Sometimes, cruise lines ban things because they’re dangerous.

For obvious reasons you can’t bring explosives, weapons, firearms and many other potentially scary items on board. You may want to go hunting when you reach your destination, but guns aren’t allowed under any circumstances.

In other cases, items are banned because they present a danger to the cruise ship.

Related: Carnival Cruise Line makes a menu change passengers demanded

You can’t sail with an iron, a coffee pot, a steamer or basically anything with a heating element. You also can’t bring a surge protector, and Royal Caribbean even bans multiplug outlets.

Candles and torch lighters are also banned. Those items are all outlawed because they present a fire risk, and fires on ships are incredibly dangerous since they can spread quickly.

In other cases, items are prohibited because they take revenue away from the cruise line. You can’t bring travel routers or satellite internet connections on board because they might interfere with ship operations, and they help people get around paying for multiple internet devices.

Cruise lines aren’t banning things arbitrarily. They’re thinking of the well-being of the ship and its passengers first and then protecting the company’s revenue.

Carnival Brand Ambassador John Heald recently fielded a question about an item the company does not allow people to use on board. This one might surprise you in two ways.

First, you might be surprised at the ban. Second, you may not realize this was allowed in the first place.

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Cruise ship cabins have TVs but they may not work like the ones at home.

Image source: Carnival Cruise Line

Carnival does not allow this in its cabins

Cruise passengers often ask about using streaming devices connected to their in-cabin televisions. In some cases that’s possible, but usually the cruise lines have found ways to block their use.

In some cases it’s not exactly against the rules. Royal Caribbean does not ban streaming players, but in most cases it’s impossible to get them to work even if the passenger can access the ports on the televsion.

One Carnival Cruise Line passenger wants to hook up a different kind of popular technology.

“I have some avid video gamers coming with me for the first time, and they wanted to bring something so they could play games hooked up to the TV in the room,” the unidentified poster wrote. “I read an article that nothing can be hooked up to the TVs and that the ports are blocked. I’ve never tried so I wasn’t sure if this is true?”

Heald made the cruise line’s policy on videogame systems clear.

“That is correct, I’m afraid they can’t be hooked up to the television televisions for operational reasons,” Heald wrote.

He then tried to frame the rejection of what the passenger wanted as a positive.

“I would hate for them to bring all this equipment for nothing. So please let them know. I’m sure they will have a wonderful time though and there is so much for them to do,” he added.

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Carnival has these items on its banned list

Sometimes an item isn’t allowed, even though it’s not on the cruise line’s banned-item list. That’s not the case here: Carnival specifically does not allow hooking up any items to its TVs.

“Digital Cameras/Camcorders, DVDs/VCRs, USB sticks, iPods, Nintendo/X-Box Play Units cannot be used with the TV in the guest stateroom or suite as the connection ports are disabled,” it posted on its website.

Passengers can bring standalone videogame players or even a portable DVD player as long as they use headphones when using these items in a public area.

Carnival also has some other rules regarding music and electronics passengers may not know about:

Musical instruments: Are allowed, [but] if a noise complaint is received, the instrument will be confiscated and returned to the guest on debarkation morning.Google-type glasses are permitted on board in public areas, but cannot be worn at any gangway operation.

One popular technology item can be used only in ports (and many ports don’t allow them).

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“Drone(s) are allowed, but must be held in the custody of the Chief Security Officer and must be checked out/in by the owner for PORT USE ONLY, ” the cruise line says on its website (complete with capital letters).

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