DNV has issued a technical paper addressing fire safety on Ro-Ro cargo spaces. This paper identifies fire hazards related Ro-Ro spaces, details the findings from almost 30 major fires in such spaces and issues recommendations for safe operation and design of fire safety systems.
The paper can downloaded as pdf-format (see "downloads" on the right hand side) and it contains several interesting findings:
- Major fires are rather in-frequent and the fatalities on ships of SOLAS standard are all linked to accidents where passengers stays on the car deck during voyage (this is no longer accepted under SOLAS and the ISM code).
- Many of the major fires start when the vessel is in port (during loading and un-loading operations). The fire detection system is then often temporarily disconnected and the CO2 system can not be released quickly due to open ramps (internally and externally).
- Reliability of the low pressure CO2 systems for cargo spaces is in general low. There are also problems with these system under normal operations.
- Conventional deluge systems for Ro-Ro decks on ferries have a good safety record.
DNV has based on the findings in the paper developed our additional class notation F-C and are working to improve the IMO and DNV standards for both CO2 and alternative fire extinguishing systems.
Additional class notation F-C
These rules are above and beyond SOLAS and apply when the owner specifies this in the newbuilding contract. The new rules will be available as Pt. 6 Ch.4 Sec.4 and will focus on:
- Reliability for the fire fixed extinguishing systems.
- Enhanced performance for the fire detection system.
- Communication (VHF / UHF) and additional fire-fighters outfit.
The measures are considered to be inexpensive. This due to the fact that although serious Ro-Ro fires are expensive, they are rather infrequent (in contrast to engine room fires). The draft F-C rules will be published as part of our July 2006 edition of the rules. The draft is available on request.
New fire fighting systems for Ro-Ro decks
There are concerns related to reliability and performance of low pressure CO2 systems. DNV has the following actions:
We have developed new rules for high expansion foam systems and inside air foam (“HotFoam”) systems. SOLAS accept these (if equivalent) under SOLAS Ch. II-2, Reg.20.6 and the new DNV rules give specific guidance. The rules were developed in cooperation with 2 makers and 3 ship-owners and were made available in January 2004 edition of the rules.
DNV takes Also part in a project to develop a new test standard for water mist protection of Ro-Ro spaces. Two test laboratories and so far one maker are involved in this work. The group has developed a preliminary test programme, this will be presented at IMO FP50 in January 2006.