EN 1004-1:2020

SLOVENSKI STANDARD
01-januar-2021
Nadomešča:
SIST EN 1004:2005
Pomični delovni odri na kolesih iz predizdelanih tipskih elementov - 1. del:
Materiali, mere, obtežbe in varnostne zahteve
Mobile access and working towers made of prefabricated elements - Part 1: Materials,
dimensions, design loads, safety and performance requirements
Fahrbare Arbeitsbühnen aus vorgefertigten Bauteilen - Werkstoffe, Maße,
Lastannahmen und sicherheitstechnische Anforderungen
Tours d'accès et de travail roulantes en éléments préfabriqués - Matériaux, dimensions,
charges de calcul et exigences de sécurité
Ta slovenski standard je istoveten z: EN 1004-1:2020
ICS:
91.220 Gradbena oprema Construction equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 1004-1
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2020
EUROPÄISCHE NORM
ICS 91.220 Supersedes EN 1004:2004
English Version
Mobile access and working towers made of prefabricated
elements - Part 1: Materials, dimensions, design loads,
safety and performance requirements
Échafaudages roulants en éléments préfabriqués - Fahrbare Arbeitsbühnen aus vorgefertigten Bauteilen -
Partie 1 : Matériaux, dimensions, calculs de charge, Werkstoffe, Maße, Lastannahmen und
exigences de performance et de sécurité sicherheitstechnische Anforderungen
This European Standard was approved by CEN on 14 March 2020.

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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists 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.
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. EN 1004-1:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Classification . 9
4.1 Load classes . 9
4.2 Access classes . 9
4.3 Height classes . 9
5 Designation. 10
6 Materials . 10
7 General requirements . 10
7.1 General . 10
7.2 Dimensions . 12
7.3 Openings within platforms . 12
7.4 Side protection . 12
7.5 Castor wheels . 14
7.6 Access to platforms . 15
7.7 Means for stabilizing . 18
7.8 Connections . 18
7.9 Working and access platform units . 19
7.10 Erection and dismantling . 19
7.11 Requirements for mobile access towers less than 2 m working platform height . 19
8 Requirements for structural design . 20
8.1 General . 20
8.2 Characteristic actions on the complete structure including its parts . 20
8.3 Characteristic actions on parts of the structure . 21
8.4 Deflections . 24
9 Structural design . 24
9.1 Basic design principle . 24
9.2 Structural analysis . 25
9.3 Verification . 28
9.4 Positional stability . 30
10 Tests . 31
11 Instruction manual . 31
12 Marking . 31
12.1 Components . 31
12.2 Manufacturer's label . 32
13 Assessment . 32
Annex A (normative) Stiffness test on complete tower structure . 33
Annex B (informative) A-deviations . 36
Annex C (informative) Reduction of the wind load to equal members being upwind . 37
Bibliography . 40

European foreword
This document (EN 1004-1:2020) has been prepared by WG4 “Mobile access towers” under the
direction of Technical Committee CEN/TC 53 “Temporary works equipment”, the secretariat of which is
held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by May 2021, and conflicting national standards shall be
withdrawn at the latest by November 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 1004:2004.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: 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 the
United Kingdom.
Introduction
The development of mobile access and working towers systems is from the following two roots:
— scaffold manufacturers placed prefabricated unanchored scaffolds on four legs and castors;
— ladder manufacturers began to construct mobile access towers with light-weight ladders using
aluminium frames and castors.
Taking this into account, CEN/TC53 decided in 1980 to standardize the manufacture of mobile access
and working towers in parallel with the European standardization of prefabricated service and working
scaffolds EN 12810-2 and EN 12811-3.
For materials, this document refers only to valid documents. However, a large stock of equipment made
of materials conforming to documents no longer valid is in use. This document does not cover this
equipment.
Attention is drawn to the requirements of the European Council Directive 2009/104/EC (provisions
concerning the use of work equipment provided for temporary work at a height).
The average height of people continues to increase and that consideration will have to be given in later
revisions to altering vertical dimensions.
The wind load requirements of this standard (0,1 kN/m ).
Consider the fact that mobile access towers are generally intended for shorter duration tasks and may
be re-located or quickly dismantled. Attention is drawn to 3.1, Note 2 and to the requirements of
EN 1298 regarding information relating to wind conditions.
