SIST EN 792-7:2002
(Main)Hand-held non-electric power tools - Safety requirements - Part 7: Grinders
Hand-held non-electric power tools - Safety requirements - Part 7: Grinders
This European Standard applies to hand-held non-electric power tools driven by rotary or linear motors, powered by compressed air or hydraulic fluid and intended to be used by one operator and supported by:
- the operator's hand or hands;
- a harness;
- a suspension, e. g. a balancer.
This European Standard applies to hand-held non-electric power tools intended for grinding and cutting-off, with bonded, coated and super abrasive products for use on all kinds of materials.
This European Standard lists the significant hazards caused by such power tools and specifies safety requirements valid for different aspects of safety during their foreseeable lifetime.
This part of the standard covers power tools used with:
- abrasive products with a peripheral operating speed less than or equal to 80 m/s;
- cutting-off wheels with a peripheral operating speed less than or equal to100 m/s;
- abrasive products with outside nominal diameter less than or equal to 230 mm;
- cutting-off wheels with outside nominal diameter less than or equal to 300 mm;
- wire brushes.
Handgehaltene nicht-elektrisch betriebene Maschinen - Sicherheitsanforderungen - Teil 7: Schleifmaschinen für Schleifkörper
Diese Europäische Norm gilt für handgehaltene nicht-elektrisch betriebene Maschinen, die durch Motore mit drehender oder linearer Bewegung angetrieben werden, wobei die Energie aus Druckluft oder über Hydaulik-flüssigkeit bezogen werden kann. Die Maschinen sind dazu bestimmt, durch eine Person verwendet und
3 mit einer oder beiden Händen gehalten,
3 in einer Einspannvorrichtung aufgenommen,
3 in einer Halterung, z. B. Aufhängevorrichtung, aufgenommen
zu werden.
Diese Europäische Norm gilt für handgehaltene nicht-elektrisch betriebene Maschinen zum Schleifen und Trennen, mit gebundenen, beschichteten und Hochleistungs-Schleifkörpern für alle Materialarten.
Diese Europäische Norm 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:
3 Schleifmaschinen für Schleifkörper mit Umfangsgeschwindigkeit von 80 m/s oder weniger;
3 Trennscheiben mit Umfangsgeschwindigkeit von 100 m/s oder weniger;
3 Schleifkörper mit äußeren Maßen von 230 mm Durchmesser oder weniger;
3 Trennscheiben mit äußeren Maßen von 300 mm Durchmesser oder weniger;
3 Maschinen mit Drahtbürsten.
Diese Europäische Norm gilt nicht für:
3 Schleifmaschinen für Schleifstifte, siehe EN 792-9
3 Schleifmaschinen für Schleifblätter und Polierer, siehe EN 792-8
3 Trennschleifmaschinen für das Bau- oder Rettungswesen, die durch einen Verbrennungsmotor angetrieben werden, siehe EN 1454
Diese Europäische Norm gilt nicht für Schleifmaschinen für Schleifkörper, die durch einen Verbrennungsmotor angetrieben werden.
Typische Schleifprodukte, die zusammen mit handgehaltenen Schleifmaschinen verwendet werden, sind in Anhang C aufgelistet.
Besondere Anforderungen und Änderungen an handgehaltene Maschinen zum Zwecke des Spannens in einer Halterung, werden in diesem Teil nicht beh
Machines portatives a moteur non électrique - Prescriptions de sécurité - Partie 7: Meuleuses
La présente Norme européenne s'applique aux machines portatives non électriques entraînées par des moteurs rotatifs ou linéaires, alimentés par air comprimé, fluide hydraulique et prévues pour etre utilisées par un seul opérateur et portée par :
3 la ou les main(s) de l'opérateur ;
3 un harnais ;
3 en suspension, par exemple a l'aide d'un équilibreur.
La présente Norme européenne s'applique aux machines portatives non électriques utilisées pour le meulage et le tronçonnage de toutes sortes de matériaux, a l'aide de produits abrasifs ; elle spécifie les prescriptions de sécurité qui s'y rapportent.
