FILE - In this Sept. 26, 2006, file photo, knives of all sizes and types are piled in a box at the State of Georgia Surplus Property Division store in Tucker, Ga., and are just a few of the hundreds of items discarded at the security checkpoints of Hartsfield-Jackson Atlanta International Airport that will be for sale at the store. Airline passengers will be able to carry small knives, souvenir baseball bats, golf clubs and other sports equipment onto planes beginning in April 2013 under a policy change announced Tuesday, March 5, 2013, by the head of the Transportation Security Administration administrator John Pistole. (AP Photo/Gene Blythe, File)
Small knives are set to be permitted in carry-on luggage on flights, in a change to current guidelines announced by the TSA today.
Knives with blades no more than 2.36 inches in length from tip to where the blade meets the handle or hilt will be approved for carry-on.
The blade must be no more than half an inch in width.
The TSA also announced toy bats and sporting equipment such as hockey sticks and golf clubs will also be allowed on board aircraft.
The TSA said the changes were made after a committee had reviewed the agency's prohibited items list.
"This decision aligns TSA with International Civil Aviation Organization standards and our European counterparts," the TSA said in a statement. The changes are set to come into effect on April 25.
But the changes were opposed by two industry groups.
The Flight Attendants Union Coalition, representing nearly 90,000 Flight Attendants said the decision was ''poor and shortsighted''.
''Continued prohibition of these items is an integral layer in making our aviation system secure and must remain in place,'' said the union in a statement.
"As the last line of defense in the cabin and key aviation partners, we believe that these proposed changes will further endanger the lives of all Flight Attendants and the passengers we work so hard to keep safe and secure.
"Flight Attendants are the front line safety and security professionals on board every commercial passenger aircraft in this country and must be given the tools and training to protect ourselves, our passengers and the aircraft.''
The Association of Professional Flight Attendants, representing over 16,000 American Airlines employees, asked the TSA to re-evaluate the policy and questioned why ''such a momentous decision'' was made without consulting the group.
APFA ''categorically rejects a proposal to allow knives of any kind in the cabin,'' said Glading.
APFA Safety and Security Coordinator Kelly Skyles said relaxing restrictions on hockey sticks, golf clubs, and ski poles, meant ''the potential for passengers getting hit with these items during boarding and deplaning. It's a recipe for disaster."
© 2013 CBS Interactive Inc. All Rights Reserved.