SIST EN 746-3:2000+A1:2009
(Main)Industrial thermoprocessing equipment - Part 3: Safety requirements for the generation and use of atmosphere gases
Industrial thermoprocessing equipment - Part 3: Safety requirements for the generation and use of atmosphere gases
This part of EN 746 specifies safety requirements for atmosphere gas systems and their use in industrial thermo-processing equipment and associated plant, including systems for the production of atmosphere gases by reaction inside the thermo-processing equipment.
It applies to the supply of atmosphere gases, gaseous and liquid additions to, and their removal from industrial thermo-processing equipment and associated plant, confined to equipment integrated in the thermo-processing and associated plant.
This part of EN 746 also details the anticipated significant hazards associated with atmosphere gas systems and their use in industrial thermo-processing equipment and specifies the appropriate preventative measures for the reduction or elimination of these hazards.
This part of EN 746 does not apply to atmosphere process gases, essential safety equipment, start-up, operation and shut-down of thermo-processing plant for semi-conductor devices for which special additional engineering requirements are necessary.
This part of EN 746 specifies the requirements to be met to ensure the safety of persons and property during commissioning, start up, operation, shut down and maintenance, as well as in the event of foreseeable faults or malfunctions which can occur in the equipment. It specifies the safety requirements at stages in the life of the equipment, and its design, ordering, construction and use.
This part of EN 746 applies to equipment which is placed on the market after the date of issue of this standard.
The hazards covered by this Part of EN 746 are listed in clause 4.
A table of typical atmosphere gases is given in Annex A.
Industrielle Thermoprozessanlagen - Teil 3: Sicherheitsanforderungen für die Erzeugung und Anwendung von Schutz- und Reaktionsgasen
Equipements thermiques industriels - Partie 3: Prescriptions de sécurité pour la génération et l'utilisation des gaz d'atmosphère
La présente partie de l'EN 746 fixe les prescriptions de sécurité pour les systèmes à gaz d'atmosphère et leur
utilisation dans les équipements thermiques industriels et usines associées, y compris les systèmes de production
de gaz d'atmosphère par réaction à l'intérieur de l'équipement thermique industriel.
La présente partie de l'EN 746 s'applique à l'alimentation de gaz d'atmosphère, à des adjonctions gazeuses
et liquides et à leur rejet de l'équipement thermique industriel et de l'usine associée, restreint à l'équipement intégré
à l'équipement de traitement thermique et à l'usine associée.
La présente partie de l'EN 746 décrit également en détail les risques significatifs identifiés dans les systèmes à gaz
d'atmosphère et de leur utilisation dans les équipements thermiques industriels et indique les mesures préventives
adaptées, permettant de limiter, voire d'éliminer ces risques.
La présente partie de l'EN 746 ne s'applique pas aux gaz d'atmosphère de traitement, à l'équipement de sécurité
principal et au démarrage, au fonctionnement et à l'arrêt des installations de traitement thermique pour dispositifs
à semi-conducteur, ceux-ci nécessitant des prescriptions supplémentaires en matière d'ingénierie.
La présente partie de l'EN 746 indique les prescriptions à suivre pour garantir la sécurité des personnes et des biens
lors de la mise en service, du démarrage, du fonctionnement, de l'arrêt et de la maintenance, ainsi que dans
l'éventualité d'une panne ou d'un dysfonctionnement qui peut se produire au niveau de l'équipement. Elle indique les
prescriptions en matière de sécurité, à différentes étapes de la vie de l'équipement ainsi que lors des phases de
conception, de commande, de fabrication et d'utilisation.
La présente partie de l'EN 746 s'applique à tout équipement mis sur le marché après la date de publication de
la norme.
Les risques traités dans cette partie de l'EN 746 sont énumérés à l'Article 4.
