Image caption A number of factories have now been turned into call centres

More people than ever before work in call centres in the UK but are they the modern-day equivalents of the factory production line?

The chimney of the India Mill factory in Darwen, Lancashire, still stands today. When it was built in 1867, it was the tallest and the most expensive in the country but its shadow now falls over office space rather than the industrial machinery it used to.

This is a scene that has become increasingly common across the UK as the service industry expands across what William Blake once described as this "green and pleasant land". At the same time, the manufacturing industry has contracted sharply.

Immediately after World War II, manufacturing accounted for around 40% of the UK economy's output but now only 8% of jobs are in the manufacturing sector, according to the Office for National Statistics.

At the same time, the rise of the call centre - known in the industry as contact centres - has seemed unstoppable.

'Toilet monitor'

"More people have worked in call centres than ever worked in the mining industry, and I researched that in 1998," says Matt Thorne, who wrote a novel based on his experiences in a call centre.

"The interesting thing about call centres is they're great if you've got something else but it's like a proper job without any of the benefits.

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"You got four 15-minute breaks in a day and the amount of time you spent in toilets actually was monitored."

Over one million people are employed in contact centres, according to analysis firm ContactBabel. This is over 3.5% of the entire UK workforce.

When call centre pioneer Direct Line opened its lines in Croydon, south London, with 63 employees on 2 April 1985, no-one could have imagined the impact it would have on the UK's service industry. In 2004 it received over 22 million phone calls.

But many just see them as a nuisance. Time and time again, call centres have been voted one of the most frustrating things to use, with one survey even concluding that calling one is more stressful than getting married or going to the dentist.

"They were predominantly set up as a way for companies to save money - whether the customers liked it or not," says Ann-Marie Stagg - chairwoman of the Contact Centre Managers' Association.

You don't hear about workers having to put their hand up to go to the toilet anymore Steve Morrell, Indusry analyst

And if just phoning up a call centre was stressful, imagine working with a pre-determined script and repeating it day after day.

"The aim was to get everything done in 35 seconds, so there's not really a lot of room for warmth," says comedian Andy White, who worked in a call centre until 2002.

"The bonus system was very difficult because part of it was based on the people around you so people were thinking 'why should I bother?' when it only takes one person to not turn up for the figures to suffer and then there goes my bonus."

It is this perception of call centres, as a telephonic battery farm with repetitive work like factories from generations ago, that the industry is desperately working to change.

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The highest percentage of workers in call centres are in Scotland, the North East, Yorkshire and the North West - traditionally the industrial towns of old. Over 5% of all workers in these areas are working in call centres. The lowest percentage is in London.

"You hear a lot of nonsense about why call centres started up where they did - accents and stuff like that," says Steve Morrell, of ContactBabel.

"But that's nothing to do with it at all. It's all to do with a cheap, available labour force."

'Satanic mills'

Call centres are classic targets for mockery. In the film Big Nothing, David Schwimmer's character Charlie is placed in the "Jennifers and Stephens" section of a call centre because "callers like to think they get the same service rep".

A criticism regularly voiced is the "quantity over quality" set of statistics by which workers are measured. Often, a certain number of calls have to be answered by each member of staff per hour, in the same way as factory workers are sometimes paid per item they produce. But industry figures deny this.

"All that would happen is the adviser would talk faster so no-one could understand them or they'd just cut the customer off," says Stagg.

Image caption Call centre managers increasingly believe it is how to work better rather than faster that is important

"It's all a vicious circle. The customer would just ring up again and be more upset. It took a while for the industry to work that out."

But, Stagg is keen to point out, call centres have changed.

"These places used to be dark satanic mills but the industry really has got its act together," she says.

Around one third of call centre staff now have a university degree, and conditions are improving.

"You don't hear about workers having to put their hand up to go to the toilet anymore," Morrell says.

Universities are even offering MSc courses in contact centre management and average pay for workers is increasing.

"I don't think anyone sets out to work in a call centre because they're interested in it," says Stagg.

"Most people that come in see it as suiting their hours or go in there for a couple of years before they move on. What takes some people by surprise is that there is a career path - and you can move from the call centre into different parts of the business."

Perhaps then, unlike the factories of old, ambitious workers will not be stuck on the shop floor for long.