BFL13 wrote:
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Our three tanks have their valve handles scattered here and there, with two of them over on the other side of the rig from the sewer hose connection. Means no local control over events right where you are, and no quick action if you screwed up and left one of the others open, so you are hit with a flood when you take the cap off. :( ...
This concern brings back memories of my Submarine Sea-going days. Using your parlance, we had a black tank for human waste with toilets and urinals located in various bathrooms (heads) throughout the boat. When time to "Blow Sanitary", we would make sure the dump or flush valves were shut and also shut individual valves to make doubly sure! We would then admit high pressure air into the tank and blow the contents to sea. Pity the poor soul that mistakenly opened one of the dump valves prior to the air pressure being vented out of the tank after emptying the tank contents.
Cleanup duty went to the person responsible - no matter what his Rank!:S