In September 1935, the British prime minister, Stanley Baldwin published a circular entitled Air Raid Precautions (ARP) inviting local authorities to make plans to protect their people in event of a war. Some towns responded by arranging the building of public air raid shelters. These shelters were built of brick with roofs of reinforced concrete. However, some local authorities ignored the circular and in April 1937 the government decided to create an Air Raid Wardens' Service and during the next year recruited around 200,000 volunteers.
Wardens were responsible for arranged for the sounding of air raid sirens. People were now expected to immediately take cover before the raid actually started. Another siren was played to announce that it was safe to leave the air raid shelters.
The Air Raid Precautions (ARP) had the problem of dealing with unexploded bombs. It is estimated that one in ten of the bombs dropped on Britain did not explode. Wardens would arrange for all premises to be evacuated and all roads within a 600 yard radius of the unexploded bomb.
At the beginning of the war these bombs were not too difficult to deal with. The A.R.P. would inform the Bomb Disposal Unit (BDU) and skilled men would be sent to remove the fuse of the bomb. However, in 1940 the German manufacturers began to build in anti-handling devices. The bomb was now designed to explode if anyone attempted to remove the fuse. Members of the BDU therefore had the more difficult task of cutting a hole in the casting and removing the explosive contents.
The British government believed that some form of poison gas would be used on the civilian population during the war. It was therefore decided to issue a gas mask to everyone living in Britain. By 1940 the government had issued 38 million gas masks.
The government threatened to punish people not carrying gas masks. However, a study at the beginning of the war suggested that only about 75 per cent of people in London were obeying this rule. By the beginning of 1940 almost no one bothered to carry their gas mask with them. The government now announced that Air Raid Wardens would be carrying out monthly inspections of gas masks. If a person was found to have lost the gas mask they were forced to pay for its replacement.