What is the first factor to check when inspecting fire hydrants?

The first factor to check when inspecting fire hydrants is visibility. Ensuring that the hydrant is easily visible and unobstructed is crucial because it allows firefighters to locate and access the hydrant quickly during an emergency. If the hydrant is obscured by vegetation, snow, or debris, it can significantly delay the firefighting efforts due to the lost time in locating it.

Before any other checks, such as assessing water flow, valve condition, or color coding, firefighters need to ensure they can see the hydrant clearly. This foundational step enables them to access the hydrant efficiently and ensures that all subsequent inspections can be conducted without further delay. Thus, visibility is prioritized as it is critical in emergency situations where every second counts.