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CPD Seminar
A Review of Advanced Topics in Lift Engineering
Only for Internal Circulation during CPD Lectures 2
Lift and Escalator Safety and their Protection
Ir Charles Wong
Date: 21 Nov. 2016
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Introduction
• Lifts and Escalators Mechanism in
HK
• Lift System
• Escalator System
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The (Lifts & Escalators)mechanism governed by the Hong Kong
• Lift and Escalator Ordinance (i.e. Cap327, 618);
• Lifts and Escalators (General) Regulation;
• Lifts and Escalators (Fees) Regulation;
• Cap 590 Factories and Industrial Undertakings (Goods Lifts) Regulation
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The relevant COPs for lifts & Escalators Works in Hong Kong
• Code of Practice on the Design and Construction of Lifts and Escalators - EMSD;
• Code of Practice for Lift Works and Escalators Works -EMSD;
• Code of Practice for Energy Efficiency of Lift and Escalator Installations - EMSD
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The relevant COPs for lifts & Escalators Works in Hong Kong
• Code of Practice Building Works For Lifts and Escalators -BA
• Code of Practice for Means of Access for Firefighting and Rescue - BA
• Code of Practice Fire Resisting Construction - BA
• Design Manual Barrier Free Access - BA
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The relevant COPs for lifts & Escalators Works in Hong Kong
• Code of Practice for Safety at Work (Lift and Escalator) -LD
• Guide on Safety in Lift Repair & Maintenance - LD
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The relevant COPs for lifts & Escalators Works in Hong Kong
• GUIDELINES on Safety of Lift shaft Works
(Volume 1 – During Construction Stage and before Handing over to lift
installation Contractor) - CIC
• GUIDELINES on Safety of Lift Shaft Works
(Volume 2 – During lift installation stage until of occupation permit and
handing over to developer) - CIC
• GUIDELINES on Safety of Lift Shaft Works
(Volume 3 – Throughout the occupation stage of building) - CIC
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Cap 327 & Cap 618
• The Lifts and Escalators Ordinance (Cap. 618) was enacted in April 2012
• Put into full operation on 17 December 2012 to replace
the repealed Lifts and Escalators (Safety) Ordinance
(Cap. 327) which was enacted in the 1960s.
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Chapter 327
Maintenance and Examination of Lifts and Escalators and Testing of Safety
Equipment
Section 19 Periodic maintenance of lifts and escalators (Schedule 5 Part 1 & Part 5)
The lift or escalator, all machinery and equipment connected therewith and the
safety equipment provided therefor to be cleaned, oiled and adjusted by a
registered lift contractor or a registered escalator contractor, as the case may
be, at intervals not exceeding one month.
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Chapter 327
Section 20 Periodic examination of lifts (Schedule 5 Part 2)
At intervals not exceeding 12 months, cause the lift to be thoroughly
examined by a registered lift engineer in order to determine whether the lift
and all machinery and equipment connected therewith is in safe working
order.
Section 21 Periodic examination of escalators (Schedule 5 Part 5)
At intervals not exceeding 6 months, cause the escalator to be thoroughly
examined by a registered escalator engineer in order to determine whether
the escalator and all machinery and equipment connected therewith is in
safe working order.