Industrijska termoprocesna oprema - 3. del: Varnostne zahteve za pridobivanje in uporabo atmosferskih plinov
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 746-3:2000+A1:2009
01-september-2009
Industrijska termoprocesna oprema - 3. del: Varnostne zahteve za pridobivanje in
uporabo atmosferskih plinov
Industrial thermoprocessing equipment - Part 3: Safety requirements for the generation
and use of atmosphere gases
Industrielle Thermoprozessanlagen - Teil 3: Sicherheitsanforderungen für die Erzeugung
und Anwendung von Schutz- und Reaktionsgasen
Equipements thermiques industriels - Partie 3: Prescriptions de sécurité pour la
génération et l'utilisation des gaz d'atmosphère
Ta slovenski standard je istoveten z: EN 746-3:1997+A1:2009
ICS:
25.180.01 ,QGXVWULMVNHSHþLQDVSORãQR Industrial furnaces in general
SIST EN 746-3:2000+A1:2009 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN 746-3:2000+A1:2009
---------------------- Page: 2 ----------------------
SIST EN 746-3:2000+A1:2009
EUROPEAN STANDARD
EN 746-3:1997+A1
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2009
ICS 25.180.01 Supersedes EN 746-3:1997
English Version
Industrial thermoprocessing equipment - Part 3: Safety
requirements for the generation and use of atmosphere gases
Equipements thermiques industriels - Partie 3: Industrielle Thermoprozessanlagen - Teil 3:
Prescriptions de sécurité pour la génération et l'utilisation Sicherheitsanforderungen für die Erzeugung und
des gaz d'atmosphère Anwendung von Schutz- und Reaktionsgasen
This European Standard was approved by CEN on 19 March 1997 and includes Amendment 1 approved by CEN on 21 May 2009.
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: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 746-3:1997+A1:2009: E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Contents Page
Foreword .3
Introduction .5
1 Scope .5
2 Normative references .6
3 Definitions .7
4 List of hazards . 10
5 Safety requirements for the use of atmosphere gases. 16
5.1 Purging . 16
5.2 Safety control equipment for atmosphere gases . 17
5.3 Thermo-processing equipment requirements . 18
6 Safety requirements for atmosphere gas generators . 22
6.1 Reaction gas supplies . 22
6.2 Fuel gas supplies . 23
6.3 Air supplies . 23
6.4 Mixture supplies. 24
6.5 Electrical supplies . 24
6.6 Cooling water supplies and discharge . 24
6.7 Atmosphere gas supplies and distribution . 25
6.8 System requirements . 25
7 Verification of the safety requirements and/or measures . 27
8 Information for use . 27
8.1 Instruction handbook . 27
8.2 Marking . 30
Annex A (informative) Typical Atmosphere Gases . 31
Annex B (informative) Explosion Hazards of Gas Mixtures Containing Combustibles . 32
Annex C (informative) Inert Gas Purging . 34
Annex D: Bibliography . 36
Annex E (informative) Used Definitions . 37
Annex ZA (informative) !Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC" . 40
Annex ZB (informative) !Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC" . 41
2
---------------------- Page: 4 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Foreword
This document (EN 746-3:1997+A1:2009) has been prepared by Technical Committee CEN/TC 186
“Industrial thermoprocessing - Safety”, 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 December 2009, and conflicting national standards shall be withdrawn
at the latest by December 2009.
This document includes Amendment 1, approved by CEN on 2009-05-21.
This document supersedes EN 746-3:1997.
The start and finish of text introduced or altered by amendment is indicated in the text by tags ! ".
The working group that drafted this Part of EN 746 comprised experts from the following countries: France,
Germany, Italy, Switzerland and the United Kingdom.
This standard forms one part of safety standards covering Industrial Thermoprocessing Equipment.
The full list of parts of this standard is given below:
EN 746 Industrial Thermoprocessing Equipment
Part 1: Common Safety Requirements for Industrial Thermoprocessing Equipment
Part 2: Safety Requirements for Combustion and Fuel Handling Systems
Part 3: Safety Requirements for the Generation and Use of Atmosphere Gases
Part 4: Particular Safety Requirements for Hot Dip Galvanising Thermoprocessing Equipment
Part 5: Particular Safety Requirements for Salt Bath Thermoprocessing Equipment
Part 6: Particular Safety Requirements for Material Melting, Remelting and Liquid Phase Maintaining
Thermoprocessing Equipment
Part 7: Particular Safety Requirements for Vacuum Thermoprocessing Equipment
Part 8: Particular Safety Requirements for Quenching Equipment
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
!For relationship with EU Directive(s), see informative Annexes ZA and ZB, which are integral parts of this
document."
An assessment of the foreseeable risks arising from the use of the equipment was carried out when this
standard was prepared.
3
---------------------- Page: 5 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
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.
4
---------------------- Page: 6 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Introduction
This standard has been prepared to be a harmonised standard to provide one means of conforming to the
Essential requirements of the Machinery Directive and associated EFTA Regulations.
