An Abyssinian soldier wearing a gas mask during training at Addis Ababa in preparation for an expected poison gas attack by the Italians in the Italo-Abyssinian War. (Photo by Keystone/Getty Images). 26th October 1935

Men wearing gas masks exercising in a factory yard. (Photo by General Photographic Agency/Getty Images). Circa 1935

Men wearing gas masks carry a man out of a door reading “Not Ausgang”. (Photo by General Photographic Agency/Getty Images). Circa 1935

Able seamen at the Royal Navy Anti-Gas School at Tipnor, Portsmouth play ball games wearing gas masks, to accustom them to carrying out strenuous tasks in respirators. (Photo by William Vanderson/Fox Photos/Getty Images). 22nd January 1934

Able seamen learn how to cope with gas warfare at the Royal Navy Anti-Gas School at Tipnor, Portsmouth. (Photo by William Vanderson/Fox Photos/Getty Images). 16th January 1934

Royal Marine recruits practising trench warfare in their gas masks. (Photo by William Vanderson/Fox Photos/Getty Images). 10th March 1933

Nurses wearing gas masks attend to a patient, during a gas attack demonstration held at Toynbee hall, London, by the St John Ambulance Brigade. (Photo by A. Hudson/Topical Press Agency/Getty Images). 28th September 1935

Sailors fitting gas masks on to visitors at Chatham, England, where a rehearsal is being held in preparation for the opening of Navy Week. (Photo by H. Allen/Topical Press Agency/Getty Images). 1st August 1935

British soldiers wear gasmasks during manoeuvres. (Photo by Fox Photos/Getty Images). August 1928

Pest control men in gas masks spray insecticide around Winchester Cathedral in an attempt to exterminate an infestation of death watch beetles. (Photo by Fox Photos/Getty Images). July 1935

Labour supporters electioneering in gas masks and carrying sandwich boards saying, “Vote Labour. The Labour Policy is Peace and Prosperity”. (Photo by Fox Photos/Getty Images). November 1935

A soldier escorts two young visitors to the gas chambers during an open day at Kingston Barracks in Surrey. (Photo by Keystone/Getty Images). 29th June 1935

Air Raid Precautions Department of the Home Office testing a portable siren at Hendon. (Photo by William Vanderson/Fox Photos/Getty Images). 10th March 1936

Two fire fighters emerging from a smoke-filled vent. (Photo by Keystone/Getty Images). 30th August 1929

Workers testing safety equipment in a German factory, part of a military Rearmament programme. (Photo by Keystone/Getty Images). Circa 1935

A fire-fighting class being given by the Brighton Fire Brigade. (Photo by Fox Photos/Getty Images). 7th February 1934

Portrait of the chief of the Calais Fire Brigade, Captain Edouard Vigne, inspecting the British Fire Brigade, during the national life saving competition in Hastings. (Photo by Fox Photos/Getty Images). 28th July 1935

Scots Guards trying on their gas masks before sailing to China. (Photo by E. Bacon/Topical Press Agency/Getty Images). 7th April 1927

A gas mask and a diving mask being demonstrated at the 10th Engineering & Machinery Exhibition at Olympia, London. (Photo by Topical Press Agency/Getty Images). 1929

Three workers demonstrating the different types of gas masks used in mine rescue work. (Photo by Fox Photos/Getty Images). December 1925

A canary in a glass fronted box is being used to test the toxicity of gas inhaled by a mine rescue worker. (Photo by Fox Photos/Getty Images). December 1925

A fireman rescuing someone from a building during a gas mask class for London firemen. (Photo by Fox Photos/Getty Images). April 1928

A mine rescue brigade fully equipped with breathing apparatus. (Photo by Steele/Fox Photos/Getty Images). 22nd September 1934

A selection of breathing apparatus on show at the Shipping and Engineering Exhibition at Olympia in London. (Photo by General Photographic Agency/Getty Images). Circa 1930

On manoeuvres armed German soldiers are wearing gas masks and riding motorcycles with side-cars. (Photo by General Photographic Agency/Getty Images). Circa 1936

Three girls modelling various dustbowl masks to be worn in areas where the amount of dust in the air causes breathing difficulties, circa 1935. (Photo by Bert Garai/Keystone/Hulton Archive/Getty Images)