Which step should be completed first when developing a ventilation strategy for a facility with mixed hazards?

• A. Conduct hazard assessment
• B. Install LEV at all sources
• C. Increase outdoor air without filtration
• D. Proceed to containment plan

Answer: (A)

Starting with a hazard assessment sets the foundation for a sound ventilation strategy. By identifying what contaminants are present, where they come from, how much is produced, and how people might be exposed, you gain the essential information to tailor controls to the actual risks. In a facility with mixed hazards, different substances may require different approaches—some emissions may respond best to local exhaust ventilation at the source, others to increased general ventilation or targeted filtration, and some may demand containment or zoning. The hazard assessment tells you which sources are the priority, the expected emission rates, and the exposure pathways, so you can design the system to remove or dilute contaminants effectively while avoiding unnecessary energy use or overbuilding. It also aligns the plan with safety standards and the hierarchy of controls, ensuring that the most protective measures are applied where they are needed most. Jumping straight to installing local exhausts at all sources, increasing outdoor air without filtration, or skipping containment planning can lead to a misfit system that either misses hazards or wastes resources. Once hazards are understood, you can proceed to select and implement the appropriate containment and ventilation measures with confidence.