The extent to which hazards are covered is indicated in the scope of this standard. In addition, machinery
shall comply as appropriate with !EN ISO 12100-1 and EN ISO 12100-2" for hazards which are not
covered by this standard.
This European Standard is a type-C standard as defined in !EN ISO 12100-1 and EN ISO 12100-2".
!EN 746-1 contains the common safety provisions for all types of industrial thermoprocessing equipment.
This part of the standard details in addition those extra safety requirements for the equipment listed in the
scope, which need special attention."
The equipment dealt with and the extent to which hazards are covered are indicated in the scope of this part
of EN 746.
Where for clarity an example of a preventative measure is given in the text, this should not be
considered as the only possible solution. Any other solution leading to the same risk reduction is
permissible if an equivalent level of safety is achieved.
This part of EN 746 assumes that the installations are operated and maintained by trained personnel.
1 Scope
This part of EN 746 specifies safety requirements for atmosphere gas systems and their use in industrial
thermo-processing equipment and associated plant, including systems for the production of atmosphere
gases by reaction inside the thermo-processing equipment.
It applies to the supply of atmosphere gases, gaseous and liquid additions to, and their removal from industrial
thermo-processing equipment and associated plant, confined to equipment integrated in the thermo-
processing and associated plant.
This part of EN 746 also details the anticipated significant hazards associated with atmosphere gas systems
and their use in industrial thermo-processing equipment and specifies the appropriate preventative measures
for the reduction or elimination of these hazards.
This part of EN 746 does not apply to atmosphere process gases, essential safety equipment, start-up,
operation and shut-down of thermo-processing plant for semi-conductor devices for which special additional
engineering requirements are necessary.
This part of EN 746 specifies the requirements to be met to ensure the safety of persons and property during
commissioning, start up, operation, shut down and maintenance, as well as in the event of foreseeable faults
or malfunctions which can occur in the equipment. It specifies the safety requirements at stages in the life of
the equipment, and its design, ordering, construction and use.
This part of EN 746 applies to equipment which is placed on the market after the date of issue of this
standard.
The hazards covered by this Part of EN 746 are listed in clause 4.
A table of typical atmosphere gases is given in Annex A.
5
---------------------- Page: 7 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
2 Normative references
!The following referenced documents are indispensable for the application 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 88-1, Pressure regulators and associated safety devices for gas appliances — Part 1: Pressure
regulators for inlet pressures up to and including 500 mbar"
EN 161, Automatic shut-off valves for gas burners and gas appliances
!deleted text"
EN 298, Automatic gas burner control systems for gas burners and gas burning appliances with or without
fans
EN 746-1, Industrial thermoprocessing equipment — Part 1: Common safety requirements for Industrial
Thermoprocessing Equipment
EN 746-2, Industrial thermoprocessing equipment — Part 2: Safety requirements for combustion and fuel
handling systems
EN 60204-1, Safety of machinery — Electrical equipment of machines — Part 1: General requirements
!(IEC 60204-1:2005, modified)"
EN 60519-1, Safety in electroheat installations — Part 1: General requirements !(IEC 60519-1:2003)"
EN 60519-2, Safety in electroheat installations — Part 2: Particular requirements for resistance heating
equipment !(IEC 660519-2:2006)"
!EN ISO 12100-1:2003, Safety of machinery — Basic concepts, general principles for design — Part 1:
Basic terminology, methodology (ISO 12100-1:2003)"
!EN ISO 12100-2:2003, Safety of machinery — Basic concepts, general principles for design — Part 2:
Technical principles (ISO 12100-2:2003)"
!IEC 60364-4-41, Low-voltage electrical installations — Part 4-41: Protection for safety — Protection
against electric shock"
!IEC 60364-43, Electrical installations of buildings — Part 4-43: Protection for safety — Protection against
overcurrent"
!deleted text"
!IEC 60364-4-44, Low-voltage electrical installations — Part 4-44: Protection for safety — Protection
against voltage disturbances and electromagnetic disturbances"
!deleted text"
!IEC 60519-3, Safety in electroheat installations — Part 3: Particular requirements for induction and
conduction heating and induction melting installations"
6
---------------------- Page: 8 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
3 Definitions
For the purposes of this standard the following definitions apply:
NOTE An alphabetic listing of the definitions, as well as their cross-references in German, French and English are
given in informative Annex E.
