oSIST prEN 81-77:2020

Safety rules for the construction and installations of lifts - Particular applications for passenger and goods passenger lifts - Part 77: Lifts subject to seismic conditions

This document specifies the special provisions and safety rules for passenger and goods passenger lifts where these lifts are installed in buildings and constructions intended to withstand seismic events in compliance with EN 1998 1:2004 (Eurocode 8).
This document does not introduce any specific provisions and safety rules for lifts when ad ≤ 1 m/s2 as defined in Annex A.
This document does not address other risks due to seismic events (e.g. fire, flood, explosion).
This document is not applicable to lifts installed before the date of its publication.

Sicherheitsregeln für die Konstruktion und den Einbau von Aufzügen - Besondere Anwendungen für Personen- und Lastenaufzüge - Teil 77: Aufzüge unter Erdbebenbedingungen

Dieses Dokument legt die besonderen Vorkehrungen und Sicherheitsregeln für Personen- und Lastenaufzüge fest, wenn diese Aufzüge dauerhaft in Gebäuden eingebaut sind, die EN 1998-1:2004 (Eurocode 8) entsprechen.
Dieses Dokument führt keine zusätzlichen besonderen Festlegungen und Sicherheitsregeln für Aufzüge nach Anhang A, ein, wenn ad ≤ 1 m/s2.
Dieses Dokument behandelt andere mit Erdbebenereignissen einhergehende Risiken (zum Beispiel Brand, Überflutung, Explosion) nicht.
Dieses Dokument gilt nicht für Aufzüge, die vor der Veröffentlichung installiert wurden.

Règles de sécurité pour la construction et l'installation des élévateurs - Applications particulières pour les ascenseurs et les ascenseurs de charge - Partie 77 : Ascenseurs soumis à des conditions sismiques

Le présent document spécifie les dispositions spéciales et les règles de sécurité relatives aux ascenseurs et ascenseurs de charge installés dans des bâtiments et constructions destinés à résister aux événements sismiques qui sont conformes à l’EN 1998 1:2004 (Eurocode 8).
Le présent document n’introduit pas de dispositions ni de règles de sécurité spécifiques pour les ascenseurs lorsque ad ≤ 1 m/s2 tel que défini dans l’Annexe A.
Le présent document ne traite pas des autres risques associés aux événements sismiques (par exemple incendie, inondation, explosion).
Le présent document n’est pas applicable aux ascenseurs installés avant sa date de publication.

Varnostna pravila za konstruiranje in vgradnjo dvigal (liftov) - Posebne izvedbe osebnih in tovorno-osebnih dvigal - 77. del: Dvigala (lifti) za potresne razmere

General Information

• Status: Not Published
• Public Enquiry End Date: 20-Dec-2020
• ICS: 91.120.25 - Seismic and vibration protection
• ICS: 91.140.90 - Lifts. Escalators
• Technical Committee: DTN - Lift and transport appliances
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 21-Jan-2022
• Due Date: 11-Mar-2022
• Directive: 2014/33/EU - Directive 2014/33/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to lifts and safety components for lifts (recast)
• Mandate: M/549 - [C(2016)5884] Lifts and safety components for lifts
• Ref Project: FprEN 81-77 - Safety rules for the construction and installations of lifts - Particular applications for passenger and goods passenger lifts - Part 77: Lifts subject to seismic conditions

RELATIONS

• Revised: SIST EN 81-77:2019 - Safety rules for the construction and installations of lifts - Particular applications for passenger and goods passenger lifts - Part 77: Lifts subject to seismic conditions
• Effective Date: 27-Nov-2019

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 81-77:2020
01-december-2020
Varnostna pravila za konstruiranje in vgradnjo dvigal (liftov) - Posebne izvedbe
osebnih in tovorno-osebnih dvigal - 77. del: Dvigala (lifti) za potresne razmere

Safety rules for the construction and installations of lifts - Particular applications for

passenger and goods passenger lifts - Part 77: Lifts subject to seismic conditions

