What does the term 'specific density' refer to?

The term 'specific density' commonly refers to the ratio of the density of a substance to the density of a reference substance, typically water for liquids and solids. This concept helps in determining how heavy a substance is relative to water, which has a density of approximately 1 g/cm³ at standard conditions.

In the context of liquids, the specific density provides insight into whether the liquid will float or sink in water. If the specific density is less than 1, the liquid will float; if it's greater than 1, it will sink. This property is crucial in various fire protection scenarios, such as understanding how different firefighting foams or agents behave when deployed in water or when they come into contact with flammable liquids.

Understanding specific density in relation to water is pivotal for fire protection professionals, as it aids in selecting appropriate firefighting techniques and agents necessary for effectively combating fires involving various types of liquids.