Excessive yawning, strong body odour and arrogance are among the suspicious signs that US airport staff are trained to associate with potential terrorists, a leaked document has revealed.

A confidential security checklist used by the Transportation Security Administration (TSA), the organisation in charge of airport screening in the US, was published by The Intercept last week .

Other warning signs, according to the document , include protruding or throbbing neck arteries, whistling, excessive laughter, and "verbally expressing contempt for the screening process".

Its Screening of Passengers by Observation Techniques (SPOT) guidance, used by staff to root out potential terrorists, lists a total of 17 “stress factors”, each of which are worth one point, 15 “fear factors”, worth two points, and six “deception factors”, worth three. If a traveller scores four or more points, they should be referred for selective screening, according to the instructions.

The 17 stress factors are:

- Arrives later for flight

- Avoids eye contact with security personnel

- Exaggerated yawning as the individual approached the screening process

- Excessive fidgeting, clock watching, head-turning, shuffling feet, leg shaking

- Excessive perspiration inconsistent with the environment

- Face pale from recent shaving of beard

- Facial flushing while undergoing screening

- Faster eye blink rate when individual requested to submit to screening procedures



The TSA is in charge of airport screening in the US (Photo: Getty)

- Increased breathing rate, panting

- Obvious “Adam’s Apple” jump when requested to submit to screening procedures

- Protruding or beating neck arteries

- Repetitive touching of face

- Rubbing or wringing of hands

- Strong body odour

- Sweaty palms

- Trembling

- Whistling as the individual approaches the screening process

The 15 fear factors are:

- Bag appears to be heavier than expected or does not suit the individual’s appearance

- Bulges in clothing

- Cold penetrating stare

- Constantly looking at other travellers or associates

- Exaggerated emotions or inappropriate behaviour such as crying, excessive laughter or chatter

- Exaggerated, repetitive grooming gestures

- Hesitation/indecision on entering checkpoint

- Individuals who are seemingly unrelated but display identical dress or luggage



Negotiating a US airport (Photo: Getty)

- Powerful grip of a bag or hand inside the bag

- Rigid posture, minimal body movements with arms close to side

- Scans area, appearing to look for security personnel

- Shows unusual interest in security officers and their work routine

- Displays arrogance and verbally expresses contempt for the screening process

- Wearing improper attire for location

- Widely open staring eyes

And the six deceptions factors are:

- Appears to be confused or disoriented

- Appears to be in disguise

- Asks security-related questions

- Does not respond to authoritative commands

- Maintains covert ties with others

- Repeatedly pats upper body with hands

Points can also be deducted should certain observations make an individual less likely to be a terrorist in the opinion of the TSA. They include being an “apparent married couple with both spouses over 55 years old”, a female over 55 years old, or a male over 65 years old.

According to the Intercept, the document is not classified but has not been previously released to the public. A source “concerned about the quality” of the official guidance sent the website a copy.

Read more: Confessions of an airport security worker

Nick Trend, Telegraph Travel’s consumer editor, also expressed doubts about the advice.

“Given the stresses involved with negotiating immigration and security at most major US airports, it would be a challenge for travellers not to display several of these indicators,” he said. “I’m pretty sure the arteries on my neck were protruding the last time I queued to get through JFK.

“Trembling and sweaty palms could simply be a sign that you’re a nervous flier.”

The TSA responded to The Intercept in a statement.

“Behaviour detection, which is just one element of the Transportation Security Administration’s efforts to mitigate threats against the travelling public, is vital to TSA’s layered approach to deter, detect and disrupt individuals who pose a threat to aviation,” it said.

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