Sicherheitsregeln für die Konstruktion und den Einbau von Aufzügen - Besondere
Anwendungen für Personen- und Lastenaufzüge - Teil 77: Aufzüge unter
Erdbebenbedingungen

Règles de sécurité pour la construction et l'installation des élévateurs - Applications

particulières pour les ascenseurs et les ascenseurs de charge - Partie 77 : Ascenseurs

soumis à des conditions sismiques
Ta slovenski standard je istoveten z: prEN 81-77
ICS:
91.120.25 Zaščita pred potresi in Seismic and vibration
vibracijami protection
91.140.90 Dvigala. Tekoče stopnice Lifts. Escalators
oSIST prEN 81-77:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 81-77:2020
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oSIST prEN 81-77:2020
DRAFT
EUROPEAN STANDARD
prEN 81-77
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2020
ICS 91.140.90; 91.120.25 Will supersede EN 81-77:2018
English Version
Safety rules for the construction and installations of lifts -
Particular applications for passenger and goods passenger
lifts - Part 77: Lifts subject to seismic conditions

Règles de sécurité pour la construction et l'installation Sicherheitsregeln für die Konstruktion und den Einbau

des élévateurs - Applications particulières pour les von Aufzügen - Besondere Anwendungen für

ascenseurs et les ascenseurs de charge - Partie 77 : Personen- und Lastenaufzüge - Teil 77: Aufzüge unter

Ascenseurs soumis à des conditions sismiques Erdbebenbedingungen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 10.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 81-77:2020 E

worldwide for CEN national Members.
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oSIST prEN 81-77:2020
prEN 81-77:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

0 Introduction ...................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 List of significant hazards ............................................................................................................................ 7

5 Safety requirements and/or protective measures ............................................................................. 7

5.1 General ................................................................................................................................................................ 7

5.2 Lift well ............................................................................................................................................................... 7

5.3 Machinery and pulley spaces ...................................................................................................................... 8

5.4 Car ......................................................................................................................................................................... 9

5.5 Counterweight or balancing weight ...................................................................................................... 10

5.6 Suspension and compensation means .................................................................................................. 11

5.7 Precaution against oil spillage ................................................................................................................ 11

5.8 Guide rail system .......................................................................................................................................... 11

5.9 Machinery and other lift equipment ..................................................................................................... 13

5.10 Electric installations and appliances .................................................................................................... 13

6 Verification of the safety requirements and / or protective measures .................................... 15

7 Information for use ..................................................................................................................................... 17

Annex A (normative) Seismic lift categories ................................................................................................... 18

Annex B (informative) General information and determination of the design acceleration ........ 19

Annex C (informative) Primary wave detection system ............................................................................. 21

Annex D (informative) Proof of guide rails ...................................................................................................... 22

Annex ZA (informative) Relationship between this European Standard and the essential

requirements of Directive 2014/33/EU aimed to be covered ..................................................... 27

Bibliography ................................................................................................................................................................. 29

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oSIST prEN 81-77:2020
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European foreword

This document (prEN 81-77:2020) has been prepared by Technical Committee CEN/TC 10 “Lifts,

escalators and moving walks”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of EU Directive(s).

For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this

document.
This document will supersede EN 81-77:2018.

In comparison with the previous edition, the following significant changes have been made:

— all externally referenced standards have now been dated;
— general editorial corrections since the last publication;
— visual indication of seismic mode;
— replace mass P with P in proof of guide rails (Annex D);

— a new Annex ZA has been developed in order to be aligned with the requirements of the EU

Commission Standardization Request “M/549 C(2016) 5884 final”.
No technical changes have been made during this revision.

The content of this document provides the enhanced design rules, calculations, examinations and tests

for lifts where protection is needed for seismic events.

This document is intended to be used in conjunction with the EN 81-20:2020, which gives the

requirements for passenger and goods passenger lifts.

This document is part of the EN 81 series of standards. The structure of the EN 81 series is described in

CEN/TR 81-10:2008.
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0 Introduction
0.1 General
This document is a Type C Standard as stated in EN ISO 12100:2010.

