Royal Caribbean and Carnival offer advice on how to avoid a serious problem

Cruise passengers often do things that many of them consider rude.

Someone who is a jerk on land doesn’t inherently become more considerate of others when at sea. Some people use being on vacation as an excuse for their terrible behavior.

Many of the unconsidered common things that some passengers do have simply become incorporated into the cruise experience. Some people will always wake up early to claim sunbeds and then leave them unused for hours.

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Cruise lines will never be able to create a fully fair elevator system where pushy people don’t cut the line. (Royal Caribbean’s new elevator technology does a good job of curtailing this behavior.) Plus, you’ll always find people smoking on the balconies and people picking up huge plates of food at the buffet only to abandon it.

Some of these things, like smoking where you shouldn’t, can incur the wrath of your chosen cruise line. Most other actions and behaviors go largely unpunished because their overall impact on others is minimal.

Yes, it stinks to have someone push their way ahead of you in line, and not being able to easily find a pool chair is annoying. But neither situation spoils your vacation.

There is, however, one thing you should never do on a cruise ship that many people, even those who aren’t trying to be careless, still do, and the effect can be catastrophic.

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A cruise ship bathroom on the Celebrity Reflection

Image source: Dan Kline/Come Cruise With Me

Beware of the cruise ship toilet

Cruise ships have a common sewage system. This means that if you flush a prohibited item down the toilet, it can cause problems not only for your space, but for dozens, perhaps hundreds, of other booths.

It’s really important that you don’t flush anything down the toilet other than the toilet paper provided by the cruise line.

Carnival brand ambassador John Heald addressed the issue in a recent Facebook post.

“Yes, Luigi and all our plumbers hate people who bring their own toilet paper and wet wipes,” he wrote. “That’s because despite the signs asking you not to flush them down the flush toilet, they still do.”

He asked passengers to be more careful as a clogged toilet can inconvenience hundreds of passengers. Heald made it clear that people should not bring their own toilet paper from home.

“And that leads to Luigi having to put on his long glove and shove his arm into a pipe full of devil dumplings so the toilets in that section of the cabin start running again,” he added.

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Royal Caribbean shares a similar warning

Royal Caribbean has signs in its bathrooms and has a video that plays on its internal channel that shows all the things passengers shouldn’t take in the water.

These items include some things you can plausibly see being washed, like diapers and sanitary products, as well as others you can’t imagine people washing like fruit and car keys.

The cruise line also states that you are not allowed to bring your own toilet paper from home. They provide cheap toilet paper, or at least thin and inconvenient toilet paper, for a very specific reason.

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“Cruise ships must use a thin toilet paper that is suitable for RV, portable toilet or marine use. It is specially designed to break easily and quickly into storage tanks, preventing any nasty clogging,” according to the Royal Caribbean Blog. “Marine sewage systems are complicated and therefore cannot process the thicker, fluffier toilet paper you’re used to at home.”

Royal Caribbean will confiscate any toilet paper brought on board. Additionally, you should not dispose of tissues, even those that can be disposed of on land, in the cruise ship toilet.

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