Image copyright Getty Images

For most workers, telling them they can't roll into the office stinking of alcohol or high on drugs is unnecessary - because it's taken as read.

This week, though, the giant Lloyd's of London insurance market, in the City of London, is setting out a new code of conduct: it felt it needed to remind people.

The 331-year-old institution, where brokers and insurers meet to do business, is regarded as the last bastion of the financial district's boozy culture.

But after recent revelations of sexual harassment and general boorish behaviour, Lloyd's has decided to act.

Two years ago the institution banned its staff from drinking between 9am and 5pm. But this only covered about 800 direct employees.

Lloyd's is made up of thousands more people and independent operators. The organisation says there are about 40,000 pass holders who have access to the building.

Now, anyone deemed under the influence of alcohol or drugs will be barred from the building. Security guards will have the right to confiscate passes of anyone breaching the new rule.

The on-site bar will become a coffee shop. A hotline is being set up to expose bad behaviour. Anyone found responsible for sexual harassment risks being banned for life.

Lunchtime pints

But not everyone sees this as the answer.

"The problem has been exaggerated and the response is unnecessary," says a smoker loitering not too far from Lloyd's landmark building.

Tom wouldn't give his surname, and wouldn't even confirm that he worked at Lloyd's. But he certainly knew about the recent reports of sexual misconduct and the new promise to act.

Image copyright Getty Images

"You're telling people they can't have a couple of pints at lunchtime," he says. "Lloyd's is a people business. We don't operate dangerous machinery."

And yet, that there was something rotten going on inside Lloyd's isn't in doubt. Last month, the Bloomberg news agency revealed a catalogue of sexual and verbal misconduct claims, with many fuelled by alcohol abuse.

A picture was painted of an archaic institution whose culture was out-of-date, even by the standards of its neighbours in the financial district.

Lloyd's boss John Neal, who took over six months ago, called the reports "distressing", adding: "No one should be subjected to this sort of behaviour, and if it does happen, everyone has the right to be heard and for those responsible to be held to account."

The organisation knows that banning booze won't stop bad behaviour. It is, though, seen as an important signal in what Lloyd's says is a "bigger action plan" to improve the culture over time.

Although some people might argue Lloyd's is over-reacting, in the City of London there are plenty of workers who agree that the organisation needs to modernise.

In a square near the firm's headquarters, a group of young men are playing table tennis. Well-dressed, in regulation dark suits, they say they work in banking, not insurance. They point to their takeaway sandwiches as evidence.

"Lloyd's has a bit of a reputation for long lunches," says one. "A lot of that disappeared years ago in other parts of the City."

Breakfast booze

Many objections seem to focus on a resentment at being told what to do.

In a nearby pub, three men are drinking - one a large glass of wine and the other two have pints, but they're of orange juice and Coca-Cola.

"We're having a [computer] screen break - but we are discussing business. We're adults. If we drink responsibly, why should our employer lay down the law on what we do?"

There's a divide between generations too they point out: younger professionals avoid alcohol so they can go to the gym after work, or simply because they lead healthier lifestyles.

At another local pub the assistant manager agrees habits have changed in the 15 years she's worked in the trade. "I see far more men drinking soft drinks, not just at lunchtimes but after work," she says.

Image copyright Getty Images

There is still a hardcore, though, who drink. Her pub - she didn't want it identified - actually opens at 7am.

"There will be people - regulars - waiting outside at opening time to come in for a drink," she says.

Having a drink after work, perhaps? No, she says. There's a man who has a couple of pints of lager, and a woman who downs a couple of vodkas (not so easy to smell on her breath, apparently) before work. "It's more common than you might think."

These people may be functioning alcoholics, whose behaviour may not be affected by a booze ban at work. But it's not just drink, she says.

"I've seen more responsible drinking over the years, but a rise in drugs. If you don't take cocaine, people these days seem to think there's something wrong with you."

What does she think of the Lloyd's security guards who will be on the frontline of trying to impose a no drink or drugs policy?

It could be a challenge. "It's not always easy to spot, and it's not always easy to deal with when you do spot it."