Quality control is important and regular tests are conducted by many of the factories. The larger ones seem to run batch tests from production lines almost every evening as soon as it is dark. Some tests can also be done in the day – it really depends on the type of firework and what it is that is being tested. This is what provides the background sounds in the hills around Liuyang.

Some companies have dedicated test sites. Others, well… just watch the video and learn for yourself…

I was really fortunate to speak to the head technician of Dancing Fireworks today who explained a bit about how people train in firework manufacturing. Firework testing is a key aspect of the training.

Through my interpreter, I learnt that chemistry students from nearby Changsha initially come to the factory on a three month placement. Once they graduate, they join the company as trainees and are mentored by a more senior technician.

They start by working across the loading and production lines, to get a thorough understanding of each stage of manufacture. It’s all on-the-job training and, under supervision, the trainees are soon expected to build and test firework effects almost every day. There are industry-governed practical and written exams, especially for the more senior roles and you are expected to publish a thesis in order to become a head technician.

It takes around ten years to become fully qualified.

It is an immense industry and quite difficult to picture until I found out that there are currently 1236 firework factories in Liuyang alone.