Which statement is correct regarding large flooded cell installations?

The statement about large flooded cell installations being installed in a restricted access room with safety measures is correct due to the inherent risks associated with flooded lead-acid batteries. These batteries contain sulfuric acid and can produce explosive gases, especially during charging. Therefore, safety protocols necessitate that their installation occurs in areas that limit access to only trained personnel. This helps prevent accidents and ensures that appropriate safety measures, such as ventilation and protection from unauthorized access, are in place.

The other statements may lack accuracy regarding the specific practices and characteristics of flooded cell installations. For instance, while maintenance is essential, the specific requirements can vary and may not necessarily encompass all the intervals mentioned. Flooded cells also tend to outgas during the charging process, not exclusively when being recharged, and maintenance can involve various personnel, not strictly competent electrical contractors. This highlights the importance of understanding the context and proper handling of flooded cell batteries in a safety-conscious manner.