The cruise bill of rights is legally enforceable because it’s part of your contract with the cruise line. (iStock)

If you’re an experienced traveler, maybe you know about the Department of Transportation’s 24-hour rule for airline ticket purchases, or EU 261, the European consumer protection regulation for air travelers, or the Fair Credit Billing Act.

But what about the cruise bill of rights? The flat-tire rule? The Lanham Act?

Turns out there are a lot of rules, regulations and policies that benefit travelers. Travel companies sometimes go to great lengths to avoid mentioning that you have rights. That’s because it could cost them money in the form of refunds or penalties.

At a time when “regulation” is becoming an epithet, it may behoove you to take a moment to appreciate one or two of the more obscure rules. Who knows, maybe they could improve your next trip.

First, just in case you didn’t know: The 24-hour rule generally allows customers to cancel airline ticket reservations within 24 hours of making the booking and receive a full refund. There are exceptions for travel booked within a week, hence the “generally.” EU 261 is the European regulation that makes airlines pay customers when their flights are delayed or canceled. And again, certain exceptions apply. The Fair Credit Billing Act protects customers when fraudulent purchases are made with their credit cards and allows them to dispute the bogus charges.

You knew all that, didn’t you? But how about these:

The Lanham Act: This is a fairly broad federal statute that says anyone who makes a “false or misleading description of fact” is in violation of the law. Specific to travel, it forbids a company from misrepresenting the “nature, characteristics, qualities, or geographic origin” of goods, services or commercial activities. In other words, if a hotel room isn’t as advertised online or if a tour doesn’t live up to its billing, it may run afoul of federal law. Similarly, when car-rental agents imply that insurance is mandatory and offer to upsell you on their pricey policy, that could technically be a violation.

The cruise bill of rights: “Most cruise passengers don’t know they have a bill of rights set forth by the cruise lines,” says Tanner Callais, editor of the cruise website Cruzely.com. The bill of rights, adopted by the industry in 2013 to avoid more formal government regulation, gives passengers the right to leave a docked ship if it can’t provide essentials such as food, water, bathroom facilities and medical care. It also grants passengers the right to a full refund for a trip canceled because of mechanical failures and a partial refund if a trip is cut short for the same reason. The bill also promises to offer customers “timely” updates about any changes in a ship’s itinerary caused by a mechanical failure or an emergency. It is legally enforceable because it’s part of your contract with the cruise line.

The flat-tire rule: This rule stipulates that if you’re delayed and you miss your flight — because of traffic, for example — you can go standby as long as you arrive within two hours of the flight. Although I have seen this rule invoked by passengers on a regular basis, none of the airlines publicize this rule on their websites. According to former and current airline employees, some, but not all, airlines cite such a rule in internal manuals and refer to it during agent training. I’ve questioned airlines about it on numerous occasions. For example, when I visited United Airlines a few years ago, the company’s senior vice president of customer experience confirmed that it did, indeed, exist. However, even when airlines have a “flat-tire rule,” it can be unevenly applied by agents, so invoking it won’t always do you much good.

Rental-car upgrade and reciprocity rules: Like the flat-tire rule, company policies on rental-car upgrades and reciprocity are not readily available to the public. However, industry insiders have told me they exist and I have successfully invoked them myself on many occasions, so here goes: If you reserve a class of car and the location runs out of vehicles in that class, you’ll get a free upgrade into the next available class of vehicle. If the location runs out of cars, it will pay for a comparable car from a competitor. Both of these are standard practices, and often formalized as internal policies. Although they are practically universal in the car rental business, they are not widely known.

More rules and regulations that could potentially benefit travelers are constantly being added to the books. For example, a few years ago, Josh Summer, a Dallas guitarist, discovered a line in the FAA Modernization and Reform Act of 2012 that required airlines to allow passengers to carry violins, guitars or other musical instruments in the aircraft cabin, “without charging the passenger a fee in addition to any standard fee that carrier may require for comparable carry-on baggage.”

“As a musician, I have been very thankful for that obscure rule,” Summer says.

Do the rules really work? Yes, this column is filled with regular examples of how the 24-hour rule, the Fair Credit Billing Act and EU 261 can help travelers.

Even the lesser-known regulations demonstrate their effectiveness every day. Who can forget the 2008 YouTube video “United Breaks Guitars,” by the Canadian country band Sons of Maxwell, which lamented the airline’s mistreatment of the group’s guitars in the cargo hold? Since the passage of the FAA Modernization and Reform Act, complaints sent to me about damaged instruments have virtually disappeared. Likewise, the cruise bill of rights, initially criticized by consumer advocates for not going far enough, has dramatically reduced the number of grievances I’ve received about cruise ship service problems.

A polite reminder of these relatively obscure policies — many of which have existed for years — is often all that it takes to secure that upgrade or rebooking.

Taken together, the rules and regulations offer necessary protections for travelers. That’s an important thing to remember at a time when “regulation” has become a dirty word in Washington — and also a warning to anyone looking to dismantle the few rules that protect us.

Elliott is a consumer advocate, journalist and co-founder of the advocacy group Travelers United. Email him at chris@elliott.org.