For the first time in a decade, the Transportation Security Administration implemented significant changes in screening procedures on Thursday at Salt Lake City International Airport.

Until passengers and officers become more accustomed to them, it warns that passing through security may take some extra time — and advises arriving at least 90 minutes before flights.

The main change is that for X-ray screening of carry-on bags, all electronics larger than a cellphone must be removed and placed flat in a bin with nothing stacked above or beneath them — similar to what has long been required for laptop computers.

That includes most tablets, iPads, Kindles, cameras, video players and speakers, among other things. Other than laptops, those electronics may be placed in bins with other items, but with nothing above or below them.

(Steve Griffin | The Salt Lake Tribune) TSA agent Suzanna Coria shows some of the electronic devises that need to be in their own bin under new stronger security procedures at the Salt Lake International Airport and five other Utah airports Thursday October 5, 2017.

TSA spokeswoman Lorie Dankers said intelligence shows “that terrorists continue to target commercial aviation. We know that they are aggressively pursuing innovative methods to disrupt the aviation system by finding ways to smuggle explosives into various consumer items, with a focus on electronics.”

She added, “TSA constantly evaluates and updates our screening procedures to keep the traveling public secure by staying ahead of these evolving threats.”

Danker said TSA has been testing new procedures for the past 18 months at 10 airports. The agency announced in July that it would begin training to allow their implementation nationwide.

They were put in place Thursday in Utah at airports in Salt Lake City, Ogden, Provo, Cedar City, St. George and Wendover. Dankers said the new procedures will be used at all airports nationwide by early next year.

TSA is encouraging travelers to organize their carry-on bags and keep them uncluttered to make the screening process easier.

“If you have so much stuff in your bag that they don’t get a clear view” in X-ray images, “your bag will be re-run and you will potentially get a bag check, and you will delay yourself and other people,” Dankers said.

TSA now has officers in front of X-ray machine areas advising people what must be removed from bags.

Chris Detrick | The Salt Lake Tribune Passengers go through security at Salt Lake City International Airport Thursday January 15, 2015.

“Passengers will receive very specific instructions about what is required of them. So please listen to our officers … because they may be giving you information that will help you get through the security screening process quicker,” Dankers said.

Exempt from new rules are travelers in dedicated TSA Precheck lanes, who registered by paying a fee and providing extra background information about themselves. They may keep electronics in their bags. “It’s another reason to become a trusted traveler” through the program, Dankers said.

She notes that TSA is making no changes about what travelers may bring through checkpoints. That includes, as previously allowed, bringing liquids in containers of less than 3.4 ounces placed together in a clear quart-sized bag that must be placed in bins. TSA’s website has a list of items that are allowed, or banned.

Because travelers will be taking more items out of bags now, Dankers suggested that they tape a calling card or identification to important electronics such as laptops in case they are left by accident at checkpoints.

“Over the weekend, 23 laptops were left in the Newark airport,” for example, she said.

Dankers said that testing shows that over time, the new procedures are just as fast as the old ones — but they require more time initially as officers and travelers get used to them.

(Steve Griffin | The Salt Lake Tribune) Security line at the Salt Lake International Airport in Salt Lake City Thursday October 5, 2017.