The new PreCheck fast-pass security screening program at Sea-Tac Airport has been expanded beyond Alaska Airlines passengers to include eligible fliers on American, Delta, United and US Airways.

Those eligible to participate — for now, passengers considered low security risks either because they are high-mileage frequent fliers invited by those airlines to apply for PreCheck or members of the Global Entry, Sentri or Nexus (U.S./Canadian/Mexican border-crossing programs) — can use a special lane set up at Checkpoint No. 5 in the north end of the Sea-Tac terminal. There, they can pass through security without removing jackets and shoes, or taking liquids and laptops out of carry-ons. They also walk through metal detectors instead of full-body scanners.

Not everyone declared eligible for PreCheck sails through security every time. That's because the federal Transportation Security Administration operates PreCheck on a per-flight basis, meaning it still will select some travelers for full screening on a random basis.

There are two ways to be eligible:

• Accept an invitation from your airline, likely only if you're a high-mileage frequent flier. Information at www.tsa.gov/what_we_do/escreening.shtm.

• Apply for Global Entry, Nexus or Sentri border-crossing passes, which can be used for PreCheck status. See https://goes-app.cbp.dhs.gov/main/goes.