Sensitive, Selective Ozone Detection for Safety and Air-quality Monitoring

Ozone (O₃) is a powerful oxidizing gas used in industrial processes while also posing health risks at low concentrations. Accurate ozone monitoring is essential for worker safety, environmental compliance, and air-quality assessment. Alphasense ozone sensors offer electrochemical solutions tailored to different sensitivity and interference requirements.

Sensor Product Overview

Portable and Fixed Instruments

• O3-AH – Ozone Sensor
  The O3-AH sensor is optimized for ozone measurement in applications where high sensitivity and fast response are required. It is commonly used in industrial safety monitors and environmental instruments.


• OX-A431 – Ozone and Oxidant Sensor
  The OX-A431 measures both ozone and nitrogen dioxide, and when paired with an NO2-A43F sensor, provides improved selectivity to ozone, reducing interference from other oxidizing gases. This makes it suitable for air-quality monitoring and controlled industrial environments.


• OX-B431 – Ozone and Oxidant Sensor
  The OX-B431 responds to both ozone and nitrogen dioxide, and when paired with NO2-B43F, offers an O₃, NO₂ and combined oxidant measurement. It is often used in air-quality applications where total oxidant levels are of interest.

Choosing the Right O₃ Sensor by Application

Industrial Safety & Ozone Generation

• O3-AH for direct ozone monitoring near generators or treatment systems.

Air-quality Monitoring

• OX-A431 for ozone-specific measurement when paired with NO2-A43F.


• OX-B431 where combined oxidant trends are acceptable or desired, or use with NO2-B43F for ozone and nitrogen dioxide specific measurements.

Key Benefits Across the O₃ Sensor Portfolio

• High sensitivity at low ppb/ppm levels
• Options for ozone-specific or oxidant-responsive measurement
• Compact formats for portable and fixed systems

Why OEMs Choose Alphasense?

OEMs value the application-specific selectivity options and proven electrochemical performance Alphasense provides across its ozone sensor range. Common A-series and B-series formats facilitate design and integration.

How O₃ Sensors Work?

Electrochemical ozone sensors generate a current when ozone reacts at the sensing electrode. The magnitude of this current is proportional to ozone concentration.

Why Measure Ozone Gas?

Ozone monitoring protects:

• Workers exposed to ozone-based processes
• Occupants in indoor environments
• Outdoor air-quality compliance and reporting