They also point out that it "lowers risk, both in not having unknown persons delivering 5 gallon bottles into your facility" and not having employees kill themselves trying to change them. Or, as where I teach and where they should know better, the closets are filled with empty bottles waiting to be picked up.
Jason Boyd of Dobbins, the first LEED accredited plumbing salesman I have ever met, also showed me this new Sloan solar powered dual flush valve. There isn't usually much sun in bathrooms, but there is light, enough of it to operate the valve, eliminating the need for transformers, wiring and the use of electricity. What is more interesting is that it is dual flush, the full 1.6 gallons per flush for solid waste or 1.1 gallon for liquid. There are buttons for users to choose but nobody likes touching these things, so it also has a detector that judges how much water to use depending on how long one sits on the toilet.
I would not have thought that this was a great way to figure it out, thinking perhaps a scale built into the seat to calculate how much lighter the user gets might be more effective, but they claim:
Exhaustive research and extensive field trials have proven the Dual-Flush Sensing Algorithm to be a reliable and efficient method of controlling flush volume.
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