: How do you define something as flammable? Which criteria of an object is used as reference?

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: How do you define something as flammable? Which criteria of an object is used as reference?

In: Physics

2 Answers

Anonymous 0 Comments

There are multiple definitions. Sometimes it makes a lot of sense to even categorize them based on their flamability. In general something is considered flammable if it releases energy when you expose it to hot air. For example NFPA 704 scores materials as a 0 on flamability if it does not catch fire in air when exposed to 820 °C for five minutes. However other classifications and standards have different thresholds.

Anonymous 0 Comments

An objects (usually a liquids though) Flashpoint is used. Which is the minimum temperature necessary to cause an item to catch fire.

For liquid this is ~100°F.

For solids its any solid that is readily combustible or can cause combustion through friction. Lithium for batteries comes to mind, which will readily combust/react when exposed to the air.

Edit: I’ve used transportation standards as a reference, different samtandards classify flammability differently depending on the nature of the work being done. 100°F would make for a class 3 flammable liquid i believe.