OSHA 30 Hour Construction Program Practice Test

When welding stainless steel, workers should be protected from high concentrations of which substance?

1. Ozone

2. Nitrogen dioxide

3. Carbon monoxide

4. Sulfur dioxide

The correct answer is: Nitrogen dioxide

When welding stainless steel, workers should be especially protected from high concentrations of nitrogen dioxide. This gas can form when nitrogen in the air reacts with the high heat produced during welding processes. The presence of nitrogen dioxide is particularly concerning because it is a toxic fume that can irritate the respiratory system, lead to respiratory diseases, and cause various other health issues with prolonged exposure. In welding, particularly with materials like stainless steel that require intense heat and can generate significant fumes, the release of nitrogen oxides is a common hazard. Effective ventilation and appropriate respiratory protective equipment are essential to minimize exposure to these harmful fumes during welding operations to ensure the safety and health of the workers involved.