World War One: Avonmouth gas factory safety 'secondary'
Poison gas was one of the most hated and feared weapons during World War One. But it proved just as dangerous to the workers in the factories where the gas was manufactured and put into artillery shells.
"Gas! Gas! Quick, boys! - An ecstasy of fumbling, Fitting the clumsy helmets just in time; "
Wilfred Owen's famous war poem, Dulce et Decorum Est, graphically sums up the ordinary soldier's loathing of poison gas.
But mustard gas was just as dangerous to those manufacturing it.
At a factory on the Chittening Industrial Estate in Avonmouth, near Bristol, three workers died and 65% of the workforce suffered gas-related illnesses in one seven-month period alone.
So great was the problem, the factory even had its own hospital.
The factory's medical officer, Capt HM Roberts, admitted in a report written at the end of 1918 the safety of workers was a "secondary" concern compared to the "urgent" need for supplies of the deadly blistering agent.
Peter Insole, archaeological officer for Bristol City Council, said the Germans had already "perfected" the production of mustard gas and the British were trying to catch up technologically.
"What we do know about Britain's production of mustard gas is that we actually caused more casualties producing the stuff in this country than we did on the front, which is a crazy statistic really," he said.
In the seven months from June 1918, three workers died and 710 out of the 1,100 employees were injured.
In his report, Capt Roberts makes no secret of the dangers.
The "urgent demand" for supplies meant production took priority over safety and the protection of workers at the plant was given "a somewhat secondary position", he wrote.
"The difficulty, not to say hopelessness, of taking adequate measures of prevention in the manufacture of [mustard gas] can perhaps only be fully understood by those who have actual experience of the process."
He also noted dealing with "80 or 90" cases a day left "little time to consider methods of reducing casualties".
Fumes from the chemicals, which were heated to make the gas, caused inflammation of the eyes and bronchitis.
Chronic symptoms recorded at the hospital included "mental inertia" and "memory weakness".
Mustard gas was designed to cling to clothing and could survive for long periods as a dangerous liquid.
As a consequence, many of the injuries to workers happened when they were changing pipes or cleaning machinery.
The factory tried to deal with the problem of workers breathing in dangerous chemicals by setting up what Capt Roberts called a "very elaborate system of ventilation".
Workers were also issued with helmets, overalls and rubber boots, but these too failed to protect them.
Towards the end of 1918, the factory experimented with protective clothing treated with duroprene, which was far more effective.
Capt Roberts highlights the cases of two workers who were sick for more than a month after changing a pump at the plant.
"Not one of these cases would have occurred if the duroprene clothing had been used," he admitted.
The dangers inherent in working at the plant led to the introduction of a special leave system, according to Mr Insole.
"[Workers] actually earned a day's leave for every 20 days working, just simply because they recognised that the amount of hours they were doing on this site was actually making them ill, " he said.
Put bluntly the British "weren't very good" at making mustard gas, he said.
The Hague Conventions of 1899 and 1907 outlawed the use of "dangerous chemical agents" in wars, but after the first poison gas attack by the Germans at Ypres in 1915, both sides began developing and using increasingly deadly types of gas.
Mustard gas was one of the final products of that arms race. It caused blisters that could blind and damage lungs badly enough to kill.
British mustard gas was manufactured at Avonmouth and put into artillery shells at National Filling Factory number 23.
'Legacy of war'
The factory made just over 400 tonnes of the gas between 24 August and 11 November 1918 - Armistice Day - when production ceased.
Only a few single-storey buildings still survive of the factory, along with the railway lines that served it.
According to Mr Insole, its deadly product did have one positive effect - it was a factor in the number of chemical firms, including ICI, that went on to set up plants at Avonmouth.
"This is the legacy of World War One - what you see now is a result of the decisions made in 1914," he said.
One less welcome legacy was the need for chemical experts from Porton Down to check the land where the mustard gas factory stood before it could be redeveloped in 2012.
- Discover the horrific side effects of developing mustard gas and find out how you fix a face that's been blown off by shrapnel with Michael Mosley.