, vibration‑resistant optics ensure stable operation — no drying of sample air needed.
Mobile & rugged housings
IP64 M‑versions support outdoor use, vehicle installations and ship‑based measurements.
Emission‑factor analysis
DE models include CO₂ measurement for on‑road plume chasing and NOx emission‑factor calculation.
ICAD Model Comparison
| Model | Detected species | Typical detection limit | Main features |
|---|---|---|---|
| ICAD‑NO₂‑210 | NO₂ | ~0.09 ppb @ 60 s | Direct NO₂ monitoring for air‑quality stations and industrial applications. |
| ICAD‑NOx‑210D | NO + NO₂ → NOx | ~0.09 ppb @ 60 s (NO₂) | Dual‑cell NOx analyzer with internal ozone converter for NO to NO₂ conversion. |
| ICAD‑NOx‑210DE | NO + NO₂ + CO₂ | ~0.09 ppb @ 60 s (NO₂) | Same as 210D, plus CO₂ measurement for emission‑factor and plume‑chasing studies. |
| ICAD‑NO₂‑210L | NO₂ | 15–50 ppt | High‑grade NO₂ analyzer for research and low‑background applications. |
| ICAD‑NOx‑210DL | NO + NO₂ → NOx | 20–50 ppt (NO₂) | Highest‑precision NOx analyzer with ultra‑low detection limits. |
| ICAD‑NOx‑210DM / DE‑M | NO + NO₂ (+ CO₂, depending on model) | Equal to corresponding base model | Mobile IP64 housing for field, vehicle and outdoor use. |
Housing Configurations
The ICAD Series 210 is available in several housing variants to support laboratory setups, stationary monitoring and mobile field applications.
Frequently Asked Questions
How does the ICAD analyzer detect NO₂?
ICAD measures NO₂ directly using cavity‑enhanced spectroscopy in the 430–480 nm region. This avoids converter artefacts and humidity interferences.
How is NO measured?
NO is converted to NO₂ using an internal ozone‑based, NOx‑free converter. Parallel cells measure direct NO₂ and converted NO for accurate NOx.
Does the ICAD analyzer require calibration gas?
No. ICAD uses spectroscopic reference data and automatic zero checks. Only the optional NO converter may require a periodic functional check.
What are the typical detection limits?
Standard models reach sub‑ppb sensitivity. L and DL versions achieve ppt‑level precision for background and research work.
Is the instrument affected by humidity or temperature changes?
No. ICAD is insensitive to water vapour and uses temperature‑stabilised optics for long‑term stability.
Can ICAD be used for mobile measurements?
Yes. IP64 M‑versions are designed for vehicle, ship and UAV‑based field deployments.
Which ICAD model is best for my application?
NO₂‑210 for NO₂ only, NOx‑210D for standard NOx, NOx‑210DE for NOx+CO₂ emission studies, and L/DL versions for high‑sensitivity research applications.
ICAD Model Recommendation Matrix
Quick visual guide to help identify the most suitable ICAD 210 model for your measurement needs.
| Model | Direct NO₂ | NOx (NO+NO₂) | CO₂ | High Sensitivity (ppt‑level) |
Mobile / IP64 | Typical Application |
|---|---|---|---|---|---|---|
| ICAD‑NO₂‑210 | ✔ | – | – | – | – | Standard NO₂ monitoring (air quality, industry) |
| ICAD‑NOx‑210D | ✔ | ✔ | – | – | – | General NOx measurement (stationary & mobile) |
| ICAD‑NOx‑210DE | ✔ | ✔ | ✔ | – | – | Plume chasing, emission factors, vehicle studies |
| ICAD‑NO₂‑210L | ✔ | – | – | ✔ | – | Research-grade NO₂ for background/ppt levels |
| ICAD‑NOx‑210DL | ✔ | ✔ | – | ✔ | – | High-precision NOx research, test benches |
| M‑Versions (DM / DE‑M) | ✔ | ✔ | depending on model |
same as base model |
✔ | Mobile/IP64 field use, vehicles, ships, outdoor |
Need help selecting the best model?
Contact our team — we’re happy to advise.
Airyx works with trusted distributors worldwide to provide local support for open‑path DOAS, MAX‑DOAS and air‑quality monitoring solutions.
For direct inquiries, please use the contact form below.
The map below shows the regions currently supported by our international distributor network.
EUROPE
FRANCE:
MEGATEC SAS
Immeuble Homère, Les Algorithmes
91190 Saint-Aubin, France
Phone: + 33 1 69 35 58 00
Website: https://www.megatec.fr/
Contact: https://www.megatec.fr/contact
Contact person: Fabrice Losbar
SLOVAKIA, CZECH & LITHUANIA:
ENVItech Bohemia s.r.o.
Ovocná 34
161 00 Praha 6
Czech Republic
Webite: ENVItech Bohemia s.r.o.