La présente Norme européenne énumere les risques significatifs provoqués par de telles machines portatives et spécifie les prescriptions de sécurité relatives aux différents aspects de sécurité pouvant etre rencontrés pendant leur durée de vie prévisible.
La présente partie de norme couvre les types de machines portatives utilisées avec:
3 des produits abrasifs dont la vitesse périphérique de travail est inférieure ou égale a 80 m/s ;
3 meules de tronçonnage dont la vitesse périphérique de travail est inférieure ou égale a 100 m/s ;
3 des produits abrasifs dont le diametre nominal extérieur inférieur ou égal a 230 mm ;
3 meules de tronçonnage dont le diametre nominal extérieur est inférieur ou égal a 300 mm ;
3 des brosses métallique.
La présente Norme européenne ne s'applique pas aux:
3 meuleuses d'outillage avec pince de serrage qui font l'objet de l'EN 792-9 ;
3 polisseuses-lustreuses et ponceuses qui font l'objet de l'EN 792-8 ;
3 machines de tronçonnage, pour la construction et le sauvetage, mues par un moteur a combustion interne qui font l'objet de l'EN 1454.
Il n'y a pas de meuleuses couvertes par la présente partie de la norme mues par un moteur a combustion interne.
Neelektrična ročna orodja - Varnostne zahteve - 7. del: Brusilniki
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 792-7:2002
01-november-2002
1DGRPHãþD
SIST EN 68:2000
SIST EN 68:2000/A1:2000
1HHOHNWULþQDURþQDRURGMD9DUQRVWQH]DKWHYHGHO %UXVLOQLNL
Hand-held non-electric power tools - Safety requirements - Part 7: Grinders
Handgehaltene nicht-elektrisch betriebene Maschinen - Sicherheitsanforderungen - Teil
7: Schleifmaschinen für Schleifkörper
Machines portatives a moteur non électrique - Prescriptions de sécurité - Partie 7:
Meuleuses
Ta slovenski standard je istoveten z: EN 792-7:2001
ICS:
25.140.10 3QHYPDWLþQDRURGMD Pneumatic tools
SIST EN 792-7:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 792-7:2002
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SIST EN 792-7:2002
EN 792-7:2001 (E)
CONTENTS
page
Foreword 3
0 Introduction 4
1 Scope 5
2 Normative references 5
3 Terms and definitions 6
3.1 General terms and definitions 7
3.2 Terms and definitions related to grinders 7
4 List of significant hazards 9
5 Safety requirements and measures 10
5.1 Mechanical safety 10
5.2 Thermal safety 13
5.3 Noise 13
5.4 Vibration 14
5.5 Materials and substances processed, used or exhausted 14
5.6 Ergonomics 14
5.7 Safety related measures and means 15
6 Information for use 16
6.1 Marking, signs and written warnings 16
6.2 Instruction for use 16
7 Verification 20
7.1 Noise 20
7.2 Vibration 20
7.3 Test of deformation of flanges 20
7.4 Test of guards 21
7.5 Unintentional start 23
7.6 Structure of verification of safety requirements 24
Annex A (informative) Examples of grinders covered by this standard 26
Annex B (informative) Symbols for labels and signs 27
Annex C (informative) List of abrasive products for hand-held grinders 28
Annex D (normative) Design, material and thickness of guards 33
Annex E (informative) Example of calculating procedure of clamping force 39
Annex F (informative) Example of flanges 42
Annex ZA (informative) Relationship of this European Standard with EC Directives 48
Bibliography 49
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SIST EN 792-7:2002
EN 792-7:2001 (E)
Foreword
This European Standard 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 June 2002, and conflicting national standards
shall be withdrawn at the latest by June 2002.
This European Standards supersedes EN 68:1977.
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 annex ZA, which is an integral part of this
standard.
The "European Committee of Manufacturers of Compressors, Vacuum Pumps and Pneumatic
Tools", PNEUROP, has given substantial contributions to this standard.
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.
NOTE Other technical committees in CEN dealing with hand-held power tools have been asked to follow
the safety requirements as in EN 792.