3.1
industrial thermo-processing and associated equipment
Any equipment through or into which the atmosphere gases flow
NOTE This includes atmosphere gas distribution systems, safety control equipment and the furnace or other
enclosures in which atmosphere gases are used.
3.2
safe ignition temperature
the minimum temperature at which spontaneous, safe auto-ignition of flammable gases occurs
NOTE The safe ignition temperature has been established at 750 °C.
3.3
purging
the general displacement of one type of atmosphere within a thermal processing plant by another
3.4
flammable atmosphere gas
any gas mixture that is capable of forming flammable mixtures with air or oxygen under the conditions of
temperature and pressure used in the process
NOTE 1 Typically any gas mixture containing more than 5% (V/V) combustibles (H +CO+CH ) of which CH is not
2 4 4
more than 1% (V/V), where the remainder of the mixture is non-flammable, is considered to be flammable. Any gas
mixture which contains more than 1% (V/V) C H or 2,5% (V/V) or 2,5% (V/V) NH where the remainder of the mixture is
n m 3
non-flammable is also considered to be flammable (see Annexes A and B).
NOTE 2 A flammable gas which contains 1 % (V/V) or less oxygen cannot in itself form an explosive or flammable
mixture.
3.5
non-flammable atmosphere gas
any gas mixture which is not capable of forming flammable mixtures with air or oxygen under the conditions of
temperature and pressure used in the process
NOTE Typically any gas mixture containing 5% (V/V) or less of combustibles (H +CO+CH ) of which CH is not more
2 4 4
than 1% of the 5% (V/V) and the remainder is non-flammable and which will not support combustion.
3.6
inert gas
a non-flammable gas which will not support combustion and does not react to produce a flammable gas
NOTE 1 An inert gas can safely be used for pre- and post-purging of cold and hot enclosures of thermo-processing
equipment.
NOTE 2 Inert gas can be produced by appropriate adjustment of an exothermic generator. In the event of malfunction
such as gas can be flammable and provisions should be taken to ensure that adjustment is correct.
3.7
toxic atmosphere gas
a gas which, in addition to having asphyxiating properties, also acts as a poison
7
---------------------- Page: 9 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
3.8
fluid
a liquid or a gas
NOTE If specific reference is made to "liquid" or "gas" this means the physical state of the fluid being considered.
3.9
safe level of vacuum
the absolute pressure of an evacuated furnace chamber/enclosure corresponding to safe atmosphere
conditions.
5
NOTE The safe level of vacuum has been established as a maximum of 45 mbar absolute (1 bar = 10 Pa).
3.10
safety purge volume
the volume of inert purge gas needed to displace either air or a flammable gas from a furnace
chamber/enclosure to achieve 1% (V/V) or less oxygen and/or a non-flammable atmosphere gas (as defined
in 3.5) and/or 25% of the lower flammability limit.
NOTE Typically this will be a volume equal to five times the volume of the thermo-processing equipment chamber to
be purged, see Annex C.
3.11
atmosphere gas generating system
equipment that converts or modifies a mixture of fluids (gaseous or liquid) into a gas which can be utilised as
the controlled atmosphere within the thermo-processing equipment.
3.12
automatic re-start
automatic repetition of the starting up sequence without manual intervention.
3.13
flame instability
undesirable variation in the size, shape and position of a flame.
3.14
flame sensor
that part of a flame safeguard or flame monitoring system that is responsive to flame properties and which
signals the presence of flame.
3.15
sensor output drift
a condition occurring within the flame sensor whereby it responds to flame characteristics outside the safety
range for which it was designed.
3.16
flame failure
loss of flame from the normally detected position by any cause other than the action of de-energising the
safety shut-off valves system (EN 746-2).
3.17
flame safeguard
a device responsive to flame properties, detecting the presence of a nominated flame and, in the event of
ignition failure or subsequent flame failure, causing safety shut-down or lock out.
It consists of a flame sensor, an amplifier and a relay for signal transmission. These parts, with the possible
exception of the actual flame sensor, may be assembled in a single housing for use in conjunction with a
programming unit [EN 746-2].
8
---------------------- Page: 10 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
3.18
flame trap
a device capable of arresting a flame while allowing the passage of gas
3.19
start-up interlock
the safety shut-down condition of the control system such that re-start cannot be accomplished without
manual re-set.