Contact: Contact
SPAIN & PORTUGAL:
GREEN LIGHT RESEARCH SLU
Airyx products at Green Light Research:
ICAD NOx analysators
ICAD HONO/NO2 anaylsator
Open Path remote sensing
SkySpec remote sensing
ITALY:
LUCHSINGER SRL
Website: http://www.luchsinger.it/
Airyx Products | Luchsinger
UNITED KINGDOM & IRELAND:
CURA TERRAE AIR LTD
(FORMERLY ENVIRO TECHNOLOGY SERVICES LTD)
Unit B1, Kingfisher Business Park, London Road,
Stroud, Gloucestershire, GL5 2BY, UK
Phone: +44 (0) 1453 733200
Website: www.et.co.uk
NO₂/NOx/NO Analyser High Grade Version (ICAD 200DL) | ET
AirYX Plume Chasing - NO2 / NOX / NO ICAD In Situ Monitor | ET
AirYX HONO / NO2 Analyser (Model ICAD 200L) | Enviro Technology Services (et.co.uk)
NETHERLANDS, BELGIUM, LUXEMBOURG, DENMARK, SWEDEN, NORWAY:
THE DUTCH SCIENTIST
Kardinaal van Rossumplein 11
5211 RV ‘s-Hertogenbosch
The Netherlands
Phone: +31 629 437 116
Website: www.thedutchscientist.com
FINLAND:
HNU NORDION
Atomitie 5 B 600371, HELSINKI, FINLAND
Phone: +40 745 6225
Website: https://hnunordion.fi/
GREECE:
Polaris Environment Ltd
Complete Environmental Solutions
44 Lagoumitzi Str, 11745 Athens, Greece
Attn. Grigoris Nikolidakis
Phone: +306975906253
Website: www.polaris-environment.gr
ROMANIA (ICAD only):
APEL LASER
Mogosoaia, Strada Vanatorilor nr. 25, cod 077135, jud. Ilfov, Romania
Phone: +40 21 31 70 910
Website: Apel Laser » Lighting the Future
ROMANIA (Open Path, SkySpec, WGA):
PHANOS
Bucharest-Ploiesti Road 17, 7th floor, Bucharest, 013682, Romania
Website: Apel Laser » Lighting the Future
Contact
BULGARIA, SERBIA, NORTH MACEDONIA, ALBANIA, MONTENEGRO, SLOVENIA, CROATIA, TURKEY:
STABO-Tech. Ltd.
ul. Dimitar Naumov, 88
6000 Stara Zagora, Bulgaria
Phone: 0039 349 5440483
Website: http://stabo-tech.eu/
ASIA
INDIA:
M&G analyser systems
501,Zenith commercial complex
28/2 Near Agricultural college.
Shivaji Nagar, Pune -411007, India
Website:
:: M & G Analyser Systems | Pune ::
Contact:
:: M & G Analyser Systems | Pune ::
Phone: +91 9822667465.
Kind Attn: Hemanth Krishna Martha,
VIETNAM:
REECO Science and Technology Co., Ltd.
Building A, Software Technology Park, Vo Truong Toan Street,
Vietnam National University, Quarter 6, Linh Trung Ward, Thu Duc City,
Ho Chi Minh City, Vietnam
Website:
Air quality monitoring equipment - Reeco (reecotech.com.vn)
Contact:
INDONESIA:
PT JJExotranoz Inter Vania
Jln. Raya Boulevard Q1 no. 5, Cibubur, Indonesia
Contact: Jefry KP
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CHINA:
LICA United Technology Limited
The 5th.Building,No.18,Anningzhuang East Road
Haidian District, 100085, Beijing, China.
Website: LICA United Technology Limited (li-ca.com)
Airyx Products:
ICAD NO2 / NOx / NO Analyzer - Trace gas measurement
ICAD NO2 / NOx / NO分析仪 - 痕量气体测量 - 北京理加联合科技有限公司 (li-ca.com)
REPUBLIC OF KOREA:
Aireet Inc.
105-502 (5F), 16, Gakhwa-daero 69beon-gil, Buk-gu
Gwangju, Republic of Korea
Phone: +82 (0)10-9350-8148
Website: www.aireet.co.kr
Contact Person: Joonwoo Kim
RUSSIA AND CIS - (ARMENIA, AZERBAIJAN, BELARUS, KAZAKHSTAN, KYRGYZTAN, MOLDOVA, TAJIKISTAN, AND UZBEKISTAN):
Eniseylab Ltd
Russia, 660025, Krasnojarsk, Shelkovaya, 10, Room 102
Phone: +7 (391) 271-66-50
Contact Person: Dmitriy Zhiltsov
Website: www.eniseylab.ru


























