What makes the tap water on board airplanes unsafe to drink?
Every single airplane toilet I've ever been to had the following (or similar) sign:
Why is drinking the tap water prohibited? And if drinking the water is prohibited, why is it acceptable to brush teeth using the very same tap?
Best Answer
You need to think of water tanks on the planes as being the same as those water coolers you see attached to the back of work trucks. They are constantly being refilled without being scrubbed out inside, overtime bacteria both noxious and harmless may build up inside.
The tanks on aircraft have an additional issue with being filled from multiple water sources, some of which may not be 100% perfect (especially those involved with international service to less developed areas).
Airlines contract to have potable water supplied to their aircraft, but as they know this is not 100% guaranteed safe, they preempt legal issues by labeling the water as such.
I have noticed less of these labels on newer or upgraded aircraft on recent fights. Perhaps they are adding a filtration system to the onboard water system.
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Where does the water on airplanes come from?
The water onboard planes comes from the municipal systems where the aircraft is parked, "which is the same water source used throughout the airport, including for water fountains and restaurants, and delivered to homes, businesses and local communities each and every day," Airlines for America, a U.S. trade group that ...What is the dirtiest thing on an airplane?
Taking the top spot as the germiest thing on an airplane is the tray table. It's loaded with bacteria. In fact, eight times more bacteria than the button you press the flush the toilet. The tray table is followed by the overhead air vent, then the flush button on the toilet, and finally the seat belt buckle.Why flight attendants avoid airplane tap water
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