Matches are a common household item, used for various purposes. These small tools are classified according to specific safety standards for safe handling and transportation. Understanding their hazard classification helps recognize potential risks and implement appropriate safety measures. This system protects individuals, property, and the environment from potential dangers.
What Are Hazard Classes?
Hazard classes are a standardized way to categorize materials that pose risks during transport, storage, or emergency situations. These classifications are based on the inherent physical and chemical properties of a substance. International frameworks, such as the United Nations (UN) Recommendations on the Transport of Dangerous Goods, provide a global basis for these categories. National regulations, like those enforced by the Department of Transportation (DOT) in the United States, adopt these principles to regulate hazardous materials. There are nine primary hazard classes, each representing a distinct type of danger, often visually communicated through specific placards and labels.
How Matches Are Classified
Matches are categorized under Class 4, Division 4.1, which designates them as Flammable Solids. This classification reflects their ability to readily ignite and sustain combustion. Different types of matches receive specific UN identification numbers for transport. Safety matches, which only ignite when struck against a specially prepared surface, are assigned UN 1944. In contrast, “strike-anywhere” matches, capable of igniting on almost any rough surface, are classified as UN 1945. This distinction highlights the difference in their ignition properties and associated risks.
Properties Influencing Classification
The classification of matches as flammable solids stems from their unique chemical composition and how they ignite. The head of a safety match contains an oxidizer like potassium chlorate, along with fuels such as sulfur and antimony trisulfide, and binding agents. The striking surface on the matchbox contains red phosphorus and powdered glass.
When a safety match is struck, friction generates heat, converting red phosphorus into highly reactive white phosphorus. This white phosphorus then ignites the potassium chlorate, which releases oxygen, and the sulfur or antimony trisulfide, creating a sustained flame. This rapid, self-sustaining combustion process, coupled with a low ignition temperature, makes matches a fire hazard, fitting the definition of a flammable solid.
Safe Handling and Transport
Understanding the hazard classification of matches directly informs safe handling and transport practices. For household storage, matches should be kept in a cool, dry place, away from heat sources, moisture, open flames, and other combustible materials. Storing them in airtight containers or their original matchboxes and out of reach of children helps prevent accidental ignition.
Commercial transport of matches is subject to strict regulations concerning packaging, labeling, and documentation. These regulations specify requirements for inner and outer packaging to prevent accidental ignition during transit. For air travel, one book of safety matches is generally permitted in carry-on luggage, but “strike-anywhere” matches are prohibited in both carry-on and checked baggage due to their higher ignition risk. These measures collectively aim to mitigate the risks associated with transporting and storing flammable solids.