3.20
multiturn valve
a valve which, in order to operate from the fully closed to the fully open position, requires a number of
revolutions of the operating key or handwheel to be completed.
3.21
non-return valve
a device to prevent the reversal of flow of air, fuel, oxygen etc. [746-2].
3.22
pilot flame
pilot burner flame that is used to ignite the main flame [EN 746-2].
3.23
interrupted pilot
a pilot which is ignited each time the burner is started up and which is extinguished at the end of the main
flame establishment period.
3.24
pilot shrinkage
unintended reduction in the length of the pilot flame.
3.25
safe start check
a means of providing safety shut-down or start-up interlock on start-up if a fault or flame simulating condition is
present.
3.26
safe shut-down
the shutting off of all reaction gas and reaction air supplies to the atmosphere generator.
NOTE 1 This can be accomplished either manually or automatically
NOTE 2 This should not be confused with system of safety shut-down (see 3.27).
3.27
system of safety shut-down
a system that provides the automatic shutting off of all gas and ignition energy.
3.28
safety shut-off valve system
a system of valves with associated circuits which enables the supply of gas to be admitted or shut off.
3.29
slam shut valve
a valve which automatically closes when it is actuated by an increase in the downstream line pressure above
a set limit. Manual intervention is required to re-open the valve.
9
---------------------- Page: 11 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
3.30
start gas flame
a flame established at the start gas rate either at the main burner or at a separate pilot burner
4 List of hazards
The anticipated significant hazards are detailed in table 1. For ease of reference this table also indicates the
hazardous situations and corresponding preventative measures and should be used in conjunction with part 1
and 2 of EN 746 and clauses 5, 6 and 8 of this part of EN 746, as identified in the reference column.
Table 1 — List of Hazards, Hazardous Situations and Preventative Measures
1 2 3 4 5 6
Clause Hazards !!deleted Hazardous situation Preventative Measures References
!!
text""
""
1 MECHANICAL
1.1 General EN 746-1
2 ELECTRICAL
2.1 General
2.2 Thermal • Breakdown/reduction of • System design EN 746-1
radiation and
electrical insulation
5.3.2.18
• Correct placement of cables
other
• Cable damage/Short
6.5
• Protection of cables
phenomena
circuits:
• Fire fighting equipment (suitable for
Fire
electrical systems)
Electric shock
2.3 External • Corruption of control • System design EN 746-1
influences on circuits, particularly
5.3.2.18
• Protection of hardware
electrical
software systems
6.5
• Monitoring systems
equipment
• Failure of safety control:
• First aid:
Fire/Explosion
Equipment
Toxicity/Asphyxiation
Training
• Fire fighting equipment
3 THERMAL
3.1 General
3.2 Flames, EN 746-1
• Personal injuries such • System design
Explosions,
as:
EN 746-2
• Monitoring/inspection/maintenance
Radiation
Flash/radiation, burns
5
• Operator:
Dehydration
Instruction 6
Eyesight damage
Training
8.1
• deterioration of joints
• Personal protection equipment
and pipework and/or
distortion of structures:
• First aid:
Escaping of flammable
Equipment
or toxic fluids
Training
(gases/liquids)
• Safety devices in the work shop
• Ejection of parts
• Fire fighting equipment
4 HAZARDS GENERATED BY MATERIALS AND SUBSTANCES PROCESSED/ USED/ EXHAUSTED
4.1 General
(continued)
10
---------------------- Page: 12 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Table 1: (continued)
1 2 3 4 5 6
Clause Hazards !!!!deleted Hazardous situation Preventative Measures References
text""""
4.2 • Contact • Personal injuries such as: • Regulations for storage/use/disposal EN 746-1
with
Skin effects
5.3.1
• System design
harmful
Poisoning
5.3.2.1
• Monitoring/inspection/maintenance
liquids
Physiological effects
5.3.2.2
• Personal protection equipment
• Contact Respiratory/asphyxiating
effects 5.3.2.13
with or
• First aid:
inhalation
5.3.2.14
Equipment
of harmful
Training
6.7.3
gases/
• Consider:
6.8.9
vapours/fu
Permit-to-work system
mes
8.1
Gas analysing system
4.3 Contact with or • Personal injuries such as: • Regulations for storage/use/disposal 8.1.6
inhalation of
Skin effects
8.1.7
• Procedures for assembling, maintenance
dusts
Respiratory effects
and dismantling
Poisoning
• Provisions for disposal
Carcinogenic effects from
nickel-bearing dusts
5 FIRE AND EXPLOSION
5.1 General
5.2 Fire hazard • Property damage and/or EN 746-1
• System
personal injury caused by
Design
EN 746-2
flammable fluids
Safety systems
5.3
(gases/liquids)
• Fire fighting equipment
6.8
• Monitoring/inspection/maintenance
8.1
• Operator
Instruction
Training
• Plant housekeeping procedures
• First aid:
Equipment
Training
5.3 Explosion 5
• Property damage and/or • System
hazard personal injury caused by
Design
6
flammable fluids
Safety systems
8.1
(gases/liquids)
• Fire fighting equipment
• Monitoring/inspection/maintenance
• Operator
Instruction
Training
• Explosion relief devices
(continued)
11
---------------------- Page: 13 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Table 1: (continued)
1 2 3 4 5 6
Clause Hazards !!deleted Hazardous situation Preventative Measures References
!!
