A California family booted from a United Airlines flight last week in a dispute over an infant carrier raises the question: How do parents choose the correct airline seat for their baby?

“Parents may be looking for a sticker that says ‘FAA approved,’ but the label on an approved restraint will only say, ‘This restraint is certified for use in motor vehicles and aircraft.’ So it’s easy for parents to get confused,” said family travel expert Anya Clowers of JetwithKids.com.

The Federal Aviation Administration allows children ages two and under to fly unrestrained on an airplane if seated on an adult’s lap. But the agency agrees with the National Transportation Safety Board, the American Academy of Pediatrics and other groups that children are safer when restrained in their own seats.

Melissa Bradley said she purchased a separate seat for her 1-year-old daughter and boarded a United flight on Jan. 26 with an FAA-approved infant carrier. But Bradley discovered that her child’s assigned seat was too narrow to accommodate the carrier. She mentioned the problem to a flight attendant, but ultimately was removed from the plane for being disruptive and rebooked on a later flight.

FAA regulations state that if an approved child-restraint system (CRS) doesn’t fit in an airplane seat, the airline must “accommodate the CRS in another seat in the same class of service.”

“There’s not a lot of ambiguity in that statement,” said NTSB Chairman Deborah Hermann.

Choosing the right seat
But buying the right seat can be tricky. Some child-restraint systems are approved for use in motor vehicles but not for airplanes. The current harness-style Child Aviation Restraint System (CARES) is approved for use on airplanes but not in cars.

To add to the confusion, the FAA doesn’t publish a list of approved makes and models of child-restraint systems. For that, parents must search family travel and company websites that may or may not be inclusive or up-to-date. Then they must make sure the child-restraint system they choose has that FAA certification label.

JetwithKids.com lists and reviews some FAA-approved child seats, but Clowers said she is unaware of any site that has an all-inclusive list.

Once parents have chosen an FAA-approved child-restraint system, they must then learn how to use that seat and seek an airplane seat assignment that matches their needs.

In December, the FAA posted an instructional video on its website showing how to properly install a child-restraint system on a plane. When it comes to getting a seat assignment, though, guidelines and reservation systems can cause confusion. For example, a child-restraint system should be put in a window seat, so that it doesn’t block the emergency exit path for other passengers. Approved child carriers cannot be used in, or in front of, exit row seats. And although bulkhead seats and premium seats offer extra inches, those seats are not always available and sometimes require extra fees.

The type of aircraft also can affect fit, said FAA spokesperson Alison Duquette. “Not all child safety seats fit, but the seats that are approved should fit.”

But Sarah Tilton, child passenger safety advocate at car seat manufacturer Britax, warns that “compatibility issues between car seats (rear or forward facing) and aircraft seats could increase as we see airlines decreasing the leg room to accommodate more passengers in the cabin. This decreasing of leg room will limit the space to install a car seat rear-facing.”

Stay calm
As Bradley and some other parents have discovered, even when parents call ahead to alert an airline that a ticketed passenger will be using a child-restraint system, sometimes seats are too small to allow proper installation.

“Airlines are required to accommodate the CRS in the same class of service,” said Clowers. “Do not give in and check the seat. Risking a child’s safety is not the answer. Speak with a supervisor and remain calm.”

“Remaining calm can be the tough part,” said Dr. Marilyn J. Bull, co-medical director of a program that studies child seat safety at Riley Hospital for Children in Indianapolis, Ind. “It’s hard enough to fly with young children and then add hassles with seats on top of that. Many times parents don’t know the things they should ask or do.”

Airline gate agents and crew members sometimes don’t seem to know what to do either.

Some parents have been told incorrectly that they must check an FAA-approved carrier and travel with their child on their lap. And Bull recently sat a row ahead of a mother who had dutifully strapped her two children into non-FAA-approved booster seats in preparation for a flight. “The flight attendant kept telling the mother that she had to take her children out of those booster seats, but couldn’t explain to the mother why.”

“Perhaps the bigger issue here is that the airlines don’t appear to know the FAA regulations, and the flight attendants don’t appear to be concerned with getting to know them,” said Kate Hanni, founder of FlyersRights.org. “Our babies deserve better.”

But Sara Keagle, a flight attendant who writes the Flying Pinto blog, takes issue with the implication that flight attendants don’t know FAA regulations. “I have never been on a flight where we had to have a car seat removed,” she said. “I believe flight attendants are up to speed on the rules.”

Still, NTSB chairman Hermann said she’d like to see better information conveyed to flight crews about what to do when an FAA-approved child restraint seat doesn’t fit in its assigned airline seat.

“This is an issue that parents should not have to argue with flight attendants about when they’re taking their baby on a trip,” she said. “Parents should not be penalized for doing the right thing.”

Resources for flying with babies

• Before you go, read the FAA’s “Childproof your flight” brochure.

• Watch the FAA’s video on how to properly install a child-restraint system in an airplane seat.

• To report problems regarding the use of an FAA-approved child-restraint system on a flight to your airline’s customer service department, the Aviation Consumer Protection Division at the U.S. Department of Transportation at (202) 366-2220 and to the FAA hotline at 866-TELL-FAA.

Traveling with baby? Get the right airplane seat originally appeared on msnbc.com