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Chapter 327Section 23 Periodic testing of safety equipment of lifts (Schedule 6)
(a) At intervals not exceeding 12 months, by the operation of the same without any load
in the lifts;
(b) At intervals not exceeding 5 years, by the operation of the same with full rated load
in the lift;
(c) At intervals no exceeding 5 years, by the operation of the overload device of the
same with a load in the car of the lift weighing between 90 per cent to 110 per cent of
the rated load; and
(d) At intervals not exceeding 5 years, by the operation of the brake when the car or
platform of the lift is travelling in the downward direction at tis rated speed with a load
weighting 125 per cent of the rated load for lifts designed and constructed in
accordance with BS 5655: Part 1 and weighing 110 per cent of the rated load for
other lifts
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Chapter 327
Section 24 Periodic testing of safety equipment of escalators
At intervals not exceeding 12 months, the owner of every escalator shall, in
addition the examination thereof required by section 22, cause the safety
equipment provided therefor to be tested by a registered escalator engineer by
the operation of the same without any load on the escalator
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Lifts and Escalators Ordinance (Chapter 618)
• Come into force and repealed the Cap327 since
17 December 2012
• Lifts and Escalators (General) Regulation
• Lifts and Escalators (Fees) Regulation
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Features of Cap618
• Increasing the penalty levels of offences (i.e. RC from
$50,000 to $100,000 & RLE/REE from $0 to $10,000 and
the maximum fine is $200,000 and max. imprisonment 12
months)
• Responsible Persons (“RPs”) who include with owners of a
lift/escalator and other person who have the management or
control of the lift/escalator
• Guidebook for Responsible Persons for lifts
• Guidebook for Responsible Persons for Escalators
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The ordinance ensures the safety of lift and escalator
1. Equipment compliance:
Safety components are required type approved by EMSD
2. Quality control:
Installation, maintenance, repair, alteration and demolition of
lifts/escalators are undertaken by RCs
RCs are required to notify EMSD in respect of undertaking
and subcontracting of lift/escalators work (i.e. except
installation or demolition works)
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3. RCs are required to attend to failures of emergency devices
of lifts within 4 hours when RCs aware of the failures
(Emergency devices include alarm system, emergency
lighting, intercommunication system, ventilation fan) – Under
the Lift and Escalator (General) Regulation section 8
4. If the failure of any emergency device cannot be rectified
within 24 hours, RC must within 24 hours notify EMSD in the
specified form
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5. Registration system:
RCs and REs are required to renew their registration every
5 years
A new registration system for lift/escalator workers (i.e. RWs)
REs and RWs are required to carry their registration cards
at works
Disciplinary actions can be taken registered persons who
have committed disciplinary offences
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6. Public monitoring
RP is required to notify EMSD and the RC within 24 hours if
incident occur
RCs are required to display a notice within 4 hours if
lift/escalator is suspended due to the incident
Incidents are included as the following:
• Death or injury involves a lift
• Failure of main drive system
• Breakage of suspension rope
• Failure of brake, overload device, safety equipment
• Failure of interlocking device for any door (i.e.
include with lift-way door or car door)
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Code of Practice on the Design and Construction of Lifts and Escalators
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Code of Practice on the Design and Construction of Lifts and Escalators
• The code is based on EN81-1, EN81-2 and EN-
115-1
• The first code is from 1993 edition and revised in
2000, 2010
• The code will be effective upon the day section 157
of the Cap 618
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Code of Practice for Lift Works and Escalator Works
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Code of Practice for Lift Works and Escalator Works
• The code give guidance on matters relating to the safety of
lifts and escalators;
• In particular on the works with installation, commissioning,
examination, maintenance, repair, alternation or demolition;
• The code has been consulted the trade on the proposed
contents of the works code
• The code sets out the min. industry standard in satisfying
the Ordinance
• The code had been made reference to the relevant safety
standards of the European Standards Institution
• The Code will be effective upon the day on section 157 of
the Cap 61826
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Code of Practice for Lift Works and Escalator Works
Section 3 - Overview of Duties:
• General duties of RPs
• General duties of RCs
• General duties of REs
• General duties of RWs
• General relationship between registered persons
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Code of Practice for Lift Works and Escalator Works
Section 4 – General Requirements:
• Type approval
• Change in design and construction
• Work to be carried by two or more lift workers
• Relationship of lift works or escalators with building works
• Fire safety measures in carrying out lift works or escalator works in
buildings with occupations
• Fire resisting construction requirements for lift shaft
• Work concerning the landing door or car door of a lift
• Working within a lift shaft
• Working on the top of a lift car
• Working in a lift pit
• Working in machinery spaces or pulley rooms
• General safety measures for carrying out escalator