The machinery concerned and the extent to which hazards, hazardous situations and events are covered,

are indicated in the scope of this standard.

When requirements of this type-C standard are different from those which are stated in type-A or type-B

standards, the provisions of this type-C standard take precedence over the provisions of the other

standards, for machines that have been designed and built according to the provisions of this type-C

standard.
0.2 General remarks

0.2.1 The object of this standard is to define additional safety rules related to passenger and goods lifts

with a view to safeguarding persons and objects against the risks described below associated with the

use, maintenance, inspection and emergency operation of lifts subject to seismic conditions.

0.2.2 The aim of this document is to:
— avoid loss of life and reduce the extent of injuries;
— avoid people trapped in the lift;
— avoid damage;
— avoid environmental problems related to oil leakage;
— reduce the number of lifts out of service.
0.3 Principles

Risk analysis, terminology and technical solutions have been considered taking into account the methods

of EN ISO 12100:2010 and EN ISO 14798:2013.
0.4 Assumptions

It is assumed that information has been exchanged to determine the design acceleration (a ) to be

considered and the most effective position of the seismic detection system, if any, and of the primary

wave detection system, if any.
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1 Scope

This document specifies the special provisions and safety rules for passenger and goods passenger lifts

where these lifts are installed in buildings and constructions intended to withstand seismic events in

compliance with EN 1998-1:2004 (Eurocode 8).

This document does not introduce any specific provisions and safety rules for lifts when a ≤ 1 m/s as

defined in Annex A.

This document does not address other risks due to seismic events (e.g. fire, flood, explosion).

This document is not applicable to lifts installed before the date of its publication.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

EN 81-20:2020, Safety rules for the construction and installation of lifts - Lifts for the transport of persons

and goods - Part 20: Passenger and goods passenger lifts

EN 81-50:2020, Safety rules for the construction and installation of lifts - Examinations and tests - Part 50:

Design rules, calculations, examinations and tests of lift components

EN 81-72:2020, Safety rules for the construction and installation of lifts - Particular applications for

passenger and goods passenger lifts - Part 72: Firefighters lifts

EN ISO 12100:2010, Safety of machinery - General principles for design - Risk assessment and risk reduction

(ISO 12100:2010)

ISO 7465:2007, Passenger lifts and service lifts — Guide rails for lift cars and counterweights — T-type

3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN ISO 12100:2010, EN 81-20:2020

and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
snag point
point of interference between flexible moving elements and fixed elements

Note 1 to entry: Examples of flexible moving elements are ropes, chains, travelling cable.

Note 2 to entry: Examples of fixed elements are guide rail brackets, guide rail clip bolts, fishplates, vanes, and

similar devices.
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3.2
design acceleration

horizontal acceleration to be used for calculation of forces acting on lift systems and arising from seismic

events
Note 1 to entry: See Annex B.
3.3
seismic lift categories

categories in which lifts have been divided, taking into account the design acceleration (a )

Note 1 to entry: Table A.1 shows the seismic lift categories.
3.4
primary wave
compressional wave that is longitudinal in nature

Note 1 to entry: Earthquake advance warning is possible by detecting the non-destructive primary waves that

travel more quickly through the Earth's crust than do the destructive secondary waves (shear wave that is

transverse in nature, its motion being perpendicular to the direction of wave propagation). The amount of advance

warning depends on the delay between the arrival of the primary wave and other destructive waves, generally in

the order of seconds for distant, large quakes.

