7 Characteristics

The emergency alarms, alarms and call signals listed should have the audible and visual characteristics shown in the tables of this section. All other alerts, indicators and call signals should be clearly distinct from those listed in this section to the satisfaction of the Administration. These tables are not all-inclusive and other alerts may be added by the Administration in a manner consistent with this Code.

Table 7.1.1 Emergency alarms

(Note: See table 7.2 for audible signals)
Function	IMO Instrument	Audible		Visual		Remarks
		Device	Code	Colour	Symbol*
General emergency alarm	LSA 7.2.1 SOLAS III/6.4 SOLAS II-2/7.9.4	Whistle Siren Bell Klaxon Horn	1.a, 1.b	Green/White		Used for summoning passengers to the assembly stations.
						Used for summoning the crew to the boat stations.
						Sound levels in accordance with LSA Code 7.2.1.2, 7.2.1.3
Fire alarm	SOLAS II-2/7.9.4	Bell Klaxon Siren Horn	2, 1.b	Red		Used for summoning the crew to the fire stations on passenger ships.
	FSS 9.2.5.1	Bell Klaxon Siren Horn	2, 3.c, 3.d	Red		Horn/bell in machinery space, buzzer/bell elsewhere.
Fire-extinguishing pre-discharge alarm	FSS 5.2.1.3	Siren Horn	2	Red		Signal precedes release
						Audible signal distinct from all others. When other fire-extinguishing mediums are used they should be clearly identifiable.
Power-operated sliding watertight door closing alarm	SOLAS II-1/13.7.1.6 and 13.8.2	Horn Klaxon bell	2	Red Green	No symbol allocated	Signal at door precedes and continues during door closing. At remote position; door open – red indicator, door closed – green indicator. Red indicator on navigation bridge flashes while door closes.
Water ingress detection main alarm	SOLAS XII/12.1, 12.2and II-1/23-3	Bell Buzzer Horn	2	Red		For cargo holds used for water ballast and the ballast tanks, an alarm overriding device may be installed.
* For use with visual indicator columns (see Appendix).

Table 7.1.2 Alarms

(Note: See table 7.2 for audible signals. For the presentation of navigation related alerts, resolution MSC.191(79) should be observed.)
Function		IMO Instrument	Audible	Visual*		Remarks
Function		IMO Instrument	Device	Code	Colour	Remarks	Symbol*
Machinery alarm		SOLAS II-1/51.1	Horn Buzzer	3	Amber		Horn in machinery space, buzzer elsewhere.
Steering gear alarm		SOLAS II-1/29.5.2 II-1/29.8.4 II-1/29.12.2 II-1/30.3	Horn Buzzer	3	Amber		Horn in machinery space, buzzer elsewhere.
Control system fault alarm		SOLAS II-1/29.8.4 II-1/49.5	Horn Buzzer	3	Amber	No symbol allocated	Horn in machinery space, buzzer elsewhere.
Bilge alarm		SOLAS II-1/48	Horn Buzzer	3	Amber		Horn in machinery space, buzzer elsewhere.
Engineers' alarm		SOLAS II-1/38	Horn Buzzer	3	Amber		Horn/buzzer in engineers‘ corridors, buzzer in engineers‘ cabins.
Personnel alarm		Resolution A.481(XII), annex 2, paragraph 7.3	Horn Buzzer	3	Amber		Horn in machinery space, buzzer elsewhere.
Fire detection alarm		FSS 8.2.5.2	Bell Buzzer Horn	2	Red
		SOLAS II-2/7.4.2 FSS 9.2.5.1	Ditto	2	Red		Should automatically actuate fire alarm if not acknowledged in 2 minutes or less. Horn/bell in machinery space, buzzer/bell elsewhere.
		FSS 10.2.4.1.3	Ditto	2	Red
Activation of fixed local Application Fire-extinguishing system		SOLAS II-2/10.5.6.4	Ditto	2	Red
Water ingress detection pre-alarm		SOLAS XII/12.1, 12.2 and II-1/23-3	Bell Buzzer Horn	2	Amber		For cargo holds used for water ballast, an alarm overriding device may be installed.
Alarm system fault alarm		SOLAS II-1/51.2.2	Horn Buzzer	3	Amber	No symbol allocated	Horn in machinery space, buzzer elsewhere.
Flashing light/ Rotating light		6.1 of the present Code	—	—	White	No symbol allocated
Cargo alarm		IBC, BCH, IGC, GC	Horn Buzzer	3	Amber	No symbol allocated	See tables 9.1.1 to 9.1.8 for IMO instrument references. Horn in machinery space, buzzer in engine control room, cargo control station and navigation bridge.
Gas detection alarm	For chlorine gas	IGC 17.14.4.3 17.14.1.4 GC 17.12.5(d)(iii) 17.12.5(a)(iv)	Siren Horn Bell	2	Red
Gas detection alarm	Except for chlorine gas	IGC 13.6, 17.9, 16.2.1.2 , 16.2.9GC 13.6, 17.11, 16.2(b), 16.10	Buzzer Horn	3	Amber		xxx Gas abbreviation may be indicated.
Power-operated sliding watertight door fault alarm		SOLAS II-1/13.7.3 II-1/13.7.8	Horn Buzzer	3	Amber	No symbol allocated	Horn in machinery space, buzzer elsewhere.
* For use with visual indicator columns (see Appendix).

Table 7.1.3 Call Signal

(Note: See table 7.2 for audible signals.)
Function	IMO Instrument	Audible		Visual*		Remarks
Function	IMO Instrument	Device	Code	Colour	Symbol*	Remarks
Telephone	SOLAS II-1/50	Horn Buzzer Bell	3.a	White		Horn/bell in machinery spaces and engineers‘ accommodation corridors; buzzer/bell in engine control room, on navigation bridge and in engineers‘ cabins.
Engine-room telegraph	SOLAS II-1/37	Horn Bell Buzzer	2, 3.a	White		Horn/bell in machinery space, buzzer/bell in engine control room and on navigation bridge.
* For use with visual indicator columns (see Appendix).

Table 7.2 Audible signals and call waveforms

Audible Code	Waveform	Remarks
1.a		General emergency alarm.
1.b	Specific codes per muster list	General emergency alarm.
2		Continuous until silenced or acknowledged.
3.a		Optional waveforms to provide distinction between alarms. Pulse frequency between 0.5 Hz and 2.0 Hz.
3.b
3.c
3.d