SIST EN 792-6:2000+A1:2008
(Main)Hand-held non-electric power tools - Safety requirements - Part 6: Assembly power tools for threaded fasteners
Hand-held non-electric power tools - Safety requirements - Part 6: Assembly power tools for threaded fasteners
The standard EN 792 applies to hand-held non-electric power tools driven by rotary or linear motors, powered by compressed air, hydraulic fluid and intended to be used by one operator and supported by:
- the operator's hand or hands
- a suspension, e.g. a balancer.
This part, EN 792-6, applies to hand-held, non-electric, power tools for tightening or installing of threaded fasteners. This part lists the significant hazards caused by such power tools and specifies safety requirements valid for different aspects of safety during their foreseeable lifetime.
Power tools covered by this part of the standard:
- air-hydraulic impulse wrenches,
- impact wrenches,
- fastener installation tools,
- nut runners,
- open-ended spanners,
- ratchet wrenches,
- screwdrivers.
Special requirements and modifications on a hand-held power tool for the purpose of mounting it in a fixture are not covered by this part.
NOTE At the date of publication no assembly power tools for threaded fasteners driven by internal combustion engines are known.
Handgehaltene nicht-elektrisch betriebene Maschinen - Sicherheitsanforderungen - Teil 6: Maschinen für Schraubverbindungen
Die Norm EN 792 gilt für handgehaltene nicht-elektrisch betriebene Maschinen, die durch Motore mit
drehender oder linearer Bewegung angetrieben werden, wobei die Energie aus Druckluft oder über Hydraulikflüssigkeit
bezogen werden kann. Die Maschinen sind dazu bestimmt, durch eine Person verwendet und
- mit einer oder beiden Händen gehalten;
- in einer Halterung, z. B. Aufhängevorrichtung, aufgenommen
zu werden.
Dieser Teil, EN 792-6, gilt für handgehaltene nicht-elektrisch betriebene Maschinen zum Anziehen oder
Einsetzen von Befestigungselementen mit Gewinde. Dieser Teil listet die wesentlichen, von diesen Maschinen
ausgehenden Gefährdungen auf und beschreibt die besonderen Sicherheitsanforderungen für die
verschiedenen Sicherheitsaspekte während ihrer vorhersehbaren Lebensdauer.
Handgehaltene Maschinen, die in diesem Teil der Norm behandelt werden:
- Luft-hydraulische Schlagschrauber;
- Schlagschrauber;
- Maschinen zur Installation von Befestigungselementen;
- Mutternschrauber;
- Maulschlüsselschrauber;
- Ratschenschrauber;
- Schraubendreher.
Besondere Anforderungen und Änderungen an handgehaltene Maschinen zum Zwecke des Spannens in
einer Halterung, werden in diesem Teil nicht behandelt.
ANMERKUNG Zum Zeitpunkt der Veröffentlichung dieser Norm sind keine Maschinen für Schraubverbindungen
bekannt, die durch einen Verbrennungsmotor angetrieben werden.
Machines portatives à moteur non électrique - Prescriptions de sécurité - Partie 6: Machines portatives d'assemblage pour éléments de fixation filetés
La norme européenne EN 792 s'applique aux machines portatives non électriques entraînées par des moteurs rotatifs ou linéaires, alimentés par air comprimé, fluide hydraulique et prévues pour être utilisées par un seul opérateur et portée par :
la ou les main(s) de l'opérateur,
en suspension, par exemple à l'aide d'un équilibreur.
Cette partie, EN 792-6, s'applique aux machines portatives non électriques utilisées pour le serrage ou la mise en place d'éléments de fixation filetés. Elle énumère les risques significatifs provoqués par de telles machines portatives et spécifie les prescriptions de sécurité relatives aux différents aspects de sécurité pouvant être rencontrés pendant leur durée de vie.
La présente norme couvre les types de machines portatives suivantes :
clés à choc hydropneumatiques ;
clés à choc ;
machines pour mise en place d'éléments de fixation ;
serreuses ;
serreuse à fourche ;
clés à rochet ;
visseuses.
Les prescriptions particulières et les modifications sur les machines portatives dans le but de les monter sur un bati ne sont pas couvertes par la présente partie.