The annexes to this part of the standard are:
Annex A (informative) Examples of grinders covered by this standard
Annex B (informative) Symbols for labels and signs
Annex C (informative) List of abrasive products for hand-held grinders
Annex D (normative) Design, material and thickness of guards
Annex E (informative) Example of calculating procedure of clamping force
Annex F (informative) Example of flanges
Annex ZA (informative) Relationship of this European Standard with EC Directives.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.
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SIST EN 792-7:2002
EN 792-7:2001 (E)
0 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.
EN 792 consists of a number of independent parts for individual types of hand-held non-electric
power tools.
Other European 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.
4
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SIST EN 792-7:2002
EN 792-7:2001 (E)
1 Scope
This European Standard applies to hand-held non-electric power tools driven by rotary or linear
motors, powered by compressed air or hydraulic fluid and intended to be used by one operator
and supported by:
- the operator's hand or hands;
- a harness;
- a suspension, e. g. a balancer.
This European Standard applies to hand-held non-electric power tools intended for grinding and
cutting-off, with bonded, coated and super abrasive products for use on all kinds of materials.
This European Standard lists the significant hazards caused by such power tools and specifies
safety requirements valid for different aspects of safety during their foreseeable lifetime.
This part of the standard covers power tools used with:
- abrasive products with a peripheral operating speed less than or equal to 80 m/s;
- cutting-off wheels with a peripheral operating speed less than or equal to100 m/s;
- abrasive products with outside nominal diameter less than or equal to 230 mm;
- cutting-off wheels with outside nominal diameter less than or equal to 300 mm;
- wire brushes.
This Part of the standard does not apply to:
- die grinders with collets which are treated in EN 792-9;
- polishers and sanders which are treated in EN 792-8;
- cutting-off machines used for construction, rescue purposes which are driven by an
internal combustion engine which are treated in EN 1454.
There are no grinders covered by this Part of this European Standard driven by internal
combustion engines.
Typical abrasive products used together with hand-held grinders are listed in annex C.
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 grinders 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).
5
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SIST EN 792-7:2002
EN 792-7:2001 (E)
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.
CR 1030-1, Hand-arm vibrations - Guidelines for vibration hazards reduction - Part 1:
Engineering methods by design of machinery.
EN 1127-1, Explosive atmospheres – Explosion prevention and protection – Part 1: Basic
concepts and methodology.
EN 10111, Continuously hot-rolled low carbon sheet and strip for cold bending - Technical
delivery conditions.
EN 10130, Cold rolled low carbon steel flat products for cold forming - Technical delivery
conditions.
EN 12096, Mechanical vibration - Declaration and verification of vibration emission values.
EN 28662-1, Hand-held portable power tools - Measurement of vibration at the handle -Part 1:
General (ISO 8662–1:1998).
EN ISO 4871, Acoustics - Declaration and verification of noise emission values of machinery and
equipment.
EN ISO 8662-4, Hand-held portable power tools - Measurement of vibration at the handle -Part 4:
Grinders.
EN ISO 11688-1, Acoustics - Recommended practice for the design of low-noise machinery and
equipment - Part 1: Planning (ISO/TR 11688-1:1995).
EN ISO 11688-2, Acoustics - Recommended practice for the design of low-noise machinery and
equipment - Part 2: Introduction to the physics of low-noise design (ISO/TR 11688-2:1998).
EN ISO 14163, Acoustics - Guidelines for noise control by silencers (ISO 14163:1998).
prEN ISO 15744, Hand-held non-electric powertools – Noise measurement code – Engineering
method (grade 2) (ISO/DIS 15744:1999).
ISO 525, Bonded abrasive products - General requirements.
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
6
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EN 792-7:2001 (E)
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
3.2 Terms and definitions related to grinders
3.2.1
grinder
power tool driving a rotating spindle on which an abrasive product is mounted
NOTE A grinder equipped with a cutting off wheel is often called a cutting off machine.