Note 2 to entry: Secondary waves move through solids, unlike surface waves. They are destructive and arrive

later than primary waves.
3.5
seismic trigger level
seismic acceleration which activates a seismic detection system
3.6
seismic mode
special mode in which the lift operates after detection of seismic trigger level
3.7
seismic stand-by mode

special mode in which the lift operates after detection of primary wave without the activation of the

seismic detection system
3.8
normal operation

operation mode in which the lift operates when not in seismic mode or in seismic stand-by mode

3.9
retaining device

mechanical device securely fixed to a structural member of the lift car, counterweight or balancing weight

frame, designed to retain the lift car and counterweight (balancing weight) within its guide rails during

seismic activity
3.10
expansion joint

assembly designed to safely absorb the heat-induced expansion and contraction of various construction

materials, to absorb vibration, or to allow movement due to ground settlement or earthquakes

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4 List of significant hazards

This clause contains all the significant hazards, hazardous situations and events, as far as they are dealt

with in this standard, identified by risk assessment as significant for this type of machinery and which

require action to eliminate or reduce the risk (see Table 1).
Table 1 — List of significant hazards
No Hazards Relevant clauses
as listed in EN ISO 12100:2010, Annex B
Acceleration, deceleration 5.4.1, 5.5, 5.8.2, 5.3, 5.9
Angular parts 5.2
Approach of a moving element to a fixed part 5.4.2, 5.5
Moving elements 5.4.3, 5.6.2
Rotating element 5.6.1, 5.6.2
2 Failure of the power supply 5.10.2, 5.10.3.5
Pollution 5.7, 5.9
Failure of the control circuit 5.10.3.4, 5.10.3.5
5 Safety requirements and/or protective measures
5.1 General

Passenger and goods passenger lifts shall comply with the safety requirements and/or protective

measures of the following clauses. In addition, lifts shall be designed according to the principles of

EN ISO 12100:2010 for relevant but not significant hazards that are not dealt with by this document.

If not differently specified, the following requirements apply to Seismic lift category 1, 2 and 3.

5.2 Lift well

In order to prevent that suspension ropes, overspeed governor ropes, travelling cables, compensation

ropes and chains, swaying in the well get entangled with fixed equipment, snag points created by

brackets, sills, devices and other equipment mounted in the well shall be protected according to Table 2.

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Table 2 — Protection of snag points
Height Horizontal distance Lift parts Protective measures Remarks
of the between snag
well points and lift parts
≤ 20 m Not necessary
< 900 mm Travelling cables a protection wire in Required if any
the corner of the rail portion of the loop
bracket or other snag is smaller than
points near the 900 mm from a
travelling cables snag point
< 750 mm Compensating a protection wire in Full travel
Chain(s) the corner of the rail
bracket or other snag
Compensating
points
rope(s)
> 20 m
Counterweight
overspeed governor
≤ 60 m
rope
< 500 mm Car overspeed a protection wire in Full travel
governor rope the corner of the rail
bracket or other snag
points
< 300 mm Suspension ropes a protection wire in Full travel
the corner of the rail
bracket or other snag
points

> 60 m Protect all snag points Travelling cables a protection wire in Full travel

independently from the corner of the rail
Compensating
horizontal distance bracket or other snag
Chain(s)
points
Compensating
rope(s)
Counterweight
overspeed governor
rope
Car overspeed
governor rope
Suspension ropes
5.3 Machinery and pulley spaces

Where buildings are designed with expansion joints subdividing the structure into dynamically

independent units, all the lift machinery including the landing entrances and the well of the lift shall be

located on the same side of an expansion joint.
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5.4 Car
5.4.1 Mass of the car for lift design calculations

For lift design calculations, the forces generated by the design acceleration (a ) shall be calculated taking

into account:

— for passenger lifts, the mass of the car plus 40 % of the rated load evenly distributed;

— for goods passenger lifts, the mass of the car plus 80 % of the rated load evenly distributed.

5.4.2 Car retaining devices

For lifts in lift categories 2 and 3, the car frame shall be provided with upper and lower retaining devices

able to hold the car frame on its guide rails.

The retaining devices shall be placed in such a way to distribute loads in a similar way as the guide shoes.

The retaining devices shall either be integrated or mounted close to the fixing of the guide shoes.

When the car is centre located between the guide rails, the clearances d , d and d (Figure 1 a)) between

1 2 3

the retaining device and the guide rail shall not exceed 5 mm and the dimensions chosen shall not cause

accidental tripping of the safety gear during an earthquake.

