WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 1
SUBSIDIARY LEGISLATION 49.02
WIRELESS INSTALLATION ON SHIPS RULES 
7th October, 1927
GOVERNMENT NOTICE 404 of 1927 , as amended by Government Notices
57 of 1929 and 330 of 1931.
Title. 
Rules.
Interpretation.
( a ) the number of hours occupied in a voyage from port to
port means the normal number of hours occupied in a
voyage between one port of call and the next;
( b ) the expression "alarm-signal" means a signal
consisting of a series of twelve dashes sent in one
minute, the duration of each dash being four seconds,
and the duration of the space separating each dash
from the following dash being one second;
( c ) the expression "operator" means one who holds the
first or second class certificate of proficiency in
radiotelegraphy from the Minister responsible for
wireless telegraphy or a certificate issued by the
Government is accepted by the Minister responsible
for wireless telegraphy as equivalent to a certificate
granted by him;
the expression "operator" in the case of a foreign ship
means one who holds a certificate of the appropriate
class issued by any government in pursuance of the
regulations annexed to the International Radio-
telegraph Convention for the time being in force;
( d ) the expression "watcher" means one who holds the
certificate as a watcher in Radiotelegraphy from the
Minister responsible for wireless telegraphy or a
certificate issued by the Government which is accepted
by the Minister responsible for wireless telegraphy as
equivalent to a certificate granted by him;
( e ) the expression "auto-alarm" means an automatic
apparatus approved by the inspector capable of
registering the alarm signal;
( f ) the expression "inspector" means the Inspector of
Wireless Telegraph appointed by the Prime Minister;
(g) the expression "installation" shall be deemed to
include an outfit of tools which shall be kept and used
in the Wireless Telegraphy Office only and also such
spare parts as are in the opinion of the inspector
necessary for the efficient working of the apparatus. 
Classification of 
ships.
3. For the purposes of these Rules, ships shall be classified as
follows: 
2 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
Class I - Ships carrying 200 persons or more;
Class II - Ships carrying 50 but less than 200 persons;
Class III -  Ships carrying less than 50 persons.
In reckoning the number of persons carried by a ship there
shall be included the normal crew of the ship and the maximum
number of passengers permitted to be carried by the passenger
certificate of the ship.
Nature of 
installation.
4. The wireless telegraphy installation with which a ship shall
be provided (hereinafter referred to as "the installation") shall be of
a type approved by the Inspector of Wireless Telegraphy to the
Government and shall in particular comply with the following
conditions:
(i) The installation shall be of the spark or
interrupted continuous wave type and shall be
capable of transmission and reception on the 600
metre wave.
(ii) The installation shall include a normal
installation and an emergency installation,
except that where the normal installation
complies with the requirements of this Rule as to
emergency installations as well as those as to
normal installations, a normal installation alone
shall suffice.
(iii) A normal installation must be capable of
transmitting clearly perceptible signals from
ship to ship over a range of at least 100 nautical
miles by day, under normal conditions and
circumstances.
(iv) An emergency installation must include an
independent source of energy capable of being
put into operation rapidly, and of working for at
least six continuous hours with a minimum range
from ship to ship of 80 nautical miles for ships
of Class I,   and 50 nautical miles for ships of
Classes II and III, and such independent source
of energy must be capable of being worked for at
least six continuous hours independently of the
source of the propelling power for the ship, the
steam supply system and the main electricity
supply system.
(v) For the purposes of this Rule an installation shall
be deemed to comply with the above
requirements as to range, if it is able to maintain
communication on a 600-metre wave, at a range
of one and a half times the number of nautical
miles hereinbefore respectively prescribed over
sea by day, with any shore wireless telegraphy
station licensed by the competent authority of
the place where it exists, when employing a
receiver without amplification devices.
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 3
Alternatively the installation must operate
with sufficient power to give under normal
working conditions 60 metre amperes in the case
of a main installation, 45 metre amperes in the
case of an emergency installation on a 1st Class
ship and 26 metre amperes in the case of an
emergency installation on a 2nd Class ship. The
number of metre amperes is obtained by
multiplying the maximum current (R.M.S.)
intensity in amperes in the aerial by the
maximum height in metres of the highest point
of the aerial above the deepest load water line.
Electrical power.
installation efficiently in addition to that necessary for other
purposes.
Installation.
compartment (hereinafter called the wireless telegraph room)
which must be placed in a position well above the water line and
such that extraneous noises do not interfere with reception.