3.2.2
machine spindle
shaft of the grinder which supports, locates and drives the abrasive product
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EN 792-7:2001 (E)
3.2.3
rated speed, r/min
maximum rotational speed of the machine spindle, in revolutions per minute under operating
conditions with the abrasive product mounted and at the upper limit of the energy supply, e.g.
pressure or flow, as specified by the manufacturer
3.2.4
maximum operating speed
maximum peripheral speed of an abrasive product, given in m/s, as specified by the
manufacturer of the abrasive product
3.2.5
flange
disc, normally of metal, mounted on the machine spindle to support and clamp the abrasive
product
3.2.6
flange set
means provided to clamp an unthreaded abrasive product, on the rotating machine spindle
3.2.7
backing flange
flange fixed to the machine spindle and having an unrecessed flat surface against which an
abrasive product is screwed, e.g. a cup wheel, a cone or a plug
NOTE The terms backing, back flange or fixed flange are terms also used.
3.2.8
flange contact diameter, d
f
outside diameter of the contact surface of a flange
3.2.9
guard
device which partly encloses the abrasive product
3.2.10
blotter
thin piece of a compressible material placed between the abrasive product and the flange of the
grinder
3.2.11
tightening torque
torque for tightening the clamping device to fasten the abrasive product to the machine spindle
For other terms, see EN 1070 and also ISO 3857-3 and ISO 5391. For examples of grinders see
annex A.
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EN 792-7:2001 (E)
4 List of significant hazards
The following significant hazards can occur in the use of grinders.
Table 1 - List of significant hazards
Significant hazard type Reference to safety requirement
By design or Information for
guarding use
4.1 Mechanical hazards
- cutting 5.1.1, 5.1.3
- drawing in or trapping (caused by hair, clothing etc. 5.1.6 6.2.2
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 5.1.4
- ejection of parts due to:
. cracked abrasive product 5.1.6 6.2.2
. incorrect mounting of the abrasive product 5.1.7, 5.1.8
. misuse of grinder 6.2.2
. overspeed of grinder 5.1.5
. use of incorrect flanges 5.1.9
. use of wrong abrasive product 6.2.2
- hose and hose coupling specifications 6.2.2
4.2 Electrical hazards 6.2.2
4.3 Thermal hazards 5.2
- explosions
6.2.2
- 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
4.6 Hazards generated by materials and substances
processed, used or exhausted
- inhalation of harmful dust 5.5.2
- formation of explosive dust 6.2.2
- sparks 6.2.2
- exhaust air 5.5.1 6.2.2
- lubricants 5.5.3
- hydraulic fluid 6.2.2
4.7 Hazards caused by neglecting ergonomic principles
- repetitive strain injuries
5.6.1 6.2.2
- unsuitable postures
5.6.1, 5.6.2, 5.6.3,
- inadequate grip design and tool balance
5.6.1 6.2.2
- neglected use of personal protection equipment
5.6.1 6.2.2
4.8 Hazards caused by failure of energy supply
- unexpected return of energy supply after a breakdown 6.2.2
- 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
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SIST EN 792-7:2002
EN 792-7:2001 (E)
5 Safety requirements and measures
5.1 Mechanical safety
5.1.1 Surfaces, edges and corners
Accessible parts of the power tool, except the insert 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
The power tool shall be so designed that it can be laid aside and remain in stable position on a
plane surface.
5.1.3 Run-down time
The run-down time, after the stop command has been given, shall be as short as possible.
5.1.4 High pressure ejection
Hydraulic systems of the power tool shall be enclosed so as to give protection against high
pressure fluid ejection.
5.1.5 Speed control
The rated speed of the grinder shall not be exceeded under the conditions marked on the power
tool. It shall be possible to measure rotational speed by a tachometer.
At no load, the speed may exceed the rated speed by no more than 10 % at rated input values
and with an unworn wheel mounted.
The speed control device of a grinder shall be designed to prevent incorrect assembly. The
speed control device shall be manufactured of non-corrodable material.
5.1.6 Guards
Grinders shall be equipped with guards to protect against:
- accidental contact with the abrasive product;
- ejection of fragments of the abrasive product;
- sparks and debris.
