Millions of people will be in transit in the coming weeks over the busy Easter travel period, including thousands of Irish holidaymakers jetting abroad.
While there are a number of measures to consider, such as Covid restrictions, passport validity and airline rules, there are other less well-known factors to be aware of.
According to one travel expert, there are four letters that no passenger will want to see on their boarding cards when at airport security.
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In a video on TikTok, they explained how what the letters SSSS mean when printed on the boarding passes and why they could spell bad news.
The expert explained the four S's stand for 'Secondary Security Screening Selection' and mean that you could face some additional airport security checks before jetting off.
The video also revealed that the letters mean officials will likely give you a pat down in order to check for any security breaches, as the Daily Record reports.
Additionally, the extra checks include swabbing for explosive residue as well as opening up all of your bags to perform a thorough check.
The travel expert, named Michelle, explained: “This is something you never want to see on your boarding pass: The quadruple S.
"It means you’re going to get searched super thoroughly, and it’s usually found on international flights to the US."
The majority of passengers with the SSSS on their boarding passes are picked at random.
However, those with the code on their pass are likely to be monitored by the US Department of Homeland Security.
Michelle explained how to fix the problem, saying: “If you go to the US Department of Homeland Security website, you can apply for a redress number which prompts the DHS to review your record and clear up any erroneous or weird info that could be triggering the additional security measures.
“Once they’ve investigated your records and you’re hopefully cleared, you’ll want to input your redress number on all of your flight reservations going forward, and you should hopefully be good to go.”
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