John Pistole's appearance Thursday before a House Homeland Security subcommittee was his first in Congress since the TSA announced small knives, golf clubs, hockey sticks and other items no longer would be prohibited in airplane cabins.
"These are not things that terrorists are intending to use," Pistole told the subcommittee.
Pistole said identifying people -- not things -- as potential threats will be a more efficient and safer security method, the Los Angeles Times reported.
Pistole testified terrorists who plotted against the United States since the Sept. 11, 2001, attacks have tried to sneak non-metallic explosives aboard planes.
Although those efforts have failed so far, the TSA has tried to improve its understanding of the devices and reconcile that with making traveling easier for passengers.
"The problem with these 'risk-based assessments' is that they put the government on a road to judging its own citizens in secret, with no fair recourse for people unfairly judged," said Jay Stanley, a policy analyst at the American Civil Liberties Union.
"And how much information do you need to know about a person to prove they're not a terrorist? The government will never have enough, and the privacy intrusions will just keep growing."
The carry-on items changes, effective April 25, should reduce the time passengers clear airport security, Pistole said. Other efforts to speed up the security process include reducing screening requirements for children and seniors.
The TSA also is looking into ways to pre-check more passengers so that people it has identified as non-threatening can get to the boarding areas more quickly.