Guards are not mandatory, but recommended, for cones and plugs with the diameter less than
50 mm and for wire brushes
For internal grinding guards are not needed.
The guards shall fulfil the following requirements:
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EN 792-7:2001 (E)
- be designed so that in case of an abrasive product burst the guard shall reduce the risk of
injury to the operator and remain attached to the grinder
- be located so that the risk of accidental contact between the operator and the abrasive
product during intended use is minimized
- the clearance between the inside of the guard and the periphery of a new
abrasive product shall be:
max. 8 mm and min. 3 mm for nominal diameter 125 mm
max. 10 mm and min. 6 mm for nominal diameter > 125 mm
The design, material and thickness of guards is specified in annex D.
If the specification of design, material and thickness in annex D is not followed, the guard shall
withstand the test as specified in 7.4.
If other material than steel plate is used, it shall be equally suitable for all working conditions.
5.1.7 Attachment of abrasive product
The grinder shall be designed to prevent the abrasive product coming loose, for instance
unscrewed by inertia and spinned off, after the stop comment has been given.
5.1.8 Spindles
Spindles shall be designed so that they locate the abrasive product. Machine spindles shall be
made resistant to impact.
The direction of the spindle threads shall be such that any clamping device, collet or wheel with
threaded hole shall tend to tighten during grinding.
0,05 0,1
2
1
Key
1 Machine spindle
2 Machine spindle with threads
Figure 1 - Maximum spindle run-out
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SIST EN 792-7:2002
EN 792-7:2001 (E)
For spindles, that locates a plain bore wheel, the diameter shall have the tolerance of
concentricity of 0,05 mm maximum total indicator reading to the true running centre of the
spindle. See Figure 1.
For spindles with a threaded portion intended for locating abrasive products with threaded bores,
the pitch diameter of the thread shall have the tolerance of concentricity of effective diameter of
0,1 mm maximum total indicator reading to the true axis of the spindle.
The diameter of the part, which locates the abrasive product shall have a tolerance of e8 or
better.
For grinders intended to be used with threaded hole wheels, the manufacturer shall give
information of the spindle thread size on the grinder, preferably on the spindle.
5.1.9 Flanges
Flanges shall be designed that they clamp and locate each type of abrasive product securely to
the grinder and provide true running under operation.
Flanges shall be tested for deformation under load according to 7.3.
Annex E can serve as a base for the calculation of flanges and the tightening torque.
Annex F gives the principle design of flanges and will at the revision be completed with calculated
dimensional values.
Flanges in a set shall have the same contact diameter and shall have equal contact surface,
except for abrasive products of types 27, 28 and 42 which are allowed to use a backing flange
with a diameter larger than that of the clamping nut, see Figures F.7 a) and F.7 b).
For grinding wheel type 41 the flanges shall have the same external diameter and the backing
flange may have a larger contact surface than the outer flange. See Figure F.7 c).
Backing flanges (normally fixed) may have a larger contact surface than the outer flange if this
arrangement fulfils the requirement of absorbing the grinding forces (type S 6 and 11) See Figure
F.3.
All flanges shall have a chamfer or recess around the centre hole to prevent pieces of the
abrasive product from splintering due to high edge pressure arising when clamping it. See Figure
2. Backing flanges to be used with threaded bore abrasive products shall not be recessed,
unless the abrasive product has a riveted anchor plate. See Figures F.4 and F.5.
Figure 2 - Example of chamfer or recess on a flange
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SIST EN 792-7:2002
EN 792-7:2001 (E)
At least one of the flanges shall be keyed, screwed, shrunk or otherwise secured to prevent
rotation relative to the machine spindle.
The contact surface of the flanges (both set of flanges and backing flanges) shall run true with a
tolerance giving a total indicator reading of max. 0,1 % of the diameter at the position of the
indicator. The indicator shall be positioned near the outside diameter.
2
The steel in the flanges shall have a minimum tensile strength of 430 N/mm . Other materials
may be used, in which case the flange shall be tested and fulfil the requirement of clause 7.3.