Mobile access and working towers are not anchor points for personal fall arrest equipment unless they
are specifically designed in accordance with relevant European standards by the manufacturer for that
purpose.
1 Scope
This document applies to the design of mobile access and working towers made of prefabricated
elements with dimensions which are fixed by the design and with a height up to 12 m (indoors) and up
to 8 m (outdoors). This document applies to mobile access and working towers used as temporary work
equipment.
This document:
— gives guidelines for the choice of the main dimensions and stabilizing methods,
— gives safety and performance requirements, and
— gives information on complete towers.
This product standard does not apply to scaffolds according to EN 12810-1 and EN 12811-1.
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 131-2, Ladders — Part 2: Requirements, testing, marking
EN 1298, Mobile access and working towers — Rules and guidelines for the preparation of an instruction
manual
1)
EN 1991-1-4:2005, Eurocode 1: Actions on structures — Part 1-4: General actions - Wind actions
EN 1993-1-1, Eurocode 3: Design of steel structures — Part 1-1: General rules and rules for buildings
EN 1995-1-1, Eurocode 5: Design of timber structures — Part 1-1: General — Common rules and rules for
buildings
2)
EN 1999-1-1 , Eurocode 9: Design of aluminium structures — Part 1-1: General structural rules
EN 12810-2:2003, Façade scaffolds made of prefabricated components — Part 2: Particular methods of
structural design
EN 12811-1, Temporary works equipment — Part 1: Scaffolds — Performance requirements and general
design
EN 12811-2, Temporary works equipment — Part 2: Information on materials
EN 12811-3, Temporary works equipment — Part 3: Load testing
EN ISO 2081, Metallic and other inorganic coatings — Electroplated coatings of zinc with supplementary
treatments on iron or steel (ISO 2081)

1) This document is impacted by the amendment EN 1991-1-4:2005/A1:2010.
2) This document is impacted by the amendments EN 1999-1-1:2007/A1:2009 and EN 1999-1-1:2007/A1:2013.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
mobile access and working towers
temporary free-standing structures consisting of prefabricated elements, having dimensions fixed by
the design and four legs with castors, providing one or more platforms
Note 1 to entry: Mobile access and working towers can have outriggers or stabilizers. They can be stabilized by
supports on the ground or wall struts against a stable structures or ballast.
Note 2 to entry: Mobile access and working towers have castor wheels. Mobile access and working towers can
be removed immediately, in case of arising wind greater than equivalent dynamic pressure 0,1 kN/m or at the
end of the work shift.
3.2
height (h)
distance from the ground to the upper surface of the uppermost platform
3.3
castor wheel
swivelling wheel secured to the base of a mobile access and working tower to enable the tower to be
moved
3.4
adjustable leg
component incorporated into the structure of a mobile access and working tower at its base used for
the purpose of levelling the structure when situated on uneven or sloping ground
3.5
platform unit
prefabricated unit which forms the platform or part of the platform, that supports a load on its own and
might form a structural part of the mobile access and working tower
3.6
bracing member
means used to stiffen the structure
3.7
outrigger
component that increases the effective base dimensions of a tower, with provision for the attachment of
a castor
3.8
stabilizer
component that increases the effective base dimensions of a tower, without provisions for the
attachment of a castor
3.9
ballast
weights placed at the base of the tower to increase its resistance to overturning
3.10
wall strut
means for providing compressive restraint to prevent a tower overturning
Note 1 to entry: It is normally a horizontal tubular member, one end of which is connected to the tower, while
the other end rests against a wall or other structure.
3.11
stairway
means of access intended for persons carrying tools or materials
3.12
stairladder
means of access intended for person's not carrying tools or materials
3.13
inclined ladder
means of access intended for persons not carrying tools or materials with an inclination from 60° to 75°
3.14
vertical ladder
means of access intended for persons not carrying tools or materials with an inclination of 90°
3.15
platform
one or more platform units placed side by side at the same level
3.16
platform length (l)
greater of the two plane dimensions at the platform level
Note 1 to entry: See Figure 1.
3.17
platform width (w)
lesser of the two plane dimensions at the platform level
Note 1 to entry: See Figure 1.

Figure 1 — Width and length of a platform
3.18
indoors
place where the tower will not be exposed to wind loads
3.19
outdoors
place where the tower might be exposed to wind loads
3.20
side protection
components forming a barrier to protect people from the risk of falling and to retain materials
3.21
working platform
platform in a mobile access and working tower from where the work will be carried out
3.22
intermediate platform
platform in a mobile access and working tower that is not a working platform
3.23
positive locking device
mechanical locking device not relying on friction which prevents unintentional disconnection
EXAMPLE A pin, bolt or protrusion.
