Contents
Hiss, boom, wow – that’s how pyro shows work. So that you can show off your knowledge at the New Year’s Eve fireworks.
Are you looking forward to spectacular fireworks or are you annoyed by New Year’s Eve firecrackers? Whether you love it or hate it: behind fireworks lies ancient science and modern (craft) art. For example, did you know…
… how old are fireworks?
Nobody knows for sure, but one thing is clear: fireworks came with black powder. According to records, it was invented in China 1,000 years ago.
… what black powder is made of?
Common black powder consists of 75 percent potassium nitrate, also known as “saltpeter,” 15 percent charcoal and ten percent sulfur. So nothing out of the ordinary: Saltpeter is known as a fertilizer and occurs naturally. In black powder, it acts as an oxidizing agent to ensure that the charcoal – the fuel – can burn off. Sulfur affects flammability.
… what a “sentence” is?
Firework mixtures are called “set”. It consists of at least an oxidizer and a fuel. Black powder is still unrivaled today: stable in storage, highly flammable, robust in burning.
… that fireworks were monotonous for a long time?
Until the 19th century, fireworks sets were only made of black powder and were therefore gold and pale. Then the research duo Bunsen and Kirchoff discovered spectral analysis. Indirectly, it provided colors in the fireworks.
Now there was wild experimentation with colors, in “light sets”. But also with new materials, for new effects. Ammonium perchlorates, for example, allow combustion reactions that sometimes take place darkly and sometimes are visible. They are used for “flashing sets”.
…that black powder makes “hissing” and “boom” noises?
When black powder is burned, gas is released. This catapults fireworks into the sky. Black powder as a propellant causes the “hissing” sound.
The composition determines how quickly it burns. There is more sulfur in “delay sets,” which burn more slowly. This is how effects are timed. Only when the fireworks have reached the top should they unfold. As we all know, the “boom” comes after the “hiss”!
… how a sentence turns into a “Wow”?
Whether propellant charge, luminous charge or flashing charge – charges are almost never found in powder form. They are pressed or put into dragee form and are then called “stars”. Sentences are also combined in a star. Imagine a sphere with multiple layers. A red flashing set on the inside, an intermediate set, a green set above, black powder on the outside – voilà. In the sky we see a green glow that changes to flashing red. Wow!
…like peonies grow in heaven?
Palm trees, waterfalls, peonies or smileys – the creativity of the pyrotechnicians seems limitless. Fireworks bombs make the figures possible. “Warimono”, Japanese-style ball bombs, are particularly popular.
Different effect stars are arranged in several layers in the bombs. In between there is a decomposition charge and a delay charge so that the bomb is only detonated at the top. By the way, “Warimono” are made by hand!
… what’s all the rage?
A peony rarely blows anyone away anymore. The current art lies in creating entire fireworks choreographies to match music. Hot with the effects: quick color changes and “ghost shells”. Research is also being carried out into more ecological, low-noise and low-particulate fireworks for private use.
Legend:
ZVG
SRF Wissen: How harmful and unhealthy are fireworks?
Fritz Keller: “Wherever substances are burned, CO₂ is produced, which is also the case with fireworks. However, the amount of CO₂ emitted by fireworks is very small.” says Fritz Keller. The chemist and pyrotechnician works for the Pyrotechnic Industry Association in Germany and has investigated the influence of fine dust emissions on air quality.
Where should and can fireworks become more ecological?
“Especially when it comes to fireworks that are set off by private individuals, i.e. small fireworks, there is a desire and potential to become more environmentally friendly. An initiative has been launched in Germany to completely ban plastic from these fireworks. There are still a few plastics around – especially where it is relevant to safety. We’re trying to gradually replace that with cardboard and the like. The EU has taken on this initiative, including Switzerland.”
And how dangerous are fireworks to health?
“100 years ago, highly problematic substances were still used: mercury, arsenic and antimony, for example. Of course people have become smarter here. And there are also corresponding laws. Barium salts are still dangerous today; they are used in the production of green sentences. However, they are only dangerous in production and must not be inhaled. As soon as they burn, barium carbonate and barium sulfate are formed. These substances are no longer water-soluble and are not toxic to the environment or to us.”
And the fine dust?
“Pyrotechnic objects all produce a certain amount of fine dust. During large fireworks displays, i.e. at heights, it is usually distributed quite well and quickly. Private fireworks displays on the ground often occur in many places at the same time. There are definitely high peaks in fine dust concentrations. All types of particulate matter are considered equally problematic, and that may not be entirely true. I don’t want to trivialize this, in principle you shouldn’t inhale smoke, it always has an irritating effect. The fine dust particles from fireworks are often soluble salts – black powder, for example, produces potassium sulfate – which is transported away by the lung fluid and is therefore more harmful than soot particles from diesel engines, for example.