The part of the flanges which locates and guides the abrasive products with unthreaded holes
shall have the same tolerances as specified in 5.1.8.
5.2 Thermal safety
Parts of the grinder which are held during use or can be inadvertently touched shall follow the
provisions of EN 563.
Low temperatures shall be avoided by design.
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:
- noise from exhaust air at pneumatic tools:
- vibration induced noise.
The noise from the exhaust of air is one major contributor of noise from pneumatic driven hand-
held power tools. A silencer, conforming to EN ISO 14163, of good design will reduce this noise.
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EN 792-7:2001 (E)
The principles contained in EN ISO 11688-1 and EN ISO 11688-2 should be followed to reduce
the noise emitted by the power tool.
NOTE The exhaust air can also be piped away in a hose away from the operator, however this method has
limitations in practice.
To control the radiation of structure borne noise, vibration isolation and additional damping close
to the source can be applied.
To control the air borne noise emission caused by the radiation of structure borne noise, vibration
isolation and additional damping close to the source can be applied.
The criterion for assessing the efficiency of noise reduction measures are the actual noise
emission values from the machine in relation to other machines of the same family and not the
nature of the reduction measures themselves.
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
For grinders driven with compressed air the exhaust air 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 Dust
It shall be possible to connect to grinders a dust collecting device or to use a dust suppression
device.
NOTE Because the risks arising from dust will depend on the materials being processed it is not possible
to give technical requirements for collection and disposal of the dust in this standard.
5.5.3 Lubricants
Lubricants for grinders, 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 grinder shall be designed to ensure that the
operator is able to grip the grinder 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.
Angle and vertical grinders shall have provision for mounting a second handle, when the power
out put is over 0,5 kW.
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EN 792-7:2001 (E)
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 strength of a removable handle and the nature of fixing it shall be appropriate to the intended
principal use.
5.6.2 Control device
The control device shall be adapted to the handle so that it can be held in the run position.
For grinders, which are intended to be started frequently or are intended to be used for precision
work, the trigger force shall be small.
For grinders which are normally used in operations of long duration the force to keep the start
device in the run position shall be small.
For further information on trigger forces for control devices, see EN 894-3.
5.6.3 Suspension device
Provision shall be made, where appropriate, to enable the attachment to the grinder 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
Grinders 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 grinder is connected to the energy supply.
It shall not be possible to lock the start and stop device in the running position.
5.7.2 Unintentional start
The start and stop device shall be so designed, positioned or guarded that the risk of
unintentional start is avoided.
Two separate and dissimilar actions to start the grinder are required for:
- angle grinders intended for wheels with a nominal diameter exceeding
125 mm;
- straight grinders intended for wheels with a nominal diameter exceeding;
100 mm;
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EN 792-7:2001 (E)
- vertical grinders intended for wheels with a nominal diameter exceeding
100 mm.
Verification shall be made according to 7.5.
6 Information for use
6.1 Marking, signs and written warnings
Grinders shall be marked with the following information:
- name and address of the manufacturer;
- designation of series or type;
- serial number or batch number;
- year of manufacture;
- the rated rotational speed of the spindle, in revolutions per minute (r/min);
- maximum operating pressure for pneumatic tools or maximum pressure and flow; for
hydraulic tools;
- the spindle thread size. (Marking can preferably be made on the spindle itself. This
concerns grinders intended for use with threaded hole wheels).
The direction of rotation shall be permanently marked by an arrow.
Grinders shall be permanently marked with a graphical symbol, stating that the operator's
instruction shall be read before work starts, according to annex B.
Other graphical symbols that can be used are shown in annex B.
6.2 Instruction for use
6.2.1 General
The instructions for use shall be drawn up by the manufacturer and contain:
- operator's instruction;
- maintenance instructions.
The operator's instructions shall be drawn up according to 5.5.2, A.1.7.4 and A.2.2 of EN
292-2:1991. Concerning residual risks see 5.5 of EN 292-1:1991.
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6.2.2 Operator's instruction
a) General precautions
The operator's instruction shall include a description of the correc
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