4 Classification
4.1 Load classes
The classes of uniformly distributed load are given in Table 1.
Table 1 — Classes of uniformly distributed load
Uniformly distributed load q
Load class
kN/m
2 1,50
3 2,00
4.2 Access classes
Four options for access to the platform are described in 7.6.
4.3 Height classes
Two options for minimum clear height between platforms are described in 7.2.
5 Designation
The following data are required for the designation of all prefabricated mobile access and working
towers:
a) class of uniformly distributed load (see 4.1);
b) maximum height outdoors/indoors;
c) access classes (see 4.2);
d) clear height classes (see 4.3).
Example
6 Materials
Materials shall fulfil the requirements given in European standards, where design data are provided. If
European standards do not exist, ISO standards can be applied.
Materials shall be sufficiently robust and durable to withstand normal working conditions.
Additional requirements for some materials are given in EN 12811-2.
When materials are used, whose properties in relation to the intended application (e.g. temperature,
ageing, UV-degradation) are not given in any available standard an adequate assessment is required.
Steel shall be protected by one of the methods given in EN 12811-2, or zinc plated to the level required
for the design service environment stated in EN ISO 2081.
7 General requirements
7.1 General
A mobile access and working tower shall only consist of a single-bay structure.
The mobile access and working tower shall be designed such that it can be assembled, altered and
dismantled without the need for personal fall protection equipment.
Only one platform shall be a working platform at one time.
The mobile access and working tower shall be designed in such a way that the uppermost platform is a
working platform and lower platforms are intermediate platforms.
NOTE An intermediate platform can be changed to be the working platform if it is equipped with side
protection, including toe boards.
The vertical distance between platforms shall be no greater than 2,25 m.
The vertical distance between the ground and the first platform shall be no greater than 3,40 m.
However, if a platform is placed ≤ 0,6 m from the ground, it is allowed to have a vertical distance no
greater than 3,40 m between that platform and the next platform. See Figure 2.
If the mobile access and working tower cannot be entered from the inside of the structure, the
requirements of 7.11 shall apply.

Key
x ≤ 0,6 m
y ≤ 3,40 m
z ≤ 2,25 m
1 first platform
2 second platform
NOTE Stabilizers are omitted from this figure for clarity.
Figure 2 — Maximum distance between platforms
7.2 Dimensions
The minimum width, w, of the platform shall be 0,60 m and the minimum length, l, shall be 1,00 m. See
Figure 1.
The minimum clear width between the toe boards shall be 0,5 m.
The minimum clear height between platforms H shall be in accordance with Table 2.
Table 2 — Clear height classes
Clear height class Minimum clear height H in m
H1 1,85
H2 1,90
7.3 Openings within platforms
7.3.1 Access openings
Access openings in platforms through which the user will climb shall have a minimum clear opening of
0,40 m wide × 0,60 m long.
Access openings in platforms shall be provided with a means to prevent falling through. The trapdoor
shall be fastenable in the closed position.
7.3.2 Apertures
Apertures in platforms or between platform units shall not exceed 25 mm in width. This does not apply
to apertures like hand holes in hatches.
7.4 Side protection
7.4.1 General
Dimensions for side protection shall be in accordance with Figure 3.
Dimensions in millimetres
Key
h distance between uppermost surface of the platform and uppermost surface of the principal guardrail
GR
r corner radius of side protection consisting of a frame to be constant (see 7.4.3)
const
Figure 3 — Dimensions for side protection
Side protection is composed of a principal guardrail, intermediate side protection and a toe board. The
principal guardrail, intermediate side protection, and toe-board may be combined.
Side protection components shall be incapable of removal except by direct intentional action.
It shall be possible to erect protection at platform edges comprising:
a) both a principal guardrail and intermediate side protection;
b) toe-board.
3)
Toe boards may be omitted on intermediate platforms.
7.4.2 Principal guardrail
The principal guardrail shall be fixed so that its uppermost surface is a minimum of 1 000 mm above the
uppermost surface of the platform it is protecting, measured vertically (dimension h in Figure 3). A
GR
minus tolerance of 50 mm is acceptable.