All dangerous parts of the installation must be either
screened or effectively isolated.
Means of 
communication.
7. There shall be provided, between the bridge of the ship and
the wireless telegraph room, means of communication by voice
pipe, telephone or other means.
Clock.
wireless telegraph room.
Books, papers and 
publications. 
Amended by:
G.N. 330 of 1931.
9. The following books, papers and publications are to be
readily accessible in the Wireless Telegraph room -
( a ) a copy of these Rules;
( b ) the current edition of the "Handbook for Wireless
Telegraph Operators working Installations licensed by
the Minister responsible for wireless telegraphy";
( c ) the ship’s wireless telegraph licence;
( d ) the international list of telegraph offices;
( e ) the International List of Radiotelegraph Stations, with
latest supplements;
( f ) Liste Alphabetique des Indicatifs d’Appel , with latest
supplements;
( g ) the latest issue of the Post Office Guide;
( h ) handbook of instructions for the working of the
wireless telegraph set;
( i ) an adequate supply of wireless telegraph forms;
( j ) a wireless telegraph log to contain a chronological
record of all messages sent and received, and of all
calls heard, or transmitted.
4 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
Ships not fitted 
with approved 
automatic 
apparatus.
10. If not fitted with an approved automatic apparatus for
registering the alarm signal:
(i) a ship of Class I shall carry operators in accordance
with the following table, and while at sea, an operator
shall always be on watch:
(ii) A ship of Class II shall carry operators and watchers in
accordance with the following table, and while at sea
an operator shall always be on watch at the time
specified in Schedule I to these Rules, and either an
operator or a watcher shall always be on watch at other
times. Where only one operator is required to be
carried, either he shall be on watch throughout the
voyage or the ship shall be provided with automatic
apparatus approved by the Inspector of Wireless
Telegraphy to the Government. In the last mentioned
case the operator shall keep watch at such periods as
are prescribed in Rule 13. At all other periods watch
shall be kept by means of an auto-alarm.
Auto-alarm in the 
case of Class II 
ships.
11. Within a period of twelve months from the date on which
an auto-alarm is approved by the Department of Trade and the
Minister responsible for wireless telegraphy, a ship of Class II shall
be fitted with such apparatus unless   the duration of the voyage on
which it is   employed does not exceed eight hours from port to port,
provided that this rule shall not apply to a ship of Class II so long
as it complies with rule 10 for a ship of Class I.
Ship fiited with 
auto-alarm.
12. If fitted with an auto-alarm approved as aforesaid:
(i) a ship of Class I shall carry operators in accordance
with the following table and while at sea an operator
Nature of voyage No. and Grades of Operators
( a ) Voyage exceeding 48
hours from port to port
3 operators, of whom one shall
be an operator of the 1st grade
and not more than one an
operator of the 3rd grade.
( b ) Voyage exceeding 8
hours but not exceeding 48
hours from port to port
2 operators of whom one shall
be of the 1st or 2nd grade.
( c ) Voyage not exceeding 8
hours from port to port
1 operator who shall be of the
1st or 2nd grade.
Nature of voyage No. and Grade of Operators and 
Watchers
( a ) Voyage exceeding 48
hours from port to port
1 operator who shall be of the
1st grade or 2nd grade, and 2
watchers
( b ) Voyage exceeding 8
hours but not exceeding 48
hours from port to port
1 operator who shall be of the
1st or 2nd grade, and 1 watcher.
( c ) Voyage not exceeding 8
hours from port to port
1 operator who shall be of the
1st or 2nd grade.
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 5
shall always be on watch during the times specified in
Schedule I to these Rules, and a watch shall be
maintained at all times either by an operator or by
means of the auto-alarm.
(ii) a ship of Class II shall carry one operator who shall be
of the first or second grade, and while at sea the
operator shall be on watch during the times specified
in Schedule I to these Rules, and a watch shall be
maintained at all other times by means of the auto-
alarm.
(iii) a ship of Class III shall carry one operator who shall
be of the first and second grade and, pending the
making of further rules, altering the times of watch to
be observed on such ships, the operator shall, while the
ship is at sea, always be on watch at the times
specified in Schedule I to these Rules.
Vessels engaged in 
passenger traffic.
