WASHINGTON (AP) -- Airline passengers in the U.S. will be allowed to bring most cigarette lighters on board again starting next month, freeing airport screeners to spend more time searching for explosives.

And the rule against bringing more than 3 ounces (85 grams) of breast milk aboard is being relaxed to accommodate traveling mothers.

Starting August 4 air travelers will be allowed to carry-on disposable butane lighters, such as Bics, and refillable lighters, like Zippos, the Transportation Security Administration announced Friday. But torch-style lighters, which have hotter flames, will still be banned.

"Explosives remain the most significant threat to aviation," said TSA administrator Kip Hawley. By enabling our officers to focus on the greatest threats, we are using our officers' time and energy more effectively and increasing security for passengers.''

Lighters are the leading item seized at airport checkpoints, an average of more than 22,000 a day. It costs TSA $4 million (euro2.9 million) a year to dispose of them because they contain hazardous materials.

The other rule change on August 4 applies to mothers -- or anyone -- wanting to bring more than 3 ounces of breast milk onto an airplane. Under current rules, the passenger carrying the milk must be accompanied by an infant, but the new rules drop that requirement. The liquid will still have to be declared to screeners who might request additional inspection.

"This rule has been a pain for working mothers who pumped breast milk while on a business trip without their child and wanted to carry more than three ounces home with them.'' said TSA spokeswoman Ellen Howe. "They had to throw larger amounts in the trash and that was not only wasteful but emotionally charged.''

Congress banned lighters from flights after Richard Reid used matches to try to light explosives hidden in his shoes while on a Paris-to-Miami flight in 2001. Lawmakers worried that Reid might have succeeded if he had had a lighter. The lighter ban took effect in April 2005.

The United States was the only nation in the world to prohibit carry-on lighters, and last year Congress gave the TSA administrator discretion to drop the ban if he decided it was not enhancing aviation security. Other items which are not banned can be used to ignite a bomb, including matches and small batteries.

The new rules for breast milk are the third adjustment of carry-on rules in the last year based on security risks, effectiveness studies and feedback from TSA workers, airports and travelers.

On August 10, 2006, a complete ban on liquids, gels and aerosols was implemented immediately after a thwarted terror plot in Britain aimed at blowing up trans-Atlantic flight headed to the United States. That ban was revised last September to allow travel-sized amounts in 3-ounce containers contained in one clear, zip-top plastic bag per traveler.

• Bomb Hoax at Ibiza Airport Affects 13,000 Travelers
• Fantastic Flight Decks to Fly You Safely
• Pilot Group Calls for Runway Extensions to Boost Safety