Features Training
Back to Basics: May 2010

In February I attended a factory tour of Snap-Tite Hose Inc. in Erie, Pa. The tour involved two plants that produce rubber-jacketed and cotton-jacketed fire hose. The fire hose is the main tool used in engine company operations, for both attack and supply lines, as one of the major jobs of the engine company is to deliver water both on the fire and to the apparatus.

Photo 1: Sections of hose that have been tested to fail at extreme pressures. Photos by Mark van der Feyst

Photo 2: All Snap-Tite hoses feature a label that includes a bar code and 10-digit identification number. Photos by Mark van der Feyst

As we all know, fire service hose comes in various sizes and lengths and is designed for specific purposes. Attack lines range from 1.5 inches to 2.5 inches; supply lines range from three inches to six inches.

Over the years, fire service hose has changed and improved. We now see greater flows of water with less friction loss due to technological advances in materials such as the inside liner of the hose. The more laminar the liner, the less friction loss there is.

Rubber-jacketed and cotton-jacketed hose have a cotton weave inside. This cotton weave starts as a thin piece of string on a spool and is fed into a round weaving machine. The multiple strands of string all come together and form into a round shape that becomes a continuous length of hose. Rubber-jacketed hose has a cotton weave that is imbedded into a rubber liner and rubber jacket. Sections of rubber hose are constructed in lengths of 700 feet, allowing the hose to have no seams in the cotton weave, the rubber jacket or the liner. Once the rubber coating has been applied, it is steamed to allow the rubber to vulcanize, or cure, properly. This process allows the two materials to become one, giving the hose a very high strength ratio. The same process is conduced for cotton-jacketed hose except for the fact that a second cotton jacket is applied to the outside and is then vulcanized.

Once the hose is constructed it is cut into 100-foot sections and couplings are added. The hose is then service tested to ensure it is acceptable for use. The inside of the hose is where we want to be sure we have the best material; material that is smooth and laminar will allow water to flow much more efficiently, with less frication fighting against it. Some of the inside material is designed to prevent kinking at pressures as low as 50 psi. (For competitive reasons, Snap-Tite did not want to share its material secrets.)

Fire hoses can fail due to many factors. Photos by Mark van der Feyst

When fire service hose fails – which can happen, due to many potential factors – the hose is designed to burst a certain way to limit injury. Fire service hose can withstand and is tested to extreme pressures, ensuring that it will not fail during average use. However, when fire service hose does fail, it is designed to do so in a way that limits any injury or further damage. In photo 1, you can see two examples of proper or good hose bursts. Both sections of test hose have parallel breaks. These two test sections were used in a quality control test to measure the strength of the hose. These hose sections were randomly chosen. The red hose was tested in front of us on the day of our visit. That section of hose failed at a pressure of 920 psi, well above the required working pressure and service test pressure that NFPA dictates. This quality control test is designed to make the hose section fail to see how it behaves. In regular pressure tests conducted on all hose manufactured by Snap-Tite the hoses are charged only to between 400 psi and 600 psi.

Another feature that was shown on our tour is the hose identification tag system (see photo 2). Each section of hose is supplied with an identification label that is placed on the female coupling. The label sits next to the lug, allowing it to be protected somewhat from normal wear and tear. The label includes a bar code and a 10-digit identification number. The label is unique to that section of hose. It is implemented at the birth of the hose section, allowing Snap-Tite to monitor the testing of each section along with the remaining production process. This identification label system is transferable to the fire department that purchases the hose. If the fire department chooses to subscribe to Snap-Tite’s hose record management service, it can use the system to track its hose service life. All pertinent information is tracked and recorded for the department to use and view. Dates when the hose section was last service tested, when it was put into service, when it was taken out of service, any damage that was incurred during service life and any repairs that were made are all recorded and kept in this data management system. This saves fire departments from having to label each section of hose with their own identification numbers and starting a record of that hose. 

Unfortunately, I was unable to take photos inside the facility as it was not permitted. However, having seen how fire service hose is constructed, manufactured and tested has made me realize that this basic tool that we use every day is certainly designed to withstand the harshest of work environments.              

Mark van der Feyst is a 10-year veteran of the fire service. He works for the City of Woodstock Fire Department and is an instructor teaching in Canada and the U.S. Mark is a local level suppression instructor for the Pennsylvania State Fire Academy, an instructor for the Justice Institute of BC and an associate professor of fire science for Lambton College. He can be contacted at Mark@FireStarTraining.com