Indoor smoking bans across the UK have pushed tobacco users into areas outside bars and pubs. Are these now no-go areas for non-smokers in the summer?

It's a warm, bright day, so you pick up your pint from the bar and wander outside to sit in the sunshine.

Once you step beyond the threshold, however, you're quickly enveloped by a Magnitogorsk-like fug of carcinogens.

If you're a smoker, it makes a welcome change from huddling alone in cold, rain-spattered doorways while your non-smoking friends enjoy the warmth inside.

For those averse to other people's second-hand fumes, however, it's an unwelcome reminder of the days when ingesting the emissions of fellow drinkers was largely unavoidable.

Of all the unintended consequences of the UK indoor tobacco bans enacted in 2006 and 2007, the transformation of beer gardens and outside seating areas into de facto al fresco smoking lounges is one of the most visible.

Image caption The beer garden is now the province of the smoker

The legacy of the legislation remains controversial. Supporters say it has had major heath benefits which will save taxpayers millions while opponents claim it has restricted individual liberty and hit the pockets of landlords and restaurant owners.

But members of the pro- and anti-ban factions agree that the areas outside eating and drinking establishments have become the territory of the smokers.

For most of the year the two camps don't have to mix. The vagaries of the British weather dictate smokers and non-smokers are segregated for around 10 months out of every 12.

It's not a camaraderie of the beer garden, it's a camaraderie of smokers

Problems only emerge during those rare months when the sun is warm enough for the abstainers to venture outdoors.

For some, inhaling those half-forgotten fumes can come as a shock.

"Sometimes it's like stepping out into a mist," complains Barbara Harpham, national director of Heart Research UK and a strong advocate of the anti-smoking laws.

"The majority of people don't like smoking but when they go outside it's imposed on them."

However, critics of the ban say the anti-tobacco lobby have no-one to blame but themselves.

UK smoking bans Scotland was first UK country to introduce smoke-free law in March 2006

Wales and Northern Ireland followed suit in April 2007; ban in England followed three months later

All forbid smoking in enclosed public places, such as offices, bingo halls, pubs, restaurants and cafes

Supporters of ban highlight Department of Health-funded study examining emergency admissions between 2002 and 2008 in England, which found 2.4% reduction in heart attack admissions; Scotland saw 17% decrease in year after ban, according to one report

But pro-smoking group Forest says before legislation, average of 331 pubs closed each year in the UK; in year after, average rose to 1,550

Unrepentant cigarette aficionado and Sunday Times columnist Rod Liddle, who believes the legislation should be overturned, says there is a sense of solidarity among those banished outside which makes them deeply territorial about their space.

"It's not a camaraderie of the beer garden, it's a camaraderie of smokers," he insists.

Fuelling all this is a profoundly entrenched sense of grievance, Liddle adds. "I enjoy smoking in beer gardens, standing around in public places spreading my smoke, but I'd rather go inside during the winter when it's cold."

There's little doubt that the landscape of the British pub has visibly changed since the introduction of the ban, as landlords seek to hold on to their smoking customers.

In the year after the ban in England was introduced, one brewery chain alone, Shepherd Neame, spent more than £3m building and renovating beer gardens and outside spaces, a sum of around £5-10,000 per pub.

Sales of patio heaters have reportedly doubled since the law changed.

For all that, some tobacco users feel even their status outside licensed buildings is precarious.

Liddle prefers the company of his fellow addicts. "Smokers are nicer people and more friendly. They eat and drink more, and they're more gregarious." But he expects outdoor pub smoking will soon go the way of the indoor variety.

"I assume they'll ban it sooner or later," he laments.

Certainly, smoking bans have not always come to a halt at the door of the bar or cafe.

According to the American Nonsmokers' Rights Foundation, there are bans on outdoor smoking in over 840 parks and 150 beaches and the US.

Smoking within 4m (13ft) of the entrance to licensed premises and restaurants will be banned in New South Wales, Australia, from July 2015 and Auckland in New Zealand plans to outlaw smoking in outdoor dining areas from the end of May 2018.

Academics from the University of Otago in New Zealand recommended that smoke-free areas should be extended to beer gardens and other outside areas to tackle social smoking in a 2012 report for the journal Tobacco Control.

In the UK, however, there appears to be little prospect of restrictions being tightened for the time being.

Many publicans feared a planned review of the initial legislation would extend the ban into beer gardens and doorways, damaging trade. But in 2010 the Department of Health in England said there were "no plans" to revisit the scope of the ban and the devolved governments have shown no inclination to reverse it.

It's a situation that frustrates those who would rather dine or drink in unpolluted fresh air.

"If people want to smoke outdoors they should be able to, but you don't want kids going where there are people smoking," says Harpham.

As a result, she says, families are often deterred from visiting pub gardens or dining outdoors lest those on adjacent tables set a bad example.

Her solution is for outdoor smoking and non-smoking areas. Many within the smoking lobby, by contrast, would like to see the law relaxed to allow separate zones for both sides indoors.

For now, though, the beer garden remains the province of the unreconstructed tobacco lover, and that familiar swirl of smoke will circulate around the nation's pub doorways.

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