THE strange contraption which loads of people spotted on the roof of Darlington Covered Market in Memories 279 was an air raid siren.

It was probably a hangover from the Second World War, but it was maintained throughout the Cold War so that it was ready to sound the Four Minute Warning when Russia had launched a nuclear ballistic missile.

To anyone who lived through the Second World War, or the Cuban Missile Crisis of 1962, its wail must have been truly terrifying. Those lucky enough to have been among the peacetime generation probably regard it as the quirky noise at the end of Dad’s Army.

From 1957 to 1992, the sirens were under the control of the UK Warning and Monitoring Organisation, although much of the ground work was done by the volunteers of the Royal Observer Corps (ROC).

Word would come from listening posts, like Fylingdales on the North York Moors, that therer were inbound missiles coming from Russia, and the organisation would take control of the radio and TV airwaves, and set off the sirens.

The sirens were usually placed on the top of tall buildings, or on public buildings, like police stations and post offices. A lot were on pubs – how many pub cellars have an obsolete air raid siren in them?

Nationwide, there were 7,000 electric sirens, like the one on the market roof, and they were connected to the telephone network and would go off automatically when triggered by the warning organisation.

There were also 11,000 hand-powered sirens in more remote places. Usually postmasters would operate these, although ROC members also played a part.

The sirens emitted two types of wail: the long rising and falling wail, which indicated a raid was imminent, and the single note wail, which meant “all clear”.

“I remember the siren was tested infrequently – at most once a month – even into the 1970s,” says David Oliver. “It would send a chill down one’s back –the Cold War was very evident in those days, and the Cuban Missile Crisis was not such a distant memory.”

Dave Middlemas, of Merrybent, got to perform the testing of the siren that was housed under a louvered wooden cover on the roof of Durham Cathedral’s tower.

He says: “As a policeman in the 1980s, it was part of our ‘War Duties’ to test the sirens on a monthly basis by performing a ‘Flick Test’. This involved briefly switching them on and off (ie ‘flicking’ the switch) – sufficiently to be able to only hear the beginnings of a drone as the siren began to pick up pace for a second or two. For this reason most of the public would be unaware that they were being tested or even that they still existed.

“Flicking for the cathedral siren was performed via a switch located within the tower but it did still involve climbing many of the stairs and was not a popular task.

“I’m a little ashamed to say that by this stage, peacetime complacency had caused the testing to be regularly overlooked.

“Murton colliery had a siren into the 1980s and the police had come to an arrangement that they would telephone a request to the pit to have the siren ‘flick’ tested by colliery staff. Their idea of ‘flicking’ could be somewhat longer than those of Durham Constabulary however (perhaps tinged with a little be-devilment!) and the siren could on occasion crank up fully for a minute or two!”

So, if Murton colliery had a siren, where else were they positioned?

Maureen Green wrote to say that in Darlington there were sirens on the North Road shops and on the Cleveland Bridge works in Smithfield road – this one was used into the 1960s to announce that it was finishing time.

Anthony Magrys remembers that there was a siren on the police house in Lanethorpe Road, Darlington, which was tested occasionally during the early 1960s.

Another Darlington siren, according to Dennis Harrison, was on a tall pole in the rear garden of the police house in Coleridge Gardens, and it, too, was tested into the 1960s.

Dave Stevens in Byers Green writes: “There was one on Coxhoe secondary modern school, which has now been demolished. It was right out the back of my grandparent’s house in Victoria Terrace. They tested it now and again and it was deafening.”

Schools were obviously popular places for sirens as Peter Daniels of Bishop Auckland remembers that soon after he started teaching at St Helen’s Auckland School in 1966, a siren was installed at the end of the playground marked “Girls”.

“The siren was tested annually, but it never really got up to speed in case people thought the end was nigh,” he says.

The thawing of the Cold War and the growing popularity of double glazing marked the end of the air raid siren – the Government said the sirens were losing their effectiveness because double-glazed residents could no longer hear them.

Because of the improving global security picture, the UK Warning and Monitoring Organisation was wound up in 1992 and the ROC was stood down at the end of 1995. Sirens began to disappear at the same time, although the Covered Market siren probably went earlier.

It was placed on top of the council chamber which in the 1920s was somehow constructed inside the roofspace of the market building. When the Town Hall in Feethams was completed in 1970, the Covered Market was expensively overhauled, and we’ve never seen a post-overhaul photograph which has the siren in situ.

Not that the sirens have been completely eradicated from our soundscapes. Several people got in touch from Newton Aycliffe to tell us about the siren on a chemical factory which is tested at 10.45am every Thursday morning, so that if there is a toxic chemical leak, people can be quickly alerted to stay indoors with their windows shut.

This, we believe, is the last of the sirens.

But can you tell us where any other sirens used to be located, and it would be magnificent if someone – perhaps in a pub cellar or on a cathedral roof – still has a decommissioned siren that they could show us.

And then there is another query raised by David Oliver. He says: “Some people in the 1960s and 1970s built nuclear fallout shelters on their private property. These were kept as secret as possible to avoid the public storming them when the four minute warning went off!

“I doubt many would have been built but there was always a rumour about one at a certain house in Hurworth.”

So who can tell us about nuclear fallout shelters, and was there ever one at Hurworth?

BLOB With thanks also to Anthony Crooks, Bryan Folkes, Andrew Angus of Neasham, David Balls and Wally Mellors, among others, for their contributions to this article. We mentioned the ROC last year in Memories but never got round to producing a list of their nuclear-proof bunkers – we’ll try and come up with one in the near future.