7.4.3 Intermediate side protection
Intermediate side protection shall be fixed between the principal guardrail and the toe-board.
Intermediate side protection may consist of:
— one or more intermediate guardrails, or
— a frame, or
3) See A-deviations in Annex B.
— a frame of which the principal guardrail forms the top edge, or a fencing structure.
Openings in the side protection shall be so dimensioned so that a sphere with a diameter of more than
470 mm will not pass through them.
7.4.4 Toe-board
It shall be possible to fix a solid toe-board such that its top edge is at least 150 mm above the adjacent
platform level. Apertures in toe boards shall not exceed 25 mm in width. This does not apply to
apertures like hand holes.
7.5 Castor wheels
7.5.1 General
Castor wheels shall be fixed to the tower in such a way that they cannot be unintentionally detached.
The castor wheel shall not detach from the frame due to the action of its self-weight.
7.5.2 Brakes
All castors shall have wheel brakes. They shall have swivel brakes if the wheels are eccentric when
locked.
The brake mechanism shall be designed in such a way that it can only be unlocked by a deliberate
action. The brake mechanism shall effectively prevent any rotation of the wheel when a horizontal force
of 0,30 kN is applied through the vertical swivel axis of the castor as close as possible above the castor
housing and in the rolling direction of the castor. The full value of the specified service load per castor
wheel is to be applied when testing the castor brakes. A minimum of five control tests shall be carried
out.
7.5.3 Test loads
The test shall be carried out on the complete castor wheel.
The vertical service load per wheel given by the manufacturer of the mobile access and working tower
shall be verified by a minimum of five tests.
The test load shall be three times the service load per castor wheel derived from the most unfavourable
load combination from Table 3.
When the brakes are locked, an initial vertical load of 0,50 kN shall be applied. The plate of the fork shall
be taken as the origin for measurements of vertical displacement, d , and the residual deformation, d .
c r
The load shall be increased to the maximum test load, maintained for one minute and the vertical
deformation, d , shall be measured. The load shall be returned to 0,50 kN. After 30 min, the residual
c
deformation, d , shall be measured.
r
The test shall meet both of the following requirements:
— residual deformation, d , after 30 min shall not be more than 3,00 mm;
r
— total deformation, d , shall not be more than 15 mm.
c
The service load is verified if all five tests meet the test requirements.
7.5.4 Wheels
Wheels shall be of puncture less type.
7.6 Access to platforms
7.6.1 Access types
The access type is classified by a letter A, B, C or D as follows:
— Access type A: Stairway;
— Access type B: Stairladder;
— Access type C: Inclined ladder;
— Access type D: Vertical ladder.
Where a range of access types is provided, a combined classification is used.
EXAMPLES
Type AXCX means that stairways and inclined ladders can be provided.
Type ABCD means that all four types of access can be provided.
NOTE The X in the designation means that those types of access are not provided.
7.6.2 General requirements
Access to the platforms ≥ 2 m height in an assembled tower shall be within the main structural supports
using one of the access methods specified in 7.6.1 and shall:
— be secured against unintentional loosening;
— not rest on the ground;
— have a distance from the ground to the first step or rung of 400 mm maximum taking into account
adjustable legs. If the first step is a platform, 600 mm is allowable;
— have steps/rungs with constant spacing and a slip resistant surface.
7.6.3 Additional requirements
7.6.3.1 Stairway and stairladder
The outside of stair flights shall be provided with a handrail which runs approximately parallel to the
stairs. Where a flight of stairs is provided in a continuous dog-leg style, a handrail shall also be provided
on the inside. When flights of stairs are interrupted by platforms at ≤ 2,25 m intervals, the inside
handrail may be omitted.
Flights of stairs in a continuous dog-leg style shall have landings. Each of these stairs shall have a
minimum of one landing and this shall have a minimum length of 300 mm.
The minimum clear height for access measured between the steps and the supporting structure of the
stairway or stairladder above shall not be less than 1,75 m.
7.6.3.2 Access type A - stairway (see Figure 4)
Stairways shall conform with the following geometric requirements:
Inclination α 35° ≤ α ≤ 55°;
Vertical step rise t1 190 mm ≤ t1 ≤ 250 mm;
Minimum step depth d d = 125 mm;
Minimum clear width w w = 400 mm;
clear clear
Horizontal gap between steps g 0 ≤ g ≤ 50 mm.
Stairways shall be designed in accordance with 8.3.3.

