The British equivalent was the Salvus set, although the Tunnelling Companies favoured a larger version, the Proto set, which could last for forty-five minutes. In each mining sector rescue stations were established, similar to those found in civilian mines. The British appear to have been the most thorough in their rescue preparations, establishing schools in each of the Armies of the BEF at the beginning of 1916 to train officers and men in the use of the apparatus and rescue procedures. The instructors were often civilian mine rescue specialists, such as Lieutenant Rex Smart at the 1st Army School, formerly of the Dudley Mine Rescue Station.

The British in particular used animals for detecting carbon monoxide. In 1915 rabbits were most readily available and one would be lowered down a shaft to test the air before descending. Later the British used mice and canaries and each tunnelling company bred its own stocks, under the charge of an older miner. The 2nd Army instructor, G.F.F. Eagar, favoured mice, which men were trained to keep in their pockets and bring out to climb over their hands so they could more easily detect the changes in their behaviour.²⁵ Smart preferred canaries as they more readily displayed symptoms of a lack of chirpiness, panting and falling off the perch. The claws were kept clipped, otherwise the reaction to bad air was for the bird to grip the perch tightly. The clipped claws ensured that it fell to the bottom of the cage as a clear warning. However, on being brought into the fresh air the birds usually revived quickly. Mulqueen recalled an incident in 1915 which was immortalized as a cartoon in the 172 Company magazine (see below):

I remember on one occasion I was making a tour during the night shift and in one heading I found the men working, although the canary was flat on its back with its feet in the air. I wanted to know what they meant by continuing to work under such conditions and the sapper in charge expressed the view of the shift when he said ‘That bloody bird ain’t got no guts, sir’. Needless to say the shift was quickly chased out.²⁶

Men were fond of the mice and canaries, but a story was often told of the escaped canary whose presence in no man’s land threatened to warn the Germans of the presence of miners in the sector. When snipers failed to remove the bird a trench mortar was successfully employed. In exceptional cases miners would use the breathing apparatus to carry out mining tasks. The most extended use of Proto apparatus was for charging a mine at Hill 70 in September 1916, where Smart took over a mine-charging operation in order to halt a German drive that threatened to undermine the British front line. Two shifts spent a total of forty-three hours underground, each man wearing breathing apparatus for about ten hours, during which time they charged and tamped 5,000lbs of ammonal.²⁷ The most difficult rescue attempted by the British was at the Béthune collieries in September 1917. At the Fosse 8 pit the mine system extended beneath both front lines and part was still worked by French coal miners. The Germans attempted to deny the mine to the French by releasing chlorine and chloropicrin gas, which killed a number of miners and a guard from 170 Tunnelling Company. Tunneller rescue squads had to turn back 1,600yds into the mine because the gas was so concentrated that it penetrated their respirators. The medical officer to the Tunnelling Companies, Colonel D. Dale Logan, improvised gas masks from the facepieces of German masks and two British box filters.²⁸