OHST Practice Exam

Which method is least effective in controlling exposure to airborne contaminants in an industrial setting?

1. Engineering controls

2. Administrative controls

3. Personal protective equipment

4. Local exhaust ventilation

The correct answer is: Personal protective equipment

Personal protective equipment (PPE) is considered the least effective method for controlling exposure to airborne contaminants in an industrial setting primarily because it is the last line of defense. While PPE, such as masks or respirators, can provide a degree of protection for individual workers, it does not eliminate the hazards at the source and relies heavily on proper use, maintenance, and fit. This means that if PPE is not used correctly or consistently, its effectiveness can significantly diminish. In contrast, engineering controls aim to remove hazards from the workplace, such as through the use of local exhaust ventilation, which effectively reduces airborne contaminants at the source before they can reach workers. These controls focus on altering the workplace environment or processes and are typically more effective because they address exposure directly. Administrative controls involve changes in work procedures and practices that reduce the duration, frequency, or intensity of exposure to hazards. While they can be beneficial, they still depend on human behavior and compliance, which can introduce variability in effectiveness. Thus, while PPE plays an important role in a comprehensive exposure control strategy, it is not sufficient on its own to ensure safety, making it the least effective method among the options presented.