13. (1) Vessels belonging to Class II employed on the
passenger service between Syracuse and Malta shall conform to the
following rules:
( a ) if only one operator is carried, he shall be on watch on
the outward voyage from Malta for one hour after
leaving Malta until reaching Cape Passero. On the
homeward voyage to Malta he shall be on watch from
Cape Passero until within one hour’s steaming of
Malta. At all other times, watch shall be maintained by
means of the auto-alarm;
( b ) in order to ensure that the wireless telegraph apparatus
is in working order, communications shall be
established with St. George’s Radio, on each round
voyage, at a distance of not less than fifty miles.
(2) Vessels belonging to Class II, employed on the passenger
service between Tunis and Malta shall conform to the following
rules:
( a ) such vessels shall carry one operator. They must in
addition either carry one watcher or be provided with
an auto-alarm.
( b ) while the ship is at sea, an operator or watcher shall be
on watch during the periods specified in Schedule I to
these Rules. If no watcher is carried, watch shall be
kept by means of the auto-alarm at the times the
operator is not on watch;
( c ) in order to ensure that the wireless telegraph apparatus
is in working order, communication shall be
established with St. George’s Radio, at a distance of
Nature of voyage No. and Grade of Operators 
( a ) Voyage exceeding 48
hours from port to port
2 operators, one of whom shall
be of the 1st grade
( b ) Voyage exceeding 48
hours from port to port
1 operator who shall be of the
1st or 2nd grade.
6 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
not less than 50 miles, on each round voyage.
Approval of auto-
alarm.
14. An auto-alarm shall not be approved unless it complies
with the conditions specified in Schedule II.
Ships fitted with 
auto-alarm.
15. In ships fitted with an auto-alarm:
(i) A means of giving audible warning shall be provided
in the wireless telegraph room, in the wireless
operator’s cabin, and on the bridge. This warning shall
operate continuously after the alarm has been actuated
by the alarm signal, until stopped as indicated below.
The audible warning shall also operate as above if a
disconnection occurs in the circuits of the filaments of
the valves.
(ii) Only one switch for stopping the operating of the
audible warning shall be provided and this must be
situated in the wireless telegraph room.
(iii) A change-over switch or system of switches
mechanically coupled together shall be provided for
changing over from normal reception to reception by
the auto-alarm. The aerial shall be associated with the
switch or switches in such a manner that the necessary
connections to enable the alarm to respond to the tests
laid down in rule 18 cannot be made unless the aerial
is connected to the auto-alarm.
(iv)  The auto-alarm must be susceptible to local excitation
by the testing buzzer, so that the working of the
installation as a whole can be tested. A key may be
provided so that when desired the bridge bell can be
prevented from ringing when the alarm is being tested
but the key must be so designed that unless held down
it automatically establishes the circuit of the bridge
bell.
Qualifications of 
operators.
Amended by:
G.N. 57 of 1929;
G.N. 330 of 1931.
16. For the purposes of these Rules operators shall be graded
into three grades as follows:
( a ) A "First Grade Operator" is one who holds the First
Class Certificate of Proficiency from the Minister
responsible for wireless telegraphy issued under the
provisions of the International Radiotelegraph
Convention (London), 1912, or the First or Second
Class Certificate of Proficiency issued bt the Minister
responsible for wireless telegraphy under the
provisions of the International Radiotelegraph
Convention (Washington), 1927, and who has had
three years’ experience as an operator at sea, of which
period two years shall have bean in a ship where fixed
hours of watch are kept.
( b ) A "Second Grade Operator" is one who holds the First
or Second Class Certificate of Proficiency issued by
the Minister responsible for wireless telegraphyand
can produce evidence that he has had six months’
satisfactory experience as an operator at sea.
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 7
( c ) A "Third Grade Operator" is one who holds the First or
Second Class issued by the Minister responsible for
wireless telegraphy, or Special Certificate of
Proficiency, and who has not had less than six months’
experience as an operator at sea.
( d ) An "operator" is one who holds a local certificate of
proficiency granted by the inspector.
( e )  The Prime Minister may grant certificates to operators
and watchers and may accept certificates granted to
operators by the Government in pursuance of the
regulations annexed to any international
radiotelegraph Convention for the time being in force.
An operator of the second or lower grade who has not
during the last two years been employed at sea as an operator in a
ship having fixed hours of watch may be required by re-
examination or otherwise as necessary to show that he still
possesses the qualifications described on his certificate.
The ship’s wireless 
telegraph service.
Cap. 49.