text""
""
6 HAZARDS GENERATED BY FAILURE OF SERVICES
EN 746-1
6.1 Failure of • Failure of normal control • System
energy supply:
EN 746-2
Design
• Damage to property and
Safety systems 5.2.4
• Electrical personnel
supplies
• Inert gas supply 5.3.2.17
• Control fluid 5.3.2.18
• Failure mode system
supplies
6.3.4.2
• Operator
• Cooling 6.5
Instruction
system
6.6
Training
supplies
6.8.1
• Service/repair management
6.8.9
• Consider:
8.1
Standby energy system
6.2 Failure of • Formation of explosion • Automatic inert gas purging 5.2.4
atmosphere gas/air mixtures in
5.2.5
• Standby supply of atmosphere gas
gas supply
industrial
8.1
• Failure mode system
thermoprocessing plant
• Operator
Instruction
Training
• Service/repair management
6.3 Failure of 6.1.5
• Breakdown of • Safe shut-down procedure
supplies for atmosphere gas supply
6.1.6
• Automatic inert gas purging
atmosphere
6.2
• Generating plant/failure
• Failure mode system
gas generators
of normal control
6.3
• Service/repair management
6.4
8.1
7 HAZARDS GENERATED BY FUNCTIONAL DISORDERS, MISSING OR INCORRECTLY POSITIONED/ SET SAFETY
DEVICES
EN 746-1
7.1 Unexpected
• Unexpected escape of • Avoidance of/ protection from uncontrolled
escape of fluids
high temperature gases draught effects
5.1
through furnace
5.2.3
• Precautions during maintenance
openings
5.3.2.1
• Protective devices
• Flashes of burning
5.3.2.12
gases
5.3.2.13
5.3.2.14
5.3.2.15
5.3.2.16
5.3.2.17
7.2 Failure/disorder • Unexpected start-up • System design 5
of control
6
• Unexpected overrun • Safety shut-down procedure
systems
8.1
• Inspection/maintenance
• Operator
Instruction
Training
(continued)
12
---------------------- Page: 14 ----------------------
SIST EN 746-3:2000+A1:2009
EN 746-3:1997+A1:2009 (E)
Table 1: (continued)
1 2 3 4 5 6
Clause Hazards !!deleted Hazardous situation Preventative Measures References
!!
text""
""
5
7.3 Errors of fitting
• Damage to property • System design
and/or personal injuries 6
• Marking/identification of components
8.1
• Supplier information/components
8.2
• Spare parts maintenance management
• Instruction for maintenance
• Consider:
PERMIT-TO-WORK system
7.4 Loading and EN 746-1
• Personal injuries such • System design
unloading
as:
5.1
• Sequence logic
means for
Burns
5.2.7
• Personal protection
workpieces
Poisoning
being 5.3.2.16
• Inspection/maintenance
• Damage to property
processed
8.1
caused by:
• Operator:
Overheating Instruction
Incorrect purging Training
Fire
7.5 5.2
• Pressure or • Incorrect atmosphere • System design
flow control gas production or use,
5.2.6
• Monitor/inspection/maintenance
devices resulting in:
5.3.2.7
• Operator:
Fire/explosion
• Low or high
Instruction 6.