OHST Practice Exam

General or dilution ventilation is appropriate in all of the following except?

1. When small quantities of contaminants are released

2. The toxicity of contaminants is low

3. Air is not drawn through the workers breathing zone

4. Corrosion may occur to equipment in the workroom

The correct answer is: Corrosion may occur to equipment in the workroom

General or dilution ventilation is primarily designed to control the concentration of airborne contaminants by mixing contaminated indoor air with fresh air. This method is most effective in situations where the release of contaminants is small or where the toxicity of those contaminants is low. It relies on natural air movement or mechanical systems to circulate air, thus diluting the concentration of contaminants. In scenarios where corrosion may occur to equipment in the workroom, it indicates a potential for significant exposure to corrosive substances, which is not suitable for general or dilution ventilation. This is because, in such environments, specialized ventilation systems or local exhaust ventilation would be more appropriate to directly capture and remove harmful contaminants before they can cause corrosion or other safety hazards. Using general or dilution ventilation in this case could lead to insufficient removal of harmful substances, potentially leading to equipment damage and adverse health effects for workers. Therefore, general or dilution ventilation is not appropriate when conditions involve corrosive agents, necessitating more targeted approaches to ensure safety and equipment integrity.