745 Welding, Cutting, and Brazing Safety

Top 10 Chemical Exposures

6. Nickel

Nickel is a silvery-white metal commonly found in stainless steel, metal alloys, batteries, and coatings.

Exposure Risks: It is widely used in industrial applications due to its strength, corrosion resistance, and conductivity. However, nickel is a well-known allergen and sensitizer.

Health Effects: Prolonged or repeated skin contact can lead to allergic contact dermatitis, particularly in individuals who are sensitive to it. Inhalation of nickel compounds—especially in the form of fine dust or fumes during processes like welding, grinding, or smelting—can irritate the respiratory tract and has been linked to more severe health outcomes.

Chronic exposure, particularly through inhalation, has been associated with respiratory conditions such as asthma and, more significantly, an increased risk of lung and nasal cancers. Due to its carcinogenic potential and ability to cause sensitization, nickel exposure is regulated in many workplaces under occupational health and safety guidelines.

7. Ozone (O₃)

Ozone is a highly reactive gas composed of three oxygen atoms. While it occurs naturally in the upper atmosphere where it forms a protective layer against ultraviolet (UV) radiation, ozone at ground level is a harmful air pollutant.

Exposure Risks: In industrial settings, especially during arc welding, UV light interacts with oxygen in the air to generate ozone.

Health Effects: Although it is invisible and odorless at low concentrations, ozone is extremely toxic to the respiratory system. Even short-term exposure can cause symptoms such as coughing, throat irritation, chest tightness, and shortness of breath.

At higher concentrations or with prolonged exposure, ozone can lead to inflammation of the lungs, reduced lung function, and permanent respiratory damage. Workers exposed to ozone may also experience exacerbation of pre-existing conditions such as asthma or bronchitis.

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