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Code of Practice for Lift Works and Escalator Works
Section 5 - Specific Requirements Relating to Lift Works and Escalators Works:
• 5.1 General
• 5.2 Matters relating to installation of lifts or escalators
• 5.3 Examination of lifts or escalators upon completion of installation
• 5.4 Maintenance of lifts and escalators
• 5.5 Periodic examination of lifts or escalators
• 5.6 Major alterations
• 5.7 Thorough examination following major alterations
• 5.8 Demolition of lifts or escalators
• 5.9 Notification for subcontracting of lift works or escalators works
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Code of Practice for Lift Works and Escalator Works
6 Miscellaneous:
• Entering information into log-books
• Maintenance records to be kept by RCs
• O&M manuals and technical data
• Handling fault calls and safe release of trapped passengers
• Reportable incidents
• Posting of notice relating to incidents
• Incident investigations
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Code of Practice for Building Works for Lifts and Escalators 2011
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Code of Practice for Safety at Work (Lift and Escalator)
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Guide on Safety in Lift Repair & Maintenance
Only for Internal Circulation during CPD Lectures
Guidelines on Safety of Lift shaft Works (Volume 1 – During Construction Stage
and before Handing over to lift installation Contractor)
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Guidelines on Safety of Lift shaft Works (Volume 2 – During Lift Installation Stage
Until Issue of Occupation Permit and Handling over To Developer)
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Guidelines on Safety of Lift shaft Works (Volume 3 –Throughout the Occupation Stage of Building)
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Lift System
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Principle of Electric
Traction Lift System
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Safety Gear
Maximum Rated Speed
Type of Safety Gear
MaximumGovernor Tripping Speed
0.63 m/s Instantaneous type, except captive roller type
0.8 m/s
0.63 m/s Captive roller instantaneous type
1 m/s
1.0 m/s Instantaneous type with buffered
1.5 m/s
1.0 m/s Progressive type 1.5 m/s
Exceeding 1.0 m/s
Progressive type 1.25V + 0.25/V m/s
Table 3Relationship between Governor Tripping Speed,
Type of Safety Gear and Rated Speed
COP5.11.1 Part 1: The car shall be provided with a safety gear capable of operating in the downward direction and capable of stopping a car carrying the rated load, at the tripping speed of the overspeed governor , even if the suspension devices break, by gripping the guide rails, and of holding the car there
Instantaneous Type
Progressive Type
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Car safety Gear Tests
The following tests should be conducted with the car descending, with the brake open and the machine continuing to run till the ropes or become slack:
Progressive Type:
1.The safety gear shall operate correctly when engaging at rated speed with the rated load uniformity distribute in the lift car;
OR
2.The safety gear shall operate correctly when engaging at levelling or inspection speed with 125%/150% of the rated load uniformity in the lift car
Instantaneous Type:
The safety gear shall operate correctly when engaging at rated speed with the rated load uniformity distributed
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Overspeed Governor• Tripping speed of the overspeed governor for
the car safety gear shall occur at a speed at least equal to 115% of the rated speed and conform to the Table 3;
• Breaking load of the rope shall be related by a safety factor of a least 8 to the tensile force produced in the rope of the overspeed governor when tripping ;
• Nominal rope diameter of the safety rope at least 6 mm;
• Pitch diameter of the overspeed governor pulley and the nominal rope diameter shall be at least 30
• The breakage or slackening of the rope shall cause the motor to stop by means of an electrical safety device
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ManufactureRated Speed
m/s
Overspeed Governor Safety Gear
Tripping speed comply
with min. requirements﹝115%﹞
Tripping speed comply
with max. requirements﹝1.25V+0.25
/V﹞
Electrical Switch Tripped Speed
Manufacture Min. Manufacture Max Instantaneous Type
Progressive Type
(m/s) % (m/s) % (m/s) % (m/s) %
Fujitec 1 1.3 130 1.15 115 1.4 140 1.5 150 Progressive Type Yes Yes
Hitachi 1 1.25 125 1.15 115 1.31 131 1.5 150 Progressive Type Yes Yes
Otis 1 1.28 128 1.15 115 1.38 138 1.5 150 Progressive Type Yes Yes
Fujitec 1.25 1.71 137 1.44 115 1.88 150 1.76 141 Progressive Type Yes No
Mitsubishi 1.25 1.5 120 1.44 115 1.67 134 1.76 141 Progressive Type Yes Yes
Fujitec 1.75 2 114 2.01 115 2.33 133 2.33 133 Progressive Type No Yes
Hitachi 1.75 2.18 125 2.01 115 2.28 130 2.33 133 Progressive Type Yes Yes
Fujitec 2 2.23 112 2.30 115 2.48 124 2.63 131 Progressive Type No Yes
Fujitec 2 2.33 117 2.30 115 2.6 130 2.63 131 Progressive Type Yes Yes
Hitachi 2 2.48 124 2.30 115 2.58 129 2.63 131 Progressive Type Yes Yes
Hitachi 2.5 3.11 124 2.88 115 3.18 127 3.23 129 Progressive Type Yes Yes
Otis 2.5 2.88 115 3.66 146 3.23 129 Progressive Type No
Case StudyFor reference only
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Brake• The brake can sustain the static car in
the lower part of its travel at its rated speed, with the 125% of the rated load (passenger/general freight lifts) or 150%of the rated load (vehicle lifts/industrial truck loaded freight lifts) of the rated speed; (test criterion)
• In these conditions the retardation of the car shall not exceed resulting from operation of the safety gear or stopping on the buffer;
• If one of the components was not working on the brake drum a sufficient braking effort to slow down the car when containing with rated load;
• Any solenoid plunger is considered to be a mechanical part, any solenoid coil is not.
