The department’s inspector general, Clark Kent Ervin, said training and testing has improved since the days when screeners got an advance look at tests, some of which had laughably easy answers.

Congress has been pressuring the Transportation Security Administration to improve screeners’ ability to prevent weapons and bombs from getting on planes. In April, Ervin told lawmakers that screeners performed poorly.

The report said airports would be less vulnerable with “improved selection, training and monitoring of screeners.” But it noted that screeners on their own cannot detect all dangerous items all of the time.

The report emphasized that the best way to tighten airport security is to develop better technology, which “holds the greatest long-term potential for reducing airport security system vulnerabilities and increasing the detection of prohibited items.”

TSA screeners are required by law to receive 40 hours of classroom training and 60 hours of on-the-job training. They had to pass a test to be hired and are retested every year to make sure their skills stay sharp.

The inspector general acknowledged that test questions are better, recurrent training is improved and screeners are now getting training materials that they can take home and study. The report also applauded the TSA for teaching screeners to train other screeners, which saves money because fewer outside contractors are required to do the job.

The 122-page report listed areas where the TSA’s testing and training need improvement:

Screeners didn’t receive enough hands-on practice using machines for screening checked baggage, partly because of limited access to practice equipment.

Screeners weren’t taught some basic skills they need to do their jobs, such as handling dangerous weapons and objects, repacking bags after searches, reading airline tickets and recognizing identification for travelers who claim they can bring weapons onto aircraft.

Screeners aren’t tested on when they should pat down passengers and what the passengers’ legal rights are.

Screeners aren’t tested on or trained how to physically search animals and their cages for weapons and bombs.

The report noted that screeners, who must lift heavy bags, had the highest injury rate in the federal government last year, with nearly one in five hurt on the job. The TSA only trains some screeners on proper lifting techniques, the report said. “TSA should provide thorough training, including practice, before screeners are required to lift baggage,” the report said.

The inspector general also found that some instructors coached students through tests of their skills, which may have given an unfair advantage to some students. The TSA in May issued guidelines that prohibit test administrators from helping students during their practical skills tests.

TSA chief David Stone responded that the agency is analyzing the screener training course to make sure it covers all the skills and knowledge needed to do the job.

The agency is also looking at the feasibility of creating training centers that have enough equipment for screeners to practice on.

Stone also pointed out that the TSA is conducting several pilot programs to test new screening technologies.