Figure 4 — Dimensions of stairway
7.6.3.3 Access type B - stairladder (see Figure 5)
Stairladders shall conform with the following geometric requirements:
Inclination α 35° ≤ α ≤ 55°;
Vertical step rise t 150 mm ≤ t ≤ 250 mm;
1 1
Minimum step depth d d = 80 mm;
Minimum clear width w w = 280 mm;
clear clear
Horizontal gap between steps g 0 ≤ g ≤ 160 mm.
Stairladders shall be designed in accordance with 8.3.3.

Figure 5 — Dimensions of stairladder
7.6.3.4 Access type C - inclined ladder (see Figure 6)
Inclined ladders shall conform with the following geometric requirements:
Inclination α 60° ≤ α ≤ 75°;
Step spacing t2 230 mm ≤ t2 ≤ 300 mm;
Step depth d d > 80 mm;
Rung spacing t 230 mm ≤ t ≤ 300 mm;
2 2
Rung diameter d 20 mm ≤ d ≤ 80 mm;
Minimum clear width w w = 280 mm.
clear clear
Inclined ladders shall be designed in accordance with 8.3.4.

Figure 6 — Dimensions of inclined ladder
7.6.3.5 Access type D -vertical ladder (see Figure 7)
Vertical ladders shall conform with the following geometric requirements:
From the front edge of the step or from the centre of the rung to any obstacle behind the
stairway/ladder, there shall be a horizontal distance of s = 150 mm minimum (see Figure 7).
Rung spacing t 230 mm ≤ t ≤ 300 mm;
2 2
Rung depth or diameter d 20 mm ≤ d ≤ 51 mm;
Minimum clear width w w = 280 mm.
clear clear
Vertical ladders shall be designed in accordance with 8.3.5.
a) Separate ladder b) Integral ladder                       c) w
clear
Figure 7 — Dimensions of vertical ladder
7.7 Means for stabilizing
7.7.1 Stabilizers and outriggers
The stabilizers and outriggers of a tower shall be designed as components of the main structure and
shall provide means of adjustment to ensure contact with the ground.
The method of fixing the stabilizer or outrigger to the tower shall have adequate strength and shall be
such that the reaction loads in the stabilizer or outrigger are transferred to the tower without slip,
rotation, or other movement of the stabilizer or outrigger.
7.7.2 Ballast
If ballast is necessary, it shall be securely positioned to prevent unintentional movement or removal.
Ballast shall be made of rigid materials such as steel or concrete. Alternatively, liquids or granular
materials may be used if they are in containers supplied by the manufacturer.
The containers shall have the following characteristics:
— they shall be closable and lockable to prevent escape of the filling material;
— they shall be impact resistant to prevent loss of the filling material;
— their filling level shall be clearly visible;
— the filling material shall be specified by the manufacturer.
7.8 Connections
7.8.1 General
Each connection device shall be effective, easy to monitor and the components shall be easy to
assemble. The securing of components forming part of the structure of the mobile access tower and
working tower and side protection components shall make them incapable of removal except by direct
intentional action.
7.8.2 Vertical spigot and socket connection
When assembled, the horizontal movement (slack or play) between upper and lower components shall
not exceed 4 mm or a movement away from the centre line of 2 mm.
In all cases, it shall not be possible to disconnect an upper component laterally until the upper
component has been lifted more than 80 mm.
When the spigot and socket connection acts over a distance less than 150 mm, the connection shall be
provided with a positive locking device, such as a cross pin, to prevent the upper component from being
lifted unintentionally and provide additional structural stiffness.
The positive locking device shall be designed in such a way that its positive action can be monitored
visually.
7.8.3 Other vertical connections
There shall be equivalent provisions related to 7.8.2 to limit the risk of accidental disconnections and
provide structural stiffness.
7.9 Working and access platform units
Components of platforms shall be durable and shall have a slip-resistant surface. Platform units shall be
secured at both ends so that turning or removal by wind is not possible.
7.10 Erection and dismantling
The tower shall remain stable and resist all loads imposed on the components during erection and
dismantling.
7.11 Requirements for mobile access towers less than 2 m working platform height
7.11.1 Requirements for access
Access to the platform in an assembled tower shall:
— be an integral component or components of the tower;
— be secured against unintentional loosening;
— have a distance from the ground to the first step or rung of 400 mm maximum taking into account
adjustable legs;
— have steps/rungs with constant spacing and a slip resistant surface;
— shall comply with the requirements of 7.6.