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Suspension Ropes
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Rope Traction
1. The car shall be maintained at floor level without slip when load to 125%/150%;
2. It shall be ensured that any emergency braking causes the car, whether empty or with rated load, to decelerate with a value not exceeding the setting of the buffer
3. It shall not be possible to raise the empty car when counterweight is resting on the buffer
Traction Check:1. The empty car could be travelling upwards at rated speed;
2. The car can be stopped with 125% of the rated speed when travelling downwards
in the lower part of the lift well at rated speed;
3. With the counterweight resting on its fully compressed buffers, it is not be
possible to raise the empty car
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Energy Accumulation Buffers• The total possible stroke of the buffers shall
be at least equal to twice the gravity stopping distance corresponding to 115%of the rated speed, (i.e. 2 x 0.0674 V2
meters). In any cases it shall not be less than 65 mm;
• Buffer shall be designed to cover the stroke defined above under a static load of between 2.5 to 4 times the sum of the mass of the car and it rated load (or the mass of the counterweight);
• Energy accumulation type buffers with buffered return movement may only be used if the rated speed of the lifts does not exceed 1.6 m/s.
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Energy Dissipation Type Buffers• Energy dissipation type buffers may be used
whatever the rated speed of the lift;
• Total possible stroke of the buffers shall be at least equal to the gravity stopping distance corresponding to 115% of the rated speed, i.e. 0.067V2 m.
Reduced Buffer Stroke
When the retardation of the lift at the ends of its travel is monitored:
a. 50% of the stroke with the speed not exceed 4 m/s and the stroke does not less than 420 mm;
b. 33 1/3% of the stroke with the speed exceeds 4m/s and the stroke shall not less than 540 mm
Buffer Tests:a) The car shall be brought into contact with the buffers at rated load at rated
speed, or at a speed for which the stroke of the buffers has been calculated (i.e. . 2 x 0.0674 V2 )
b) The buffers shall recover automatically after operation
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Final limit Switch
• Final limit switch shall be set to
function as close as possible to the
terminal floors, without risk of
accident operation;
• They shall operate before the car (or
counterweight if there is one) comes
into contact with the buffers. The
action of the final limit switches shall
be maintained whilst the buffers are
compressed
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Slowdown of the lift in the case of Reduced Stroke Buffers
• The devices shall check that the
slowdown of the lift car is effective
before arrival at terminal landings;
• If the slowdown is not effective these
devices shall cause the car speed to
be reduced in such a way that, if the
car comes into contact with the
buffers, the striking speed shall not
exceed that for which the buffers were
designed
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Overload Protective Device
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4..2.4 Overload Device:
• Fail safe design;
• Not be damaged by excessive
overloading;
• Operate in exceed 10% or more
• Preventing door closing and
movement
• Audible and visual signals
Cap 618:Load weight in the car shall be between
90% and 110% of rated load
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Protection during door operations
4.6 of pt1-COP
• Automatic power operated horizontally sliding doors:
• Prevent the door closing shall not exceed 150 N when the door closing in 1/3 travel distance and average closing speed shall not exceed 10 J
• A sensitive protective device shall automatically initiate re-opening:
‒ Effect of the device may be neutralized at last 50 mm of travel
‒ In case of make the protective device inoperative after a fixed period of time, the kinetic energy shall not exceed 4J with audible alarm
‒ A single beam light ray alone is considered insufficient
‒ Re-open button shall be provided on the COP
• The detection device shall be positioned at a height of between 500 mm to 600 mm above the floor of the lift car. (Barrier Free Access 2008/79(4))
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A car door locking device4.7 of pt1-COP Car door locking device
• Shall be certify a Type Test Certificate
4.9 of pt1-COP Locking of the car door
• Every car door shall be mechanically
locked by at least 7 mm that it can
only be opened by in the unlocking
zone;
• If horizontal distance between the
wall of the well and the sill or
entrance frame is over 150 mm, the
locking shall be proved by electrical
safety device.
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Levelling
BS5655-6: 2002
a. AC1 between ±25 mm and ± 40 mm
b. AC2 between ±10 mm and ± 20 mm
c. ACVV and DCVV between ±10 mm
d. VVVF between ±10 mm and ± 5 mm
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Lift well and Enclosure1.1 of pt1-COP General Provisions
• Car and counterweight shall be enclosed in a lift well
• Comply with fire resisting construction (FRP – 2hrs.)