NOTE À la date de publication, il n'y a pas de machine portative d'assemblage pour éléments de fixation filetés mue par un moteur à combustion interne connue.
Neelektrična ročna orodja - Varnostne zahteve - 6. del: Električna orodja za pritrjevanje z navojem
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 792-6:2000+A1:2008
01-november-2008
1HHOHNWULþQDURþQDRURGMD9DUQRVWQH]DKWHYHGHO (OHNWULþQDRURGMD]D
SULWUMHYDQMH]QDYRMHP
Hand-held non-electric power tools - Safety requirements - Part 6: Assembly power tools
for threaded fasteners
Handgehaltene nicht-elektrisch betriebene Maschinen - Sicherheitsanforderungen - Teil
6: Maschinen für Schraubverbindungen
Machines portatives à moteur non électrique - Prescriptions de sécurité - Partie 6:
Machines portatives d'assemblage pour éléments de fixation filetés
Ta slovenski standard je istoveten z: EN 792-6:2000+A1:2008
ICS:
25.140.10 3QHYPDWLþQDRURGMD Pneumatic tools
SIST EN 792-6:2000+A1:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 792-6:2000+A1:2008
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SIST EN 792-6:2000+A1:2008
EUROPEAN STANDARD
EN 792-6:2000+A1
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2008
ICS 25.140.10; 25.140.99 Supersedes EN 792-6:2000
English Version
Hand-held non-electric power tools - Safety requirements - Part
6: Assembly power tools for threaded fasteners
Machines portatives à moteur non électrique - Prescriptions Handgehaltene nicht-elektrisch betriebene Maschinen -
de sécurité - Partie 6: Machines portatives d'assemblage Sicherheitsanforderungen - Teil 6: Maschinen für
pour éléments de fixation filetés Schraubverbindungen
This European Standard was approved by CEN on 26 May 2000 and includes Amendment 1 approved by CEN on 23 July 2008.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 792-6:2000+A1:2008: E
worldwide for CEN national Members.
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EN 792-6:2000+A1:2008 (E)
Contents Page
Foreword.3
Introduction .4
1 Scope .4
2 Normative references .5
3 Terms and definitions .6
3.1 General terms and definitions.6
3.2 Terms and definitions related to assembly power tools for threaded fasteners .7
4 List of hazards.8
5 Safety requirements and measures.10
5.1 Mechanical safety .10
5.2 Thermal safety.10
5.3 Noise .10
5.4 Vibration .11
5.5 Materials and substances processed, used or exhausted.11
5.6 Ergonomics .11
5.7 Safety related measures and means.13
6 Information for use .14
6.1 Marking, signs and written warnings.14
6.2 Instruction for use .14
7 Verification .17
7.1 Noise .17
7.2 Vibration .17
7.3 Unintentional start .17
7.4 Structure of verification .18
Annex A (informative) Examples of assembly power tools for threaded fasteners covered by this
part .19
Annex B (informative) Symbols for labels and signs .21
Annex C (normative) Safety requirements related to the internal combustion engines .22
Annex ZA (informative) !Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC".25
Annex ZB (informative) !Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC".26
Bibliography .27
2
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EN 792-6:2000+A1:2008 (E)
Foreword
This document (EN 792-6:2000+A1:2008) has been prepared by Technical Committee CEN/TC 255 "Hand-
held, non-electric power tools - Safety", the secretariat of which is held by SIS.
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 March 2009 and conflicting national standards shall be withdrawn at
the latest by December 2009.
This European Standard 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 Annexes ZA and ZB, which are integral parts of this
document."
This document includes Amendment 1, approved by CEN on 2008-07-23.
This document supersedes EN 792-6:2000.
The start and finish of text introduced or altered by amendment is indicated in the text by tags ! ".
The standard has been created in close co-operation with CENELEC/TC 61F with the aim of achieving
requirements for mechanical safety in the EN 50144 series, which are similar for hand-held electric and non-
electric power tools.
The annexes to this part of the standard are:
Annex A (informative) Examples of power tools covered by this part
Annex B (informative) Labels, signs and tags
!Annexes ZA and ZB" (informative) Clauses of this European Standard addressing essential
requirements or other provisions of EU Directives.
