(IV-7-3) General Safety

Rules IV Industrial Services
Part 7 Offshore Technology
Chapter 3 General Safety
Section 9
Fire and Gas Detection Alarm Systems
Section 9
Fire and Gas Detection Alarm Systems
A General ....................................................................................................................... 9-1
B Manual Alarm.............................................................................................................. 9-2
C Arrangement of Fire Detectors and Alarm Loops ....................................................... 9-2
D Public Address and General Alarm System................................................................ 9-3
A
General
A.1 Fire detection system
A.1.1 Every offshore installation/unit shall be provided with an automatic fire detection and alarm
system for all accommodation and service spaces.
The following types of fire detectors / detection units may be used in different locations on the substation:
• ionization/smoke detectors for all enclosed operating areas, store rooms sleeping quarters, stairways,
passageways and escapes within accommodation areas
• heat detectors, preferably in galleys and day rooms
• differential and flame detectors for operating areas subject to high air speeds and for areas on the
open deck
• Aspirating smoke detection systems with assigned detection units and sampling pipes in those areas,
where other detector types are not recommended, e.g. for reasons of easy test and maintenance,
i.e. in high rooms such as High Voltage Switchgear rooms.
A.1.2
For details concerning arrangement and layout of fire detectors refer to C further below.
A.1.3 Eventually, a dedicated Closed Circuit TV system (CCTV) should be installed additionally for
remote surveillance.
A.2 Gas detection system
A.2.1 A fixed automatic gas detection and alarm system may be required depending on the detailed
design of an Offshore Wind Farm Substation. Such gas detection system is to be so arranged as to monitor
continuously all areas where an accumulation of flammable gas or explosive gas mixture could occur.
An accumulation of hazardous gas on an Offshore Wind Farm Substation may e.g. be possible in the
following locations, as applicable:
• in battery rooms (H2 generation due to faulty batteries or chargers)
• in locations with Hypochlorite Generation Plants (if H2 leakage is possible due to the design)
• in paint stores
• in fuel tanks or at fuel tank openings, depending on the flashpoint of the respective fuel stored
• at Helicopter refueling units
• in ventilation outlets from above hazardous area spaces
Depending on their location, it may be also required to install gas detectors in intakes for ventilation air,
e.g. in living quarters or emergency shelters.
A.2.2 Additionally, the possibility of an SF6 leakage in the MV/HV switchgear rooms should be taken
into account. Such gas is used as an insulator in gas insulated switchgear (GIS).
SF6 is normally non-toxic and odorless, however, it is known as the strongest greenhouse gas and toxic
fluoride compounds could develop from SF6 during long term operation of the GIS.
Edition 2013 Germanischer Lloyd Page 9–1