Single Jacket and Double Jacket Fire Hose—What’s the Difference? A guide for beginners.
Besides the number of polyester jackets, what is the difference between these two fire hoses? Knowing the distinction is essential to determining what is best for your project and application.
If you are new to buying hoses, it may surprise you to learn that although there are attributes that set these hoses apart, their construction is quite similar. The best place to start is with the basics!
What are single and double jacket hoses made of?
Both single and double jacket hoses are made up of two components: the inner lining and the outer jacket(s). The lining in a modern fire hose is a single ply of EPDM rubber. The characteristics of EPDM rubber are its durability and resistance to chemicals. The rubber lining itself, although designed with a tensile strength of 1800 PSI, will not hold fluid pressure. Without a jacket, the tube itself would essentially blow up like a balloon and burst!
The woven jacket consists of ring spun polyester yarns that are engineered to resist abrasion, mold, and mildew. The jackets are woven on large circular looms specific to the size of the fire hose they will ultimately become. The jacket gives the hose its strength and pressure rating. While the majority of jacketed hose is white, there are a variety of colors available. To achieve coloration, the jacket is impregnated with a dye, also known as hypalon coating.
How are they constructed?
The linings are inserted and pulled through the jackets and subjected to a steam vulcanizing process that bond the jacket to the lining. Single jacket fire hose is burst tested to 900 PSI. In order to meet NFPA requirements, single jacket hose must be service tested annually to 300 PSI.
Double jacket hose has an extra layer of woven fabric that boasts a higher wear ability in comparison to the single jacket hose. It has an impressive burst test of 1,200 PSI and a 400 PSI service test. Although the double jacket hose is more costly than the single jacket, it posses a service life that is double that of its single jacket counterpart, living up to its name in more than one way!
Did you know that there are many types of single jacket hoses as well as double jacket?
Rack and Reel fire hose is technically a single jacket hose and is manufactured to meet a specific application. Hospitals, airports, hotels, and other municipal or public buildings typically have these hoses prefolded in a pin rack or cabinet for fire emergencies.
MSHA (Mine Safety and Health Administration) approved hose is also another type of single jacketed hose. MSHA hose meets certain specifications and has the ability to self-extinguish when a flame source is removed. The lining of a MSHA hose is made of synthetic rubber, which does not produce toxic gases when ignited.
Last but not least is the mill discharge, or sometimes dubbed, contractor hose. Mill hose comes both single jacketed and double jacketed. Mill discharge hoses, though similarly constructed to regular single and double jacket hoses, have a slightly lower pressure rating. Often times, construction sites, parks, or agriculturists will employ these hoses for undemanding purposes such as watering crops, draining a pond, or simply transferring water from A to B. It is important to note that for washdown purposes, a rubber-covered hose is the way to go.
When it comes down to it, choosing the correct hose for your application is crucial, both for your safety and for your project’s timely completion. Contact your team at Rawhide to help you find the right hose today.