This standard also contains a Bibliography.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and United Kingdom.
3
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EN 792-6:2000+A1:2008 (E)
Introduction
This European standard is a type C standard as stated in EN 1070.
The machinery concerned and the extent to which hazards, hazardous situations and events are covered are
indicated in the scope of this standard.
When provisions of this type C standard are different from those which are stated in type A or B standards, the
provisions of this type C standard take precedence over the provisions of other standards, for machines that
have been designed and built according to the provisions of this type C standard.
The European Standard, EN 792, consists of a number of independent parts for individual types of hand-held
non-electric power tools.
Other EN standards deal with safety rules for hand-held power tools used in e. g. the following fields:
agriculture and forestry such as chain saws, hedge-trimmers, brush cutters, grass trimmers;
construction and building such as cutting-off power tools, concrete vibrators;
food industry, such as fowl secateurs, sheep shears.
Endeavours have been made to achieve co-ordination with the relevant Technical Committees so that the
safety requirements are compatible.
This standard is divided in the following parts:
Part 1 - Assembly power tools for non-threaded mechanical fasteners (former part 14)
Part 2 - Cutting-off and crimping power tools (former part 15)
Part 3 - Drills and tappers
Part 4 - Non rotary percussive power tools
Part 5 - Rotary, percussive power drills
Part 6 - Assembly power tools for threaded fasteners
Part 7 - Grinders
Part 8 - Sanders and polishers
Part 9 - Die grinders
Part 10 - Compression power tools
Part 11 - Nibblers and shears
Part 12 - Small circular, small oscillating and reciprocating saws
Part 13 - Fastener driving tools
Certain parts of EN 792 cover hand-held non-electric power tools, driven by internal combustion engines
powered by gaseous or liquid fuel. In these parts, the safety aspects relating to internal combustion engines
are found in a normative annex.
The parts are type C standards and refer to pertinent European Standards of type A and B where such
standards are applicable.
1 Scope
The standard EN 792 applies to hand-held non-electric power tools driven by rotary or linear motors, powered
by compressed air, hydraulic fluid and intended to be used by one operator and supported by:
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EN 792-6:2000+A1:2008 (E)
the operator's hand or hands
a suspension, e.g. a balancer.
This part, EN 792-6, applies to hand-held, non-electric, power tools for tightening or installing of threaded
fasteners. This part lists the significant hazards caused by such power tools and specifies safety requirements
valid for different aspects of safety during their foreseeable lifetime.
Power tools covered by this part of the standard:
air-hydraulic impulse wrenches,
impact wrenches,
fastener installation tools,
nut runners,
open-ended spanners,
ratchet wrenches,
screwdrivers.
Special requirements and modifications on a hand-held power tool for the purpose of mounting it in a fixture
are not covered by this part.
NOTE At the date of publication no assembly power tools for threaded fasteners driven by internal combustion
engines are known.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications.
These normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of the publications referred to
in this European Standard are valid only when they are incorporated in this standard by amendment or
revision. For undated references the latest edition of the publication referred to, applies (including
amendments).
