Detecting Hydrogen Sulphide | Gas Fact Sheet

Detecting Hydrogen Sulphide


Hydrogen Sulphide

Formula: H2S

CAS Number: 7783-06-4



Hydrogen Sulphide (H2S) is a colourless, highly toxic gas characterised by its distinct rotten egg odour. It is naturally occurring and produced through both biological and industrial processes. Despite its hazardous nature, hydrogen sulphide finds applications in various industries, from oil and gas to agriculture and healthcare.


Hydrogen sulphide is produced through both natural and industrial processes. It is generated during the breakdown of organic matter in anaerobic conditions, such as in swamps, sewage, and manure. Industrially, hydrogen sulphide is produced as a by-product of refining crude oil and processing natural gas.


Hydrogen sulphide is commonly found in crude oil and natural gas deposits. It is removed during refining processes and can be converted into elemental sulphur or sulphuric acid. Hydrogen sulphide is also used in the production of sulphuric acid, sulphur-containing chemicals, and metal sulphides.

Health and Safety Hazards:

Hydrogen Sulphide is highly toxic, even at low concentrations. Exposure to high levels can lead to rapid unconsciousness, respiratory failure, and fatal consequences. The odour of Hydrogen Sulphide is detectable at low concentrations with a STEL of 5 ppm. However, prolonged exposure can desensitise the sense of smell, increasing the risk of accidental exposure.

Personal protective equipment (PPE), including respirators, gas masks, and chemical-resistant clothing, should be worn when working with or near Hydrogen Sulphide. Adequate ventilation and gas detection systems are essential to minimise the risk of exposure to Hydrogen Sulphide in industrial settings.


Hydrogen Sulphide is a versatile gas with significant industrial applications, but its toxicity presents considerable health and safety challenges. Proper handling, monitoring, and mitigation measures are essential to ensure the safe use of hydrogen Sulphide and minimise its environmental impact.


What we recommend

Crowcon T4 Portable Gas Detector | Crowcon Tetra 4

The Crowcon T4 (Tetra 4) gas detector is a tough and affordable option that keeps you safe. Capable of detecting minute amounts (parts per billion) of four common dangerous gases, which include:

  • Carbon Monoxide (CO)
  • Hydrogen Sulphide (H2S),
  • Flammable Gases (LEL)
  • Oxygen Depletion (02).

For more information on the Crowcon T4 Portable Gas Detector | Crowcon Tetra 4, click here: Crowcon T4 Portable gas detector | CO, H2S, LELs and Oxygen (


Honeywell BW Flex 4 Portable Gas Detector

The Honeywell BW Flex 4 is a portable multi-gas detector that offers a high level of flexibility and reliability for use in a wide range of hazardous environments. It can be configured to detect up to four different gases simultaneously, and it features several advanced features that make it ideal for a wide range of applications.

For more information on the Honeywell BW Flex 4 Portable Gas Detector, click here: The Honeywell BW Flex 4 portable gas detector | Rockall safety


Drager X-am 2500 Gas Detector

The Drager X-am 2500 gas detector is equipped to seamlessly detect combustible gases and vapours, including Oxygen, CO and H2S. It has been specially developed to cope with heavy industrial environments such as mining, construction, and refineries.

The X-am is easy to use and maintain. It has a large, easy-to-read display and simple controls. The X-am also comes with a variety of accessories, including a shoulder strap, carrying case, and calibration kit.

The X-am 2500 is technologically advanced and houses sturdy electrochemical sensors that are highly resistant to silicone and hydrogen sulphide, ensuring reliable and continuous ATEX protection. For more information on the Drager X-am 2500 Gas Detector, click here: Drager X-am 2500 Gas Detector | O2, CO & H2S | Rockall Safety


For more information on Hydrogen Sulphide, download the gas fact sheet here: Detecting Hydrogen Sulphide



Written by Rhys Redrup

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