Incident Report

Subject:                            5" Fire Hose With Storz Fittings - Failure Awareness

Date of Email reporting Incident:   Fri 14/11/2003 14:08

Report Detail:

5" Fire Hose With Storz Fittings - Failure Awareness

This came in from one of our UK Safety Managers.  The original I believe came from the States.

Last week our site has a failure of a piece of 5" LDH while flowing water. The Storz type connector slid off the end of the hose. The hose did not exhibit any type of tear, rip, fraying and etc. The hose was hydrotested annually as required by NFPA.

The hose coupling in question was manufactured by Jaffrey.  During my research into the event, I discovered the following information in NFPA-1962 (1998 Edition) Standard for the Care, Use, and Service Testing of FIre Hose Including Couplings and Nozzles.

4-2.6 When couplings are attached or reattached to hose, the hose shall be tested at its service test pressure in accordance with Chapter 5.

4-2.8 The socket head cap screws on shank-type couplings shall be checked at least annually to ensure they are torqued to the manufacturer's specified tolerance.

The above information (4-2.8) does not appear in the instructions listed for how to test fire hose in the NFPA standard (5-5 and 5-6). This step for torquing was not being done during our annual hydro-test. We are requiring this step on all future tests. Additional information gathered from our supplier includes:

1) Jaffrey is no longer in business. These couplings had a history of detaching themselves.

2) Jaffrey had no known torque specification for these cap screws.

3) Jaffrey used a two piece shank-type coupling for attaching the end to the hose.

4) A three pice shank-type coupling is used by most manufacturers today.

5) Harrington, Inc. recommends 25-30 ft. lbs. of torque for their hose coupling attachments.

I am asking if other sites have had any large diameter hose failures and what causes were identified. Are other sites torquing their cap screws as part of their annual hydrotest? What brands of connections do you have and what torque specification are you using?

I look forward to any available information as I continue to prepare my report on our incident. I will offer the results of my research at a future time.