The depth of the retaining device (z ) shall be limited to avoid collision with guide rail attachments or

other fixed devices, but long enough to guarantee a minimum overlapping length between retaining

devices and the guide rail blade during an earthquake. The required depth of the retaining devices is also

correlated with the type of guide rail through the allowable deflection of the guide rail (see 5.8.2).

During an earthquake, the minimum overlapping length (z ) between retaining devices and the guide rail

blade shall be at least 5 mm (Figure 1 b)).

The car structure and retaining devices shall withstand the loads and forces imposed on them including

forces generated by the design acceleration (a ), without permanent deformation.
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a) Nominal position and clearance of retaining device b) Minimum required overlapping length of retaining

device during earthquake
Key
d1 clearances between the retaining device and the guide rail
d clearances between the retaining device and the guide rail
d3 clearances between the retaining device and the guide rail
x guide rail x-axis
y guide rail y-axis
z depth of the retaining device
z2 blade height
z3 overlapping length of retaining device during earthquake (≥5 mm)
Figure 1 — Retaining device
5.4.3 Car door locking devices

To prevent the opening of car doors, for lifts in Seismic lift category 2 and 3, the car doors shall be

provided with a car door locking device which shall be designed and operate as described in

EN 81-20:2020, 5.3.9.2.
5.5 Counterweight or balancing weight

The counterweight or balancing weight shall be provided with upper and lower retaining devices able to

hold the frame in between its guide rails.

The retaining devices shall be placed in such a way to distribute loads in a similar way as the guide shoes.

The retaining devices shall either be integrated or mounted close to the fixing of the guide shoes.

The clearances d , d and d (Figure 1 a)) between the retaining devices and the guide rails shall not

1 2 3

exceed 5 mm. When a safety gear is present, the dimensions chosen for the clearances d , d and d shall

1 2 3
not cause accidental tripping of the safety gear.
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During an earthquake, the minimum overlapping length (z ) between retaining devices and the guide rail

blade side shall be not less than 5 mm (Figure 1 b)).

The counterweight or balancing weight structure and retaining devices shall withstand the loads and

forces imposed on them including forces generated by the design acceleration (a ), without permanent

deformation.

The strength of the retaining devices and the counterweight frame or balancing weight frame shall be

calculated taking into account the vertical mass distribution of the assembly of the counterweight frame

or balancing weight including filler weights.

If the counterweight or the balancing weight incorporates filler weights, necessary measures shall be

taken to prevent their movement outside the frame considering the design acceleration value.

5.6 Suspension and compensation means
5.6.1 Protection for traction sheaves, pulleys and sprockets

The devices for preventing the ropes from leaving the grooves of traction sheaves and pulleys shall

include one retainer within 15° of the points where the ropes enter and leave the pulleys and at least one

intermediate retainer every 90° of the angle of wrap. The strength and stiffness of the retainers and their

distance to the traction sheaves and pulleys compared to the diameter of the ropes shall be such that they

are effective.

The devices for preventing the chains from leaving the sprockets shall include one retainer within 15° of

the points where the chains enter and leave the sprockets.
5.6.2 Compensation means

Compensation means provided according to EN 81-20:2020, 5.5.6 shall be guided in the pit in order to

limit them from swaying and reaching snag points.
5.7 Precaution against oil spillage

Hydraulic lifts shall be provided with a rupture valve. The rupture valve shall comply with the

requirements of EN 81-20:2020, 5.6.3.
5.8 Guide rail system
5.8.1 General

The guide rails, their joints and attachments shall comply with the requirements of EN 81-20:2020, 5.7

and they shall also withstand the loads and forces generated by the design acceleration (a ).

Where retaining devices are provided, car and counterweight or balancing weight retaining devices shall

be used as frame supporting points in the guide rail verification.
NOTE Annex D describes an example method for selecting guide rails.
5.8.2 Permissible stresses and deflections during seismic event

5.8.2.1 Where retaining devices are not provided, the maximum permissible deflections of the car

guide rail system shall comply with the requirements of EN 81-20:2020, 5.7, taking into account the load

and the forces generated by the lift system including the forces generated by the design acceleration (a ).

