How does sulfur dioxide (SO2) affect workers’ health?

Sulfur dioxide (SO₂) is a colorless, odorless gas mainly produced from the combustion of fossil fuels such as coal, oil, and gasoline. It can also be generated during the mining and processing of sulfur ores. SO₂ is a common environmental pollutant and has significant impacts on human safety and health.

Currently, the emission of SO₂ is increasing, leading to worsening air pollution. In this article, we will explore the effects of SO₂ on the environment and human health, especially for workers exposed to potential SO₂ environments.

1. What is Sulfur dioxide (SO₂)?

SO₂ is a chemical compound known as sulfur dioxide, which is primarily formed when sulfur is burned. SO₂ is characterized as an acidic oxide; it reacts with water to form sulfurous acid (H₂SO₃).

SO₂ is a gas, colorless, heavier than air, with a pungent odor. It is toxic and soluble in water. SO₂ is a strong reducing agent. Additionally, this gas can cloud lime water and decolorize solutions of Bromine and rose-colored solutions.

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2. Sources of SO₂ emissions in production processes

Sulfur dioxide (SO₂) is a characteristic gas in industrial production activities, causing pollution and directly affecting human activities.

SO₂ is generated in the burning of wood, coal, gas, and organic materials such as waste; however, most environmental SO₂ emissions come from industrial processes such as thermal power, chemical manufacturing, metallurgy, and boiler combustion.

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3. Industries where SO₂ is hazardous to workers

Some industries involve worker exposure to sulfur dioxide (SO₂), posing health risks. Key industries include:

• Thermal power industry: Workers in power plants, especially near exhaust pipes, may be exposed to high SO₂ concentrations.
• Metallurgical industry: Metal processing plants (aluminum, copper, lead, zinc, steel) may produce SO₂ during smelting and chemical treatment.
• Chemical processing: Production of sulfuric acid, sulfate compounds, and other sulfur chemicals can be potential SO₂ sources.
• Mining and processing sulfide ores such as copper, lead, zinc, and other sulfide ores can generate SO₂ during crushing and smelting.
• Food processing, such as sugar refining and beer production, may generate SO₂ as an additive or preservative.
• Other jobs or industries with potential SO₂ exposure.

For these workers, safety measures, personal protective equipment (PPE), and pollution control are crucial.

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4. How SO₂ affects worker comfort

Sulfur dioxide (SO₂) can significantly impact worker comfort. Effects include:

• Respiratory issues: irritation and damage to airways, causing difficulty breathing, coughing, and discomfort.
• Nasal and throat irritation: sneezing, runny nose, itching, sore throat, and difficulty swallowing.
• Eye irritation: tearing, redness, and eye pain.
• Psychological discomfort: exposure can cause stress, anxiety, and negatively impact work performance.

Ensuring worker comfort requires safety measures, pollution control, proper ventilation, and PPE like gas masks.

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5. Permissible exposure limits for SO₂ at the workplace

According to QCVN 03:2019/BYT National Technical Standard for permissible exposure limits of 50 chemical factors in the workplace:

Table 1. Maximum permissible exposure limits for chemical factors at the workplace.

Unit: mg/m³

No.	Chemical Name	English Name	Chemical Formula	Molar Mass	CAS Number	TWA	STEL	IARC Toxicity Group
45	Sulfur dioxide	Sulfur dioxide	SO2	66.06	7446-09-5	5.0	10	3

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6. Diseases caused by long-term exposure to hazardous SO₂

SO₂ exposure causes shortness of breath, throat irritation, nasal congestion, and is a primary factor in diseases such as pneumonia, eye pain, and respiratory inflammation.

SO₂ is a hazardous environmental pollutant found in heating systems, cigarette smoke, vehicles, and industrial emissions. It contributes to air pollution and acid rain, leading to tree death and structural corrosion.

Long-term exposure to SO₂ can cause:

• Respiratory diseases: pneumonia, rhinitis, sinusitis, cough, breathing difficulties. People with asthma or acute respiratory conditions are more sensitive.
• Eye effects: tearing, irritation, pain, possible conjunctivitis or corneal damage in severe cases.
• Skin effects: irritation, bleeding, cracking, and in severe cases, burns or wounds.
• Long-term exposure may impact the nervous, cardiovascular, and digestive systems. Studies link SO₂ to heart disease and hypertension risks.
• Environmental hazard: SO₂ contributes to acid rain, vegetation damage, and material corrosion.

Limiting exposure and maintaining a healthy environment is essential for protection.

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7. Measures to reduce the impact of SO₂ on worker health

To minimize SO₂ effects, the following measures are recommended:

• Implement workplace environmental management to reduce exposure, improve ventilation and dust extraction, use appropriate PPE (e.g., chemical masks), and establish safe work zones.
• Train workers on SO₂ risks, symptoms, proper PPE use, and safety procedures in SO₂ environments.
• Conduct regular health checks to detect SO₂-related issues early.
• Comply with safety standards and regulations related to SO₂ exposure.
• Apply pollution control technologies to reduce industrial SO₂ emissions.
• Worker training: Teach employees how to protect their health in hazardous environments.
• Periodically conduct workplace environmental monitoring to evaluate risks and prevent occupational diseases.

Preventive measures and strict safety protocols are essential to minimize SO₂ health risks.

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8. National workplace environmental monitoring center

Nam Viet Workplace Environmental Monitoring Center is a professional unit monitoring and measuring workplace environmental quality across all provinces in Vietnam. With experienced environmental monitoring specialists, the center uses modern instruments to ensure accuracy and reliability.

REGISTER FOR WORKPLACE ENVIRONMENT MONITORING SERVICE

In addition to monitoring services, the center assists clients in planning, managing, and tracking workplace environmental issues, prioritizing customer satisfaction and delivering optimal solutions.

Nam Viet’s monitoring center has become a reputable workplace environmental monitoring unit in Ho Chi Minh City with goals:

• Maintain brand reputation and service quality.
• Provide the best and most suitable services for clients.
• Leverage experienced engineers and specialists to protect the environment and benefit enterprises.

• Clients receive professional service from monitoring experts with competitive pricing.

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9. Workplace environmental monitoring service pricing

To help businesses conduct professional and effective workplace environmental monitoring, Nam Viet provides clients with a pricing table for workplace environmental monitoring services with quality and reasonable costs.

• The pricing table details service costs, including travel, measurement, analysis, and reporting. Clients can trust the accuracy and reliability of monitoring reports.
• We ensure competitive and fair pricing while providing fast and professional consultation.
• Clients can easily select service packages suited to their needs, ensuring maximum satisfaction with professional service quality.