Hydrogen Chloride Monitoring for Semiconductor and Process Control

Alphasense hydrogen chloride (HCl) sensors support semiconductor manufacturing, industrial cleaning, stack emissions and emergency response applications. A- and B-Series sensors are available in analogue and IST variants to suit portable analyzers and fixed gas detection systems.


Sensor Product Overview


  • Portable & Spot-Check – A-Series HCl Sensors

  • HCL-A1 – A-Series HCl sensors for handheld instruments and portable monitors (0–100 ppm).

  • Fixed & High-Humidity – B-Series HCl Sensors

  • HCL-B1 – B-Series sensors for portable and fixed detection in high-humidity or harsh environments.

  • Digital “+” Integrated Smart Technology (IST) Variants

  • HCL-A1-IST | HCL-B1-IST add on-sensor memory and temperature measurement for plug-and-play integration and simplified temperature compensation.

Choosing the Right Sensor by Application


  • Semiconductor & Industrial Cleaning

  • HCL-A1 – Portable analyzers used for leak tracing and maintenance.
  • HCL-B1 – Fixed monitoring in etch, cleaning, and exhaust systems where humidity and corrosive conditions are present.

  • Stack Emissions & Process Control

  • HCL-B1 – Suitable for stack and process monitoring where robustness and stable baselines are essential.

  • Emergency Response & Fire Safety

  • HCL-A1 | HCL-B1 – Portable and fixed systems used in emergency response and post-incident assessment

Key Benefits Across the Sensor Portfolio


  • PPM-range HCl monitoring tailored for industrial safety and emissions applications.
  • A / B-Series formats for both portable and fixed system architectures.
  • IST “+” variants add temperature sensing and on-board calibration data for plug-and-playfield serviceability.

Why OEMs Choose Alphasense?


  • Proven performance of HCl sensors in high-humidity and corrosive environments, supported by temperature and zero-drift characterization.
  • Unified accessory ecosystem (gas hoods, ISBs, AFEs) across toxic gas families.

How HCl Gas Sensors Work?


HCl sensors are electrochemical amperometric devices. Hydrogen chloride reacts at the working electrode, generating a current measured by instrument electronics. B-Series designs offer larger electrolyte volumes for improved stability in harsh and high-humidity environments, while IST versions integrate memory and temperature sensing for improved compensation.

Why Measure Hydrogen Chloride Gas?


Hydrogen chloride is a corrosive, toxic acid gas encountered in semiconductor processes, industrial cleaning and combustion emissions. Monitoring HCl helps:

  • Protect workers from respiratory and corrosive exposure.
  • Manage corrosion risks in equipment and ducting.
  • Demonstrate compliance in stack and process emissions monitoring.

Select HCl Sensor

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