17. ( a )  The master shall take steps to ensure that the wireless
telegraph service of the ship is maintained in
accordance with these Rules and with the conditions of
the licence granted by the Minister responsible for
wireless telegraphy under the Wireless Telegraphy
Ordinance.
( b ) The master shall require that an operator or watcher is
on duty at the proper time and that he does not leave
the wireless telegraph room unless another operator or
watcher takes his place.
( c ) Sufficient power for the operation of the ship’s main
wireless installation shall be available when required
for the transmission of signals at all times whilst the
ship is under way.
( d ) In ships where the dynamo supplying the main
installation is not run continuously at sea there shall he
efficient means of communication to enable the
wireless operator to apply for power without leaving
the wireless telegraph room.
( e ) The emergency installation shall be used only for the
purpose for which it is installed except when it is
desirable that communication should be limited to very
short ranges.
( f ) Batteries, whether forming part of the main or
emergency installations, shall be maintained in a fully-
charged condition, and power must be available for
charging the batteries at a definite time each day.
( g ) A record of the batteries shall be kept on forms similar
to those scheduled to these Rules. These records shall
be open to inspection by the inspector.
Ships fitted with 
auto-alarms.
18. In the case of ships fitted with auto-alarms:
8 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
(i) In ships in which watch is kept at certain specified
hours but is not continuous, the master shall require
the operator, when going off watch, to test the auto-
alarm and report to him or to the officer on the bridge,
whether it is in working order, and to keep a record of
the tests.
(ii) In ships in which watch is not kept at specified hours,
the master shall require the operator to test the auto-
alarm at frequent intervals, with not more than twelve
hours between any two tests, and report to him or to
the officer on the bridge whether it is in proper
working order, and to keep a record of the tests.
(iii) If a key for disconnecting the bridge bell, as permitted
in paragraph (iv) of rule 15 has been fitted, the master
shall require the bridge bell circuit to be tested at least
once even twenty-four hours, and an appropriate entry
made in the record of tests of the auto-alarm.
(iv) In the event of the failure of the auto-alarm on a ship
having no fixed working hours, the master shall
require the operator to keep the hours at watch
specified in Schedule I until the defects have been
remedied.
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 9
SCHEDULE I
Time of watch for ships required to carry one or two operators
Zones Western limit Eastern limit Times of watch 
for one operator 
Greenwich 
Mean Time
Times of watch 
for two 
operators 
Greenwich 
Mean Time
A.Eastern 
Atlantic, 
Mediterranean, 
North Sea, 
Baltic, Western 
Arctic Sea.
Meridian of
30ºW coast of
Greenland
Meridian of
30ºE, to the south
of the cost of
Africa, eastern
limit of
Mediterranean,
Black Sea, and of
the Baltic, 30ºE
to the north coast
of Norway
8h. to 10h. 
12h. to 14h.
16h. to 18h.
20h. to 22h.
0h. to 5h.
8h. to 14h.
16h. to 18h.
20h. to 22h.
B. Indian Ocean, 
Eastern Arctic 
Sea
Eastern limit of
Zone A
Meridian of 80 E,
west coast of
Ceylon to
Adam’s Bridge,
then westward
round coast of
India
4h. to 6h.
8h. to 10h.
12h. to 14h.
16h. to 18h.
0h. to 2h.
4h. to 10h.
12h. to 14h.
16h. to 18h.
20h. to 24h.
C. China Sea, 
Western Pacific 
Ocean
Eastern limit of
Zone B
Meridian 160ºE 0h. to 2h.
4h. to 6h.
8h. to 10h.
12h. to 14h.
0h. to 2h.
8h. to 10h.
12h. to 14h.
16h. to 22h.
D. Central 
Pacific Ocean
Eastern Limit of
Zone C
Meridian 140ºW 0h. to 2h.
4h. to 6h.
8h. to 10h.
20h. to 22h.
0h. to 2h.
4h. to 6h.
8h. to 10h.
12h. to 18h.
20h. to 24h.
E. Eastern 
Pacific Ocean 
Eastern Limit of
Zone D
Meridian of
70ºW, south of
the coast of
America, west
coast of America
0h. to 2h.
4h. to 6h.
16h. to 18h.
20h. to 22h.
0h. to 2h.
4h. to 6h.
8h. to 14h.
16h. to 22h.
F. Western 
Atlantic Ocean 
and Gulf of 
Mexico
Meridian 70ºW
south of the coast
of America, east
coast of America
Meridian of
30ºW, coast of
Greenland
0h. to 2h.
