Safety & accidents

Making sure explosives don't explode…
until you want them to

 
 
Accidents didn't happen often, but when they did they caused massive damage and loss of life. Factories were designed to operate as safely as possible.
 

At Pitsea explosives factory you were searched on your way into work. Anything that could make a flame or spark had to be left at the gate.

You were searched again as you left to make sure no explosives found their way out of the factory.

The Women’s entry search prevented anything that might cause a spark coming into the factory.

Minimising the risks

Wooden walkways around the factory stopped your shoes picking up stones from pathways, as the stones might cause a spark.

Tracks were laid to eliminate bumps 

Works overalls had no pockets. They were different colours according to your job so you could only access areas you knew enough about to work safely in. If there was an accident the colours helped the head count to see quickly who was missing in which area.

Factories were built in remote places to protect nearby villages and towns. Buildings and the landscape around them were designed so that an explosion in one building wouldn't blow up the others. Dangerous materials like Nitro-Glycerine were moved around the site on rails to avoid bumps.

Accidents in the factory and the laboratory

On 28th March 1913, three men died and others were injured in an explosion in a guncotton drying stove at the Pitsea factory.

The official government report (reproduced here thanks to the Chiaraviglio collection, Florence) covers the incident in great detail, and presumes some carelessness but blames nobody. An alternative theory suggests both explosions could have been caused by a faulty batch of guncotton from Ardeer, part dried there and part shipped down by sea to Pitsea.

In May 1916, a chemist and his assistant were killed in a laboratory at Pitsea when the chemist dropped a small bottle of Nitro-Glycerine. This letter from the Ministry of Munitions of War (from the National Archives) is a ministry official's report on the incident.

Download a PDF of the report (3.3 MB) here. Opens in a new window.

Blast Mounds

Dangerous areas in the factory were kept apart by heavy mounds of earth with steeply angled sides. These were called blast mounds.

They were designed to deflect the force of an explosion upwards into the air instead of letting a blast carry on sideways into another building.

The remaining blast mounds from the Pitsea factory can still clearly be seen all over Wat Tyler Country Park.

An RAF aerial photograph from 1953 clearly showing buildings and blast mounds all around the site.

An RAF aerial photograph from 1953 clearly showing buildings and blast mounds all around the site.

The blast mounds at Wat Tyler are far more than landscaping.

Mixing Nitro-Glycerine

Highly unstable nitro-glycerine was the main ingredient of explosives made at the Pitsea factory.

Making nitro-glycerine was very dangerous. Concentrated acids were mixed with glycerine in huge vats. If too much glycerine was added too quickly to the mixture, it would become unstable, and a large valve would have to be opened to quickly dump the whole batch into a large vat of water. Failure to do this quickly could have led to a catastrophic explosion.

Mostly, though, the process was very dull. The operator would sit at the mixing machine for long hours just looking at the dials to make sure the machine was working OK, and there was a good chance they could fall asleep on the job. A one-legged stool made sure they had to perch to stay awake. At Pitsea it seems this was very effective, because in all the years the factory operated they never once had to dump the Nitro-Glycerine mixture.

Mixing nitroglycerine for hours on end was deadly dull. A one legged stool made sure the operator didn't drop off on the job.

Mixing nitroglycerine for hours on end was deadly dull. A one legged stool made sure the operator didn't drop off on the job.