5.8.2.2 Where retaining devices are provided, the requirements stated below shall be fulfilled. The

safety factors for guide rails shall satisfy Table 3.
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Table 3 — Safety factors for guide rails
Elongation (A ) Safety factor
A ≥ 12 % 1,8
8 % ≤ A < 12 % 3,0

For guide rails in accordance with ISO 7465:2007, the values of Table 4 shall be used.

Table 4 — Permissible stresses σ
perm
Rm (Tensile strength of guide rail) (N/mm ) 370 440 520
σperm (Permissible stresses) (N/mm ) 205 244 290

The maximum permissible deflection of car or counterweight (balancing weight) guide rail in y direction

(see Figure 2) shall be such that the overlapping length between the blade of the guide rail and the

retaining devices is not less than 5 mm (see Figure 1 b)).

The maximum permissible deflection of the car guide rail, counterweight or balancing weight guide rail

in x direction (see Figure 2) shall also be applied in y direction.

The maximum permissible deflection includes the deflections of the guide rail, it's fixing brackets and

separation beams, if used. For T-profile guide rails the maximum permissible deflection in millimetres

(see Figure 1) is:
δ = z — 2d – 5 (1)
perm 1 3
but never more than 40 mm.
Key

Fx force exerted to the guide rail by the guide shoes or by the retaining devices in the x-axis

Fy force exerted to the guide rail by the guide shoes or by the retaining devices in the y-axis

x-x guide rail x-axis
y-y guide rail y-axis
Figure 2 — Guide rail axis and forces
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5.9 Machinery and other lift equipment

All machinery, pulleys and associated overhead beams and supports, rope attachments, overspeed

governor, tension pulleys and compensation rope tension devices shall be designed and anchored to

prevent overturning and displacement as a result of the forces imposed on them including forces

generated by the design acceleration (a ).

For hydraulic lifts where rigid pipe is used, it shall use flexible pipe at the end of each rigid length.

5.10 Electric installations and appliances
5.10.1 Electric installations in the lift well

The fixing of landing switch devices or final limit switches, vanes or similar devices fixed in the well shall

be designed and installed to withstand the loads and forces imposed on them including forces generated

by the design acceleration (a ). In addition, the devices mentioned above shall be protected against

damage caused by ropes and cables swaying in the well.
5.10.2 Behaviour of the lift in case of failure of the mains power supply

For lifts in Seismic lift category 2 and 3, in order to avoid people to be trapped in the car in case of failure

of the normal power supply, the lift has to be able to move automatically the car to the next landing in up

or down direction.
At landing the lift shall operate as described below:

a) a lift with automatic power operated doors, when parked at a landing, shall open the doors, remove

the lift from normal operation and keep the door open;

b) for a lift with manually operated doors, when the car arrives at the designated landing, its door(s)

shall be unlocked and the lift removed from normal operation.

Where the lift is parked with doors closed, a means shall be provided to open the doors (even with the

electrical power on) enabling the rescue service to check whether the car is present and persons are not

trapped.

The automatic dispatch to the lowest landing as defined in EN 81-20:2020, 5.12.1.10 a) shall be rendered

inoperative.

The behaviour of the lift in case of failure of the normal power supply shall not override any of the

following:
— the electric safety devices;
— the inspection operation (EN 81-20:2020, 5.12.1.5);
— the emergency electrical operation (EN 81-20:2020, 5.12.1.6);
— the firefighters lift switch (EN 81-72:2020, 5.8.1).
5.10.3 Seismic detection system

5.10.3.1 A seismic detection system shall be provided for lifts with counterweight or balancing weight

in Seismic lift category 3.
NOTE For guidance on an additional primary wave detection system, see Annex C.
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5.10.3.2 Where the seismic detection system is used exclusively to send information to the lift it shall

be placed:
— in the pit of the lowest lift in the building, or

— in another location in the lower part of the lift well, in case of expected interference with other

vibration sources.
5.10.3.3 The seismic detection system shall comply with the following specifi
...