Sulphur dioxide (SO₂) – Invisible risk

Toxic, corrosive, life-threatening

Effective gas detection protects people, systems and processes

Sulphur dioxide (SO₂) is a colorless, pungent-smelling irritant gas that is used in numerous industrial processes – including in the paper and pulp industry, chemical production, wastewater treatment, food preservation and refinery technology. Despite its industrial relevance, SO₂ poses a serious health and safety risk – especially in the event of uncontrolled release or unnoticed concentrations indoors.

Sulphur dioxide: Toxic and irritant even in small quantities

Even the smallest concentrations of SO₂ irritate the respiratory tract, eyes and mucous membranes. Respiratory patients, asthmatics, children and workers in highly exposed areas are particularly at risk. At higher concentrations, there is a risk of lung damage, edema or even life-threatening chemical burns.

Health-relevant threshold values for sulphur dioxide:

Odor threshold: 0.3-1 ppm (often perceptible too late)
AGW (occupational exposure limit value, Germany): 0.5 ppm (1.3 mg/m³)
>2 ppm: Irritation of eyes, throat and respiratory tract
>5-10 ppm: Risk of serious damage to health
>50 ppm: acute danger to life

Particularly critical: In humid breathing air, SO₂ reacts to form sulphurous acid, which additionally corrodes the lung tissue and significantly increases the toxic effect.

Non-explosive, but chemically aggressive and corrosive

Sulphur dioxide is non-flammable and non-explosive, but is a highly reactive and highly corrosive gas. In combination with humidity or water, it forms acid rain, which massively attacks machines, pipelines and building materials. The double danger – toxic + chemically destructive – makes SO₂ particularly critical in industrial plants.

Gas detectors for SO₂ – Precise detection for maximum safety

As sulphur dioxide is colorless and often escapes unnoticed, gas warning systems for SO₂ are essential for a safe working environment. Our devices detect sulphur dioxide early and reliably – stationary or mobile.

Your advantages at a glance:

Early warning from a few ppm
Long-term stable SO₂ sensors
Visual & audible alarms when limit values are exceeded
Integration into ventilation and emergency shutdown systems
Portable measuring devices for maintenance & mobile applications
Stationary systems for room air or process monitoring

Typical areas of application with increased SO₂ risk:

Our gas detectors are used wherever sulphur dioxide is produced or processed:

Paper and pulp production
Chemical processes (e.g. sulphuric acid production)
Flue gas cleaning & flue gas desulphurization
Food processing (drying, preservation)
Wastewater treatment plants & waterworks
Metal industry & recycling plants

Conclusion: Monitor sulphur dioxide safely – recognize risks at an early stage

Whether in the production process, in warehousing or in the laboratory: our gas detectors for SO₂ provide you with a reliable solution for monitoring a highly critical industrial gas. Early detection, high measurement accuracy and seamless integration into your safety structure help to minimize risks and protect people.