How big is Matchstick? | Scale of the Universe

A matchstick is a thin stick, usually of wood, tipped with a head of chemicals that bursts into flame when it is struck. The match in the explorer is 5 centimeters (2 inches) long, from the tip of its head to the end of the stick. Match standards set a minimum length rather than an exact one: two regional standards require box matches to be at least about 4 centimeters (1.6 inches) long.

Size

Match standards describe the stick, called the splint. The safety-match standards of the East African Community and of CARICOM, the Caribbean Community, both require box matches to be at least 40 millimeters long. The stick must be at least 1.9 millimeters wide and thick. Matches in the same box may not differ in length by more than 2 millimeters.

Book matches, which sit in rows inside a folded cardboard cover, have their own rule. Each must be at least 35 millimeters long, or 45 millimeters including the shared base it is torn from. The standards set no maximum length, and the explorer's 5-centimeter match meets both minimums.

Size comparisons

The match is a little shorter than a large chicken egg, the next larger object in the explorer, which is about 6 centimeters long.
It is about twice as long as each side of a square inch, which is 2.54 centimeters.
About six matches laid end to end would span a 12-inch (30-centimeter) ruler.
A box-match stick, at least 1.9 millimeters thick, is as thick as about 20 human hairs laid side by side.

How a safety match lights

There are two main kinds of match. A strike-anywhere match lights when it is rubbed on almost any surface. A safety match lights only when it is struck on the special strip on the outside of its box or book.

A safety match splits its fire-making chemicals between the head and the strip. The head holds potassium chlorate and sulfur, among other ingredients. The striking strip holds red phosphorus and antimony sulfide. The match is designed not to light easily unless its head is struck against that strip.

What the standards test

Standards check that a match lights at once, burns properly and goes out safely. Under the Caribbean standard, its flame must reach at least 10 millimeters high and burn for at least 10 seconds, or 6 seconds for a match shorter than 40 millimeters. The flame must spread from the head along at least a third of the stick, and no more than 5 percent of heads may explode or drop hot ash.

Box-match sticks are soaked in chemicals so that they stop glowing once the flame is out. A stick may keep glowing for no more than 3 seconds.

The first friction matches

John Walker, a pharmacist in Stockton-on-Tees, England, made the first practical friction matches, which light by being rubbed. His day-book records his first sale of them, on credit, on April 7, 1827. The customer, a Mr. Hixon, bought 100 of his "Friction Lights" and a tin case to keep them in.