EN 292-1:1991, Safety of machinery - Basic concepts, general principles for design – Part 1: Basic
terminology, methodology
EN 292-2:1991, Safety of machinery - Basic concepts, general principles for design – Part 2: Technical
principles and specifications
EN 563, Safety of machinery - Temperatures of touchable surfaces - Ergonomics data to establish
temperature limit values for hot surfaces
EN 614-1, Safety of machinery - Ergonomic design principles – Part 1: Terminology and general principles
EN 1070, Safety of machinery - Terminology
EN 12096, Mechanical vibration - Declaration and verification of vibration emission values
EN ISO 4871, Acoustics - Declaration and verification of noise emission values of machinery and equipment
(ISO 4871:1996)
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!EN ISO 15744:2008, Hand-held non-electric power tools – Noise measurement code – Engineering
method (grade 2) (ISO 15744:2002)"
EN 28662-1, Hand-held portable power tools - Measurement of vibrations at the handle – Part 1: General (ISO
8662-1:1988)
EN ISO 8662-7, Hand-held portable power tools - Measurement of vibrations at the handle – Part 7:
Wrenches, screwdrivers and nut runners with impact, impulse or ratchet action (ISO 8662-7:1997)
ISO 3857-1, Compressors, pneumatic tools and machines - Vocabulary – Part 1: General
ISO 5391, Pneumatic tools and machines - Vocabulary
ISO 9158, Road vehicles - Nozzles spouts for unleaded fuel
ISO 9159, Road vehicles - Nozzles spouts for leaded gasoline and diesel fuel
3 Terms and definitions
For the purposes of this part of the standard, the following terms and definitions apply:
3.1 General terms and definitions
3.1.1
hand-held power tool
machine driven by rotary or linear motors powered by compressed air, hydraulic fluid, gaseous or liquid fuel,
electricity or stored energy (e.g. by a spring) to do mechanical work and so designed that the motor and the
mechanism form an assembly that can easily be brought to its place of operation. The hand-held power tool is
operated by one or two hands
NOTE Hand-held power tools driven by compressed air or gas are called pneumatic tools. Hand-held power tools
driven by hydraulic liquid are called hydraulic tools.
3.1.2
rotary power tool
hand-held power tool the machine spindle of which rotates
3.1.3
inserted tool
tool inserted in the hand-held power tool to perform the intended work
3.1.4
service tool
tool intended for performing maintenance or service on the hand-held power tool
3.1.5
control device
device to start and stop the hand-held power tool or to change the direction of the rotation or to control the
functional characteristics such as speed and power
3.1.6
maximum operating pressure
maximum pressure that a hand-held power tool may be operated at, as specified by the manufacturer
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3.2 Terms and definitions related to assembly power tools for threaded fasteners
3.2.1
screwdriver
rotary power tool, with a reversible or non-reversible spindle fitted with a screwdriver bit, for the purpose of
tightening or loosening threaded fasteners, usually screws.
Screw drivers can be straight, pistol-grip or angle types, and may or may not have a clutch; these terms are
defined by ISO 5391
3.2.2
nutrunner
rotary power tool, with a reversible or non-reversible spindle fitted with a drive adapter for the purpose of
tightening or loosening nuts and bolts.
Nutrunners can be pistol-grip or angle drive types, and may or may not have a clutch. This category includes
two-speed and crow-foot nut runners; these terms are defined by ISO 5391
3.2.3
impact wrench
rotary power tool, with a reversible spindle driving a hammer which periodically strikes an anvil which includes
a drive adapter for the purpose of tightening or loosening nuts and bolts without producing any major torque
reaction on the power tool.
Impact wrenches can be straight, pistol or angle drive types and may or may not be torque controlled; these
terms are defined by ISO 5391
3.2.4
air-hydraulic impulse wrench
nutrunner where the torque for tightening or loosening threaded fasteners is obtained by a hydraulic impulse
mechanism.
Air-hydraulic impulse wrenches have the same types as impact wrenches
3.2.5
fastener installation tool
screwdriver with a reverse mechanism and a threaded drive spindle for installing threaded captive fasteners;
may be straight, pistol-grip or angle drive type
3.2.6
open-ended spanner
nutrunner or a ratched wrench with an open end socket
NOTE In US the term "Tube wrench" is used.
3.2.7
reaction bar
mechanical device for absorption of the reaction torque
3.2.8
ratchet wrench
angle drive wrench which progressively rotates a socket by means of ratchet and pawl coupling
3.2.9
rated speed, r/min
maximum rotational speed of the machine spindle, in revolutions per minute under operating conditions with
the inserted tool mounted and at the upper limit of the energy supply, e.g. pressure or flow, as specified by the
manufacturer.
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For other terms, see EN 1070 and also ISO 3857-3 and ISO 5391. For examples of assembly power tools for
threaded fasteners see annex A
4 List of hazards
The following hazards can occur in the use of assembly power tools for threaded fasteners.