There is no requirement for access if the working platform height is ≤ 600 mm.
Access to working platforms in an assembled tower may be from the outside of the structure.
The structure may be provided with access openings in the side protection provided that:
— it shall be possible to close access openings in the side protection after access or egress;
— access openings in the side protection shall be provided with a means to prevent unintentional
opening;
— access openings in the side protection shall have a minimum clear width ≥ 400 mm:
— the access to the platform shall be aligned with access openings in the side protection;
— access openings in the side protection shall be designed in such a way that only one hand is
required to opening.
NOTE Attention is drawn to national regulation regarding work at height when considering side protection
for mobile access towers less than 2 m working platform height.
7.11.2 Requirements for positional stability when accessing from outside
7.11.2.1 General
This load case shall only be applied when a mobile access tower has an access provided from outside
the structural supports, in accordance with 7.11.1.
7.11.2.2 Safety factor
The safety factor against overturning shall be S ≥ 1,5.
7.11.2.3 Vertical loads
— Self-weight;
— a vertical load of either:
— for access types A, B and C; 0,75 kN applied to the first step or rung, or
— for access types D; 0,75 kN applied 0,5 m outside of the vertical plane of access.
8 Requirements for structural design
8.1 General
A tower structure shall be able to resist the combination of loads, taking from one line from each of the
five groups given in Table 3, in their worst combinations.
All loads are taken to be static loads.
Eccentricities of castor wheels, in their most unfavourable position, shall be taken into account.
Adjustable legs shall be extended to their maximum extension.
Platforms shall be assessed with respect to self-weight and the most unfavourable design load
according to Table 4.
8.2 Characteristic actions on the complete structure including its parts
8.2.1 Verticals loads
8.2.1.1 Tower nominal self-weight as given by the manufacturer
The self-weight of the tower including all parts and ballast (if applicable) shall be taken into account.
8.2.1.2 Uniformly distributed load on the topmost platform
— Load class 2: 1,5 kN/m ;
— Load class 3: 2,0 kN/m .
8.2.1.3 Load resulting from an inclination of 1 %
Vertical loads to be taken into consideration are:
— nominal self-weight as given (see 8.2.1.1);
— vertical service loads as given (see 8.2.1.2).
8.2.1.4 Minimum vertical service load on the structure, equally distributed on 4 legs
P = 5,0 kN;
NOTE P can be larger than 5,0 kN in accordance with the uniformly distributed loads as given in Table 3.
8.2.2 Horizontal loads
8.2.2.1 Horizontal service load on the topmost platform
On the level of the platforms with length l:
— l ≤ 4,0 m : 0,3 kN;
— l > 4,0 m : 2 × 0,3 kN.
NOTE 0,3 kN is taken from EN 12811-1.
8.2.2.2 Horizontal loads on all components to simulate wind
0,1 kN/m multiplied by the appropriate aerodynamic force coefficients c .
f
Aerodynamic force coefficients, c , appropriate for some cross sections of components of mobile access
f
towers, are given in EN 1991-1-4.
The value for the aerodynamic force coefficients c may be taken as 1,3 for all projected areas including
f
platforms and toe boards.
NOTE
0,1 kN/m relates to the peak velocity pressure, q , according to EN 1991-1-4:2005, 4.5.
p
0,1 kN/m refers to a wind velocity of vp = 45,5 km/h = 12,7 m/s.
The wind affected area shall include the required side protection components at the working level and
the intermediate levels.
Shelter effects for more than one component being upwind may be taken into consideration by the
application of EN 1991-1-4:2005, 7.9 and 7.11, as appropriate.
Alternatively, shelter effects may be taken into consideration, according to Annex C.
8.3 Characteristic actions on parts of the structure
8.3.1 Loads on platform units
Platform units and the supporting structure shall be designed for concentrated loads and uniformly
distributed loads in accordance with Table 4.
The requirements for concentrated loads and uniformly distributed loads shall be fulfilled separately.
8.3.2 Load on side protection
8.3.2.1 Downward load
Any principal guardrail or intermediate guardrail, regardless of its method of support, shall be able to
resist a point load of 1,25 kN. This also applies to any other side protection component, such as a
fencing structure, which has a potential foothold of 50 mm wide or greater.
