Final answer:
The question relates to the specific regulations regarding the use of manually controlled fludhometer valves for flushing ballast tanks. The missing value would be the maximum percentage of flushing capacity allowed, relevant to marine or engineering safety guidelines.
Step-by-step explanation:
The question refers to the regulations surrounding the use of manually controlled fludhometer valves for flushing ballast tanks. A fludhometer is a device typically used to regulate the flow of fluids, such as water.
In the context provided, the statement likely pertains to a safety or procedural guideline for the operation of these valves within a marine or engineering environment. To maintain proper function and safety, a manually controlled fludhometer valve should adhere to a specific guideline for the amount of water flushed, as excessive volumes can cause operational issues or risk to stability.
For example, if a ballast tank must be flushed with 300% of its capacity to ensure cleanliness or stability, a fludhometer valve would control this process. However, the maximum capacity that should flow through the valve when manually controlled is missing from the question and would typically be specified in procedures or regulations relevant to the type of vessel or tank being considered.