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Hazard type Reference to safety requirement
By design or Information
guarding for use
4.1 Mechanical hazards
- crushing 5.7.1. 6.2.2
- cutting 5.1.1
- drawing in or trapping (caused by hair, clothing 6.2.2
etc. getting entangled in a rotating power tool)
- friction or abrasion hazard
5.1.1
- loss of stability
5.1.2
- whipping hose
6.2.2
- ejection from high pressure hydraulic systems
5.1.3
- ejection of parts
6.2.2
- hose and hose coupling specifications
6.2.2
4.2 Electrical hazards 6.2.2
4.3 Thermal hazards
- explosions 5.2
- health damage due to hot or cold surfaces 5.2
4.4 Hazards caused by noise 5.3 6.2.2
4.5 Hazards generated by vibration 5.4 6.2.2
- hazards caused by the operator putting hands on 6.2.2
the nut-running socket
4.6 Hazards generated by materials and
substances processed, used or exhausted
- exhaust air
5.5.1
- lubricants
5.5.2
- hydraulic fluid
6.2.2
4.7 Hazards caused by neglecting ergonomic
principles
- repetitive strain injuries
5.6.1, 5.6.3, 5.6.4 6.2.2
- unsuitable postures
6.2.2
- inadequate grip design and tool balance
5.6.1
- effects of reaction forces upon operator
5.6.2
- neglected use of personal protection equipment
6.2.2
4.8 Hazards caused by failure of energy supply
- unexpected return of energy supply after a 6.2.2
breakdown
- incorrect hydraulic fluid flow and outlet pressure
6.2.2
4.9 Hazards caused by missing and/or incorrectly
positioned safety related means
- start and stop device
5.7.1
- unintentional start
5.7.2 6.2.2
- unintentional locking
5.7.3
- start in unexpected direction
5.7.4
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5 Safety requirements and measures
5.1 Mechanical safety
5.1.1 Surfaces, edges and corners
Accessible parts of assembly power tools for threaded fasteners, except the inserted tool, shall not have sharp
edges or angles or rough or abrasive surfaces, see 3.1 of EN 292-2:1991.
5.1.2 Supporting surface and stability
Assembly power tools for threaded fasteners shall be so designed that they can be laid aside and remain in
stable position on a plane surface.
5.1.3 High pressure ejection
Hydraulic systems of the power tools shall be enclosed so as to give protection against high pressure fluid
ejection.
5.1.4 Guards
Guards covering the inserted tool are not required.
5.2 Thermal safety
Surface temperatures of parts of the power tools which are held during use or could be inadvertently touched
shall follow the provisions of EN 563.
NOTE The limit values for low temperatures are studied by CEN/TC 122.
Power tools for use in potentially explosive atmospheres should comply with EN 1127-1. However because
the suitability of a power tool for use in potentially explosive atmospheres will depend not only on the power
tool but the inserted tool and the workpiece, it is not possible to give any detailed advice in this standard.
5.3 Noise
5.3.1 General
The emission of noise from a hand-held power tool shall be kept as low as possible.
The noise emission from using hand-held power tools emanates from three main sources:
the hand-held power tool itself,
the inserted tool,
the workpiece.
NOTE Generally, the manufacturer has no possibility of influencing the noise emitted by the processed workpiece.
5.3.2 Noise emitted by the hand-held power tool
The noise emitted by the hand-held power tool itself can be divided into:
noise from the motor,
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noise from exhaust air or gases at pneumatic tools,
vibration induced noise.
The noise from the exhaust of air and gases is one major contributor of noise from pneumatic driven hand-
held power tools. A silencer of good design will reduce this noise.
The principles contained in EN ISO 11688-1 should be followed to reduce the noise emitted by the power tool.
NOTE The exhaust air or gases can also be piped away in a hose away from the operator, however this method has
limitations in practice.
Vibration induced noise can be reduced by use of acoustic isolation and vibration damping.
5.4 Vibration
Vibration at the handle of a hand-held power tool shall be kept as low as possible.
The principles contained in CR 1030-1 should be followed to reduce the vibration emitted by the power tool.
5.5 Materials and substances processed, used or exhausted
5.5.1 Exhaust air or gas
For assembly power tools for threaded fasteners driven with compressed air or gas or by an internal
combustion engine the exhaust air or gases shall be directed in such a way that it cannot cause a hazard to
the operator and so that any secondary effects are minimized. e.g. blowing the dust and reflected air or gas
from the workpiece onto the operator.
