Travellers have been ordered not to look too happy in their passport photographs to avoid confusing facial recognition scanners.
Toothy, open mouthed grins are being outlawed from the tiny 35mm by 45mm photographs because they will throw off scanners used at airports.
Long fringes and head coverings, are also banned, under the new regulations along with dummies in babies' mouths.
The new type of passports are being introduced in a bid to fight terrorism.
A Home Office spokesman said: "When the mouth is open it can make it difficult for facial recognition technology to work effectively."
The machines work by matching key points on the holder's face, such as the mouth and eyes, with the photograph.
It is easier for it to recognise a neutral expression with the mouth closed.
Chief executive of the UK Passport Service (UKPS) Bernard Herdan said: "These new guidelines are an important step in the development of the new biometric ePassport and use of facial recognition technology that will be introduced in 2005 as part of the ongoing fight against fraud and international terrorism."
The UKPS is planning to implement a facial recognition image biometric in the British passport book from late 2005 to early 2006.
It is hoped the biometric image will help to counter identity fraud and verify the identity of the holder against the document.
The new rules say "photographs must show no shadows: your face looking straight at the camera, a neutral expression, with your mouth closed."
Eyes must be open and clearly visible, and there must be no sunglasses, tinted glasses or hair across the eyes, it adds.
Anyone who wears glasses must wear them at the end of their nose so they do not cover their eyes. They must also ensure the lenses do not produce reflections.
No head coverings are allowed unless they are worn for a religious belief.
The new photographic regulations are effective immediately but the Passport Service says it will exercise some flexibility until early 2005.
Existing passport holders will not need to have their current passports updated, but they will have to comply with the new guidelines when they renew their passports.
Would your passport pic pass muster under the new rules? Why not send us your comments - using the form below- or send your passport photo and comments to email@example.com
It's simple; if these new computer systems can't do the job properly, let alone as well as a human can already do it, then they're not ready and should not be used yet.
Why should we change our behaviour to compensate for an inadequate, unnecessary and expensive computer system?
Duncan Corps, Knebworth, England
My passport will be fine, but reading the do's and don'ts for children's passports is ridiculous. As if a young toddler/child is able to be a terrorist. This is getting absurd. Yes they should tighten up on pictures, but surely not for children. I had loads of problems getting my child to have her photo taken at 13 months old, sounds as though I will have many problems with my 9 month old twin boys.
Michelle, Rainham, Kent
My passport photo has a picture of me from 1996 with very long length hair, a beard and a scruffy t-shirt.
Bearing that in mind, the last time I got on a flight I was wearing a suit - the hair and beard have been chopped. No one took a second look at the photo...
John, Southampton, UK
Why was none of this deemed necessary when the IRA was waging a terrorist war against us?
Matthew Hunt, Felixstowe
I recently applied for a passport renewal. I was told that my chin was too dark in the photo I submitted (I am black) and that the scanning software could not lighten the it sufficiently for it to be of use!
Paul Ashman, Bromley, Kent
Oh, well done! Millions of pounds spent on a system that cannot deal with one of the most basic human expressions. There can't be much hope therefore for it dealing with people gaining/losing weight, growing/removing facial hair or indeed aging by 10 years over a 10 year period.
Richard, Harrogate, UK
As far as I know, it has always been the case that passport photos are not supposed to show you smiling. In fact, Norman Wisdom used this very instruction for a scene in his film "Man of the Moment". This is certainly the advice I've always seen in the application forms, and it is what I have always complied with. So yes, my passport photo would pass muster under these rules.
David Hazel, Fareham, UK
I assume that Blunkett will now be passing a law forbidding smiling, babies dummies or any type of facial covering in airports in order for the technology to work properly.
Adam Naylor, Kidderminster, UK
If you look like your passport photo, you are too sick to travel!
Malcolm, Milton Keynes, Bucks
The technology for facial recognition is massively over hyped. In fact it is extremely unreliable even under ideal conditions. This story is just an early indication of the fact that the technology is not even close to working well enough for this application. Yes a digital image can be stored on a passport, no a machine will not be able to tell whether a person matches the photo any better than a human could and in fact will do worse.
Alan Johnson, Thame, UK
Should not be a problem - with this increasingly nanny state, we have nothing left to smile at anyway !
Neil McDougall, Marlow England
Why on earth are people whinging. It doesn't matter what the reasons are for passport photos being what they are.
The Passport Office sets the rules. We have two choices: follow them, or don't get a passport. After all, leaving the country is not compulsory!
John Smith, London, UK
I welcome any system that can be used to identify potential terrorists. A human cannot remember the faces of all suspects. Even if a computer only recognises a few faces, this could potentially avoid another terrorist atrocity.
Simon Rowan, London
To me photos of young children seem pretty pointless anyway. My sons passport has a picture of him taken by the hospital photographer when he was just a few hours old, but it's valid for 5 years. At 20 months he already looks nothing like the photo, and even though it would obey the rules on no smiling and so on, can you really tell me that a scanner will be able to make a match between photo and child when he is 4 or 5 years old?
Rob, Dorchester, UK
In response to Matthew Hunt of Felixstowe's question, I would guess this has more to do with the unreliability of face recognition technology than with the seriousness of the threat. As a technology it has a lot of appeal for people who work in border control and national security, because it promises the possibility of scanning large numbers of people very quickly for any of a number of 'wanted' faces. But as yet the technology is still in its infancy, and can be thwarted by hats, glasses, beards, etc. and evidently even a smile. Close your mouth on your passport photo and smile on your way through customs though, and the effect will presumably be the same.
Bruce Ashton, Reaing, UK
Glasses at the end of my nose - and a po face? Evidently the intention to make all focally challenged persons look like vicars in their passports is a device to conceal the true identity of some fanatical religious terrorist outfit. We must beware - some deep radical Anglican organisation has obviously infiltrated the passport office. Just because you're paranoid, don't mean they're not after you!
Andy Mayo, Cambridge, UK
I once sent a photo in so that they could process my new passport and they sent it back saying that the photo was unacceptable because the top of my head reached the top of the photo. I sent in a clipping of my hair and asked them to attach it to the photo... they weren't amused.
Richard Johnson, London
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