• When the lift well is required to protect of the building
against spread of fire, it shall be totally enclosed and
comply with Building (Planning) Regulations
• If not, the landing door size shall either cover of full
height or be minimum height of 3.5 m and enclosure
shall be of minimum 2.5 m with minimum horizontal
of 0.5 m to moving parts of lift
1.6 of pt1-COP Exclusive Use of the Lift Well
• The well shall be exclusively for the lift.
• It shall not contain cables or devices etc., other
than for lift and for telecommunication at the lift car;
• Nor shall it be fitted with any fire sprinklers
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Escalator
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Construction of Escalator
θ
θ is the inclined angle of escalator (i.e. 300 or 350)
H is the height of the escalator
H
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Truss
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• The support structure shall be
designed in a way that it can support
the dead weight of the escalator plus
a passenger weight of 5,000 N/m2
(Load Weight);
• Load carrying weight = nominal width
of step (Z1) x distance between
support (l1);
• Base on passenger weight, the
maximum calculated or measured
deflection shall not exceed 1/750 of
the distance between supports l1,
The deflection value shall be reduced
to 1/1000 of l1 for public service
escalator
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Dimension of escalator
58
Nominal Width (m) Number of carrying passengers
600 1
800 1.5
1000 2
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Theoretical Capacity
59
Nominal Width (m)
Rated Speed (m/s)
0.50 0.65 0.75
0.6 4500 persons/h 5850 persons/h 6750 persons/h
0.8 6750 persons/h 8775 persons/h 10125 persons/h
1.0 9000 persons/h 11700 persons/h 13500 persons/h
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Safety Device for escalator
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Safety device –Slagging 1. Slagging of steps
2. Slagging of step rollers
3. Slagging of step chain rollers
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Skirt Panel Safety Device
Rise Number of skirting safety device at provided at each of the inclined section
≤ 6 m6 m < Rise ≤ 7.5 m7.5 m < Rise ≤ 9 m
123
The number of electrical safety device required for an escalator of rise exceeding 9 m shall be so calculated accordingly
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Comb Plate Safety Device
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Comb
Comb
Comb PlateLess than 4mm
Measurement gauge
The comb should be engaged into the comb at
least 6mm – COP part 4 – 7.3.1
Less than 4 mmCOP Part 4 – 7.3.2
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Handrail Entry Inlet Safety Switch
65
To prevent the pinching of fingers, hands or other objects – COP Part 4 –3.5.3
The dimension shall be not less than 0.10 m and not exceed 0.25 m COP Part 4 – 3.5.1
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No Load Downward Stopping Distance
Rated Speed Stopping Distance
0.5m/s min 0.20m and max. 1.00m
0.65m/s min 0.30m and max. 1.30m
0.75m/s min 0.40m and max.1.70m
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Auxiliary Brake
• Escalator (excluding non-inclined passenger conveyors) shall be
equipped with auxiliary brake acting immediately, or via gears or
shaft, on the main driving shaft in the condition as the following:
1. The coupling of the operational brake and the driving wheels of the steps, pallet or
the belt is not accomplished by shafts or gear wheels; or
2. The operational brake is not an electro-mechanical brake; or
3. The rise exceed 6 m; or
4. They are public service escalators
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Operation of Auxiliary Brake
1. Before the speed exceeds a value of 1.4 times the rated speed by
the operation of the overspeed governor or other speed control
devices;
2. By the time the steps and pallet or the belt change from the
present direction of motion; or
3. In the event of the failure of the coupling of the operational brake
and the driving wheels of the steps, pallet or the belt, in case the
coupling is not accomplished by shafts or gear wheels
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Landing Area
• At the landings of the escalators a
sufficient unrestricted area shall be
available to accommodate
passengers;
• The width of the unrestricted area shall
at least correspond to the distance
between the handrail centerlines;
• The depth shall be at least 2.50m
measured from the end of the
balustrade;
• It is permissible to reduce it to 2.00 m
if the width of the unrestricted area is
increased to reduce at least double
size.
And the clear Height shall be at least 2.3 m
2.0 m / 2.5 m
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Clearance between Balustrade and Adjacent Rail/Wall
• The maximum clearance between the balustrade exterior paneling and any guard rail/wall erected adjacent to the escalator shall not more than 100 mm.
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Accident
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Accident
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Accident
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Accident