12h. to 14h.
16h. to 18h.
20h. to 22h.
0h. to 2h.
4h. to 10h.
12h. to 18h.
20h. to 22h.
10 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
SCHEDULE II
1. The function of the auto-alarm is to give warning of the receipt of a distress
call on 600 meters when watch is not being kept by an operator.
2. An auto-alarm must comprise -
( a ) a wireless receiver, capable of receiving waves of 600 metres, spark or
i.c.w.;
( b ) a selector that is to say a means of selecting one definite signal known
as the alarm;
( c ) an alarm, that is to say, a means of giving audible warning such as a bell
or hooter.
The apparatus necessary under paragraph ( a ) must be an integral part of the auto-
alarm, and when installed may only be used as such.
3. An auto-alarm must fulfil the following conditions:
( a ) The wireless receiver must respond without re-adjustment to signals on
wave lengths between 585 and 615 metres from a transmitter of the
spark type, having a steady note frequency of not less than 100 per
second, when the strength of signals is such that the field strength is
equivalent to that which would be produced by a transmitter making use
of 45 metre-amperes as defined in paragraph (v) of rule 4 at a distance
of 80 miles.
( b ) (i) The selector must be operated only by energy received by the
wireless receiver and must respond to all signals as described in
paragraph ( a ) above for the wireless receiver.
(ii) The selector must be of such design as to operate the alarm during
the reception of the alarm signal at the termination of three consecutive
dashes.
( c ) The alarm must be operated only by energy received from the selector
and be of approved type.
4. Before approval as a standard type for installation in ships an auto-alarm
must comply with the following tests -
(i) The selector must in conjunction with the wireless receiver respond to
100 consecutive test-calls, produced locally; each call to consist of three
consecutive dashes under conditions free from interference.
For the purposes of this test the timing of the beginning and the ending
of each of the test dashes shall not differ by more than 1 second from
the correct timing of the alarm signal of 12 dashes (Rule 2), always
provided that the dashes are not to be of less than 3½ nor more than 4½
seconds’ duration ,  and the spaces of not less than one fifth nor more
than 1½ seconds’ duration.
(ii) The auto-alarm shall be installed for 14 days in an area where
interference conditions are severe on the 600 metres wavelength and the
selector, in conjunction with the wireless receiver, must not respond in
such a manner as to operate the alarm more than twice a week to signals
other than the alarm signal or the test signals indicated in (i) above.
During this period tests of the sensitivity of the receiver shall be made
in accordance with paragraph ( a ) of rule 3.
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 11
(ii) A farther test of 28 days’ duration shall be imposed with the object of
ascertaining the reliability of the auto-alarm under interference
conditions. For this purpose the auto-alarm shall be joined normally to
an external aerial, and the energy necessary for operating the auto-alarm
shall be produced locally by a buzzer or other suitable appliance
coupled to the aerial system; the energy given to the aerial by this
means shall be of not less amount than that furnished for the tests
indicated under paragraph ( a ) of rule 3. Each test call shall consist of
the alarm signal. During this period of 28 days a minimum of 500 such
test calls shall be made ,  of which 90 per cent must actuate the alarm and
the alarm must not be actuated more than twice a week by other signals.
Adjustments of the apparatus shall not be made more often than once
every 12 hours.
(iv) During every third day of the test laid down in sub-paragraph (iii)
above, the selector and the wireless receiver will be subjected to
varying temperature conditions; for this purpose the selector and
wireless receiver will be enclosed in a chamber the interior of which
will be raised in one hour to a temperature of 45º C   (113ºFah.),
maintained at that temperature for two hours and then allowed to cool
naturally.
12 g S.L.49.02 WIRELESS INSTALLATION ON SHIPS 
SCHEDULE III
Ship battery log
Daily record
Name of Ship .........................................
Type of Battery .............................. Date supplied ......................
Monthly examination
Volts of whole battery on open circuit .........................................
Volts of whole battery on minimum artificial discharge ...............
Volts of whole battery on maximum artificial discharge ..............
Volts of whole battery when working emergency gear .................
Date
V
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S.G. of each Cell as measured Temp. of Acid Corrected S.G
1 Before 
charge
After charge Before 
charge 
After charge Before 
charge 
After charge
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
WIRELESS INSTALLATION ON SHIPS  g S.L.49.02 13
Note: This table is not required in the case of alkaline electrolyte cells.
Volts of whole battery on open circuit after discharge ........................
