What does the term "unlined hose" describe?

The term "unlined hose" refers specifically to a hose that is constructed with only a single jacket, which allows it to swell when it becomes wet. This characteristic is particularly important in firefighting situations where the hose may be exposed to water or other liquids. The swelling can help create a tighter seal, preventing leaks and improving the overall performance of the hose during operation.

In contrast, hoses with multiple layers tend to have reinforced construction, contributing to their durability and pressure handling capabilities. Hoses designed for increased pressure have special features and reinforcements to accommodate higher stress, while hoses made of synthetic materials can provide lightweight options but do not directly connect to the definition of "unlined hose." Understanding the unique attributes of unlined hoses is vital for ensuring that firefighters utilize the right equipment for various scenarios, especially in emergencies where reliability is critical.