LONDON — Debrett’s, the publishers of a famous handbook on social skills and manners, has released a new guide to modern-day etiquette.

For the first time in its 245-year history, the authority behind the 480-page guide has shared the most frequently asked questions submitted by the public, and published some pointers in response.

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Debrett's receives over 10,000 enquiries a year, suggesting that a more permissive and modern existence, free of Downton Abbey-like constraints but driven by technology, is rife with dilemmas.

Editor Jo Bryant told Good Morning Britain: “I think it really shows that as we live in a more relaxed society, the rules are less clear.”

“In years gone by, generations knew what was expected of them and it was much more rigid, whereas now that fluidity has actually created more confusion.”

Should you apply makeup on the tube? Is it OK to vape at work? Is reclining your airline seat acceptable?

It's a minefield out there, and their pointers aim to answer those questions definitively.

Phone use

Among the agonised enquiries, mobile phone use is one of the hottest topics. Debrett’s insist your phone must be switched off in theatres, cinemas and galleries, and put away when you’re paying for something in shop.

Jo Bryant explained further: "The rule is that you should always give the other person more attention than technology. It’s incredibly rude to prioritise your phone over the person you’re dealing with.”

Email

Debrett’s take umbrage at blind copying. While CC’ing half the office on banal emails seems to be OK, they deem a BCC “deceptive,” insisting that “blind copying should be used discerningly."

"Instead the email should be forwarded on to the third party, with a short note explaining any confidentiality, after its distribution."

Greetings

When should you kiss someone? Only among friends and not on the first meeting, apparently.

“An air kiss, without contact, may seem rude or impersonal, so very slight contact is best but no sound effects are needed,” they insist. So steer clear of the “mwahs.”

E-cigarettes

The rules here are simple: “Vaping shows that you’re not focused on your work and may also be a distraction to your colleagues.”

Public transport

Some of their advice is basic common sense — vacate your seat for the elderly and the pregnant — while other tips are somewhat more open to debate.

The controversial Women Who Eat On Tubes site, which aimed to shame people eating underground, and a subsequent protest picnic, highlighted what a divisive issue snacking on the move can be.

Debrett’s wades in to the debate, declaring, “it’s inconsiderate to eat smelly food in a confined environment.” They also attempt to settle the issue of applying make-up on the way to work, suggesting that it makes you look “disorganised.”

Flying

In answer to the age-old debate about reclining your seat: the official line is it’s selfish and should be avoided, during short daytime flights at least. Hogging the armrest is also a no-no.

Image: Getty Creative, Herbert Kratky

Eating

You should wait until everyone is served before starting, but you knew that already, right?

Debrett’s dates back to 1769, when it began advising Britain’s ruling class from its Mayfair headquarters in London. Mentioned in works by Oscar Wilde, George Orwell and P.G. Wodehouse, it’s long been established as the final word in etiquette.

However, much of its advice is somewhat distant from everyday concerns. Its guide covers everything from how to wear a kilt to how to serve port, among "tables of precedence" for ladies and gentlemen and tips for addressing the queen.

At least now they’ve turned their attention to some of our more pressing concerns.