How do safety matches differ from normal matches

A. There are two types of matches: safety matches that need a special striking strip to ignite and matches that you can light by striking almost anywhere.

The difference between the two is down to their different chemical composition and reactions.

Q. How do safety matches work

A. Safety matches are made 'safe' because all the various elements required to ignite them are kept separate and are only brought together when the match is struck against the safety strip.

Normally a match head is made of sulphur, an oxidising element and phosphorus. When the match is struck against a surface the friction creates enough heat to set off a chemical reaction that ignites and combusts the head.

However with a safety match these combustible chemicals are kept separate. The match head contains an oxidising element and sulphur. Alone these two cannot ignite using normal friction, making the match safe. This is where the safety strip comes in, it contains the extra essential element: phosphorus. It is only by combining these elements, i.e. striking the safety match against its special striking surface, that it's possible to combust the match

Q. How long have normal friction matches been around

A. Phosphorous, the all important ingredient was discovered in 1669 and in 1680 an English physicist named Robert Boyle coated a small piece of paper with phosphorous and coated a small piece of wood with sulphur. Although he succeeded in creating a flame by rubbing the two together he didn't come up with a useable match like product.

It wasn't until 1827 that John Walker, an English chemist and apothecary, came up with something that resembled the modern match. But he failed to patent his design and made very little money from his invention.

Q. Are safety matches a much more recent invention

A. Not really. Johan Edvard Lundstrom of Sweden patented them in 1855 when he put the phosphorus on the sandpaper outside the box rather than combining it with the other chemicals on the match head.

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by Lisa Cardy