This load shall be considered as an accidental load and applied in the most unfavourable position in a
downward direction within a sector of ± 10° from the vertical.
8.3.2.2 Horizontal load
All components of the side protection, except toe-boards, shall be able to resist a horizontal load of
0,3 kN in each case in the most unfavourable position. This load may be distributed over an area of
300 mm × 300 mm, e.g. when applied to the grid of a fencing structure. For toe-boards, the horizontal
load is 0,15 kN.
Table 3 — Service loads on the whole structure
Group Line Kind of load Value of Subclause
load
1 Self-weight including ballast if as given 8.2.1.1
applicable
2 Vertical service load on the
topmost platform
2.1 Uniformly distributed load 8.2.1.2
2.1.1 for load class 2 2
1,5 kN/m
2.1.2 for load class 3 2
2,0 kN/m
2.2 minimum service load on the 5,0 kN/4
structure legs
3 Horizontal service load on the 8.2.2.1
topmost platform
a
3.1 l ≤ 4,0 m 0,3 kN
a
3.2 l > 4,0 m 2 × 0,3 kN
4 Horizontal loads to simulate 8.2.2.2
wind
5 Loads resulting from an 8.2.1.3
inclined position of 1 %
a
l = length of the platform
Table 4 — Service loads on parts of the structure
Line Element Type of load Value of Subclause
loads
1 platform
Uniformly distributed  8.2.1.2
1.1
on the whole area
Load class 2 2
1.1.1
1,5 kN/m
Load class 3 2
1.1.2
2,0 kN/m
Concentrated on an 1,5 kN 8.3.1
area of
500 mm × 500 mm in
the most unfavourable
position on the
1.2
platform
If the width of the
platform unit is less
than 500 mm, the load
shall not be reduced.
Concentrated on an 1,0 kN 8.3.1
area of
200 mm × 200 mm in
1.3
the most unfavourable
position on the
platform
2 guardrail
A downward point load 1,25 kN 8.3.2.1
on the guardrail in the
2.1
most unfavourable
position
A horizontal point load 0,3 kN 8.3.2.2
on the guardrail in the
2.2
most unfavourable
position
Toe board A horizontal point load 0,15 kN 8.3.2.2
on the toe board in the
most unfavourable
position
8.3.3 Load on stairways and stairladders
Each tread and landing shall be designed to support the more unfavourable of either:
a) a single load of 1,5 kN in the most unfavourable position, assumed to be uniformly distributed over
an area of 200 mm × 200 mm or over the actual width if it is less than 200 mm, or
b) a uniformly distributed load of 1,0 kN/m .
The structures of stairways and stair ladders shall be capable of supporting a uniformly distributed load
of 1,0 kN/m on all treads and landings.
8.3.4 Load on inclined ladders
Inclined ladders shall be designed in accordance with the test for torsion and vertical load on rungs in
EN 131-2.
8.3.5 Load on Vertical ladder
Vertical ladders shall be verified either by;
— structural analysis for the following characteristic vertical load, always acting in the most adverse
= 1,5 kN acting on 200 mm, or
position of F1,k
— in accordance with the test for torsion and vertical load on rungs in EN 131-2.
8.4 Deflections
8.4.1 Elastic deflection of platform components
When subjected to the concentrated loads specified in Table 4, line 1.2, the elastic deflection of any
platform component shall not exceed 0,01 of the span of that platform component.
In addition, in the case of platform components with spans of 2,5 m or greater, when the appropriate
concentrated load is applied, the maximum difference in levels between adjacent loaded and unloaded
platform components shall not exceed 25 mm.
8.4.2 Elastic deflection of side protection
When subjected to the load specified in Table 4, line 2.2, the maximum deflection of any principle or
intermediate guardrail, regardless of its span, shall not exceed 35 mm. When subjected to the load
specified in Table 4; line 3, the maximum deflection of any toe-board, regardless of its span shall not
exceed 35 mm. These are measured with reference to the supports at the points where they are
connected.
9 Structural design
9.1 Basic design principle
9.1.1 Introduction
Mobile access and working towers shall be designed for load bearing capacity, serviceability and
resistance to overturning. Unless otherwise stated in this clause, the Eurocodes for structural design
shall be applied.
The strength of joints and connections (e.g. welded joints, compressed connections, hollow type rivet
connections) shall be verified.
Concepts relate to the limit state method.
Full scale or detail testing may be undertaken in accordance with EN 12811-3 to suppl
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