5.5.2 Lubricants
Lubricants for assembly power tools for threaded fasteners, specified by the manufacturer, shall not cause
hazards to the operator or the environment.
5.6 Ergonomics
5.6.1 Design of the handle
Handles and other parts used for gripping the power tool shall be designed to ensure that the operator is able
to grip the assembly power tool for threaded fasteners correctly and to perform the expected work. Handles
shall suit the functional anatomy of the hand and the dimensions of the hands of the operator population. See
3.6 of EN 292-2:1991 and EN 614-1.
Power tools having a mass greater than 2 kg (including the inserted tool) shall be capable of being supported
by two hands whilst being lifted or operated.
The grip shall be such that normal feed force and reaction torque can be transmitted in an ergonomically
suitable way from the power tool to the hand of the operator. A grip which allows ventilation may prevent the
tool from slipping.
The strength of a removable handle and the nature of fixing it shall be appropriate to the intended principal
use.
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5.6.2 Reaction torque absorption
Screwdrivers and nutrunners shall be designed to reduce the effect of the reaction torque as much as
possible. The reaction torque can be absorbed by mechanical means, such as support handle, reaction bar or
suspension arms. The reaction torque with respect to time (the torque impulse) varies depending on the
power of the power tool, clutch characteristics, joint characteristics and torque size. Therefore no general rules
can be given that prescribe the use of reaction torque absorption devices.
Screwdrivers and nutrunners that can be foreseen to be used in such operations where a harmful reaction
torque has to be absorbed by the operator shall have provisions for the attachment of absorbing devices
(support handles, reaction bars). Reaction bars shall be designed to withstand the strain that can be exerted
upon them.
Straight rotary tools shall have provisions for mounting a second handle, when the reaction torque is over
4 Nm.
Pistol grip tools shall have a provision for mounting a second handle, when the reaction torque is over 10 Nm.
1
1a Reaction bar
2
1b Support handle
1c Suspension arm
Key
1 reaction bar
2 support handle
Figure 1 — Example of methods for reaction torque absorption
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5.6.3 Control device
The control device shall be adapted to the handle or to the part of the power tool being gripped by the
operator so that it can be held comfortably in the run position.
For power tools which are normally are started frequently or are intended to be used for precision works the
trigger force should be small.
For power tools which are normally used in operations of long duration the force to keep the start device in the
run position should be small.
For further information on trigger forces for control devices see EN 894-3:2000.
5.6.4 Suspension device
Provision shall be made, where appropriate, to enable the attachment to the power tool of a suspension
device. The fitting of a suspension device shall not introduce an additional hazard.
5.7 Safety related measures and means
5.7.1 Start and stop device
Assembly power tools for threaded fasteners shall be equipped with a single control device to start or stop
them. It shall be arranged near the handle so that the operator can activate it without releasing the grip on the
handles.
The start and stop device shall be so designed that the inserted tool ceases to be powered when the start and
stop device is released. Without manual effort it shall, when released, move to the stop position, i.e. be of the
type "hold to run".
The start and stop device shall be in the stop position or immediately move to the stop position when the
assembly power tool for threaded fasteners is connected to the energy supply.
It shall not be possible to lock the start and stop device in the running position.
As an exception for assembly power tools with a capacity to tighten fasteners having a thread size of 8 mm or
less, the start and stop device may be designed to be locked in the on-position, provided it can easily be
unlocked without relinquishing hold of the power tool.
The start and stop device shall be so positioned or guarded that it cannot be unintentionally (or inadvertently)
locked. See figure 2.
1
Key
1 suitable position: the control device is placed on the upper side of the handle
Figure 2 — Example of positions of control devices for angle nut runners
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SIST EN 792-6:2000+A1:2008
EN 792-6:2000+A1:2008 (E)
5.7.2 Unintentional start
The start and stop device for open-ended spanners shall be so designed, positioned or guarded that the risk
of unintentional start is minimized. Verification shall be made according to clause 7.3.
Open ended spanners shall have a starting device requiring two separate and dissimilar actions to start.
5.7.3 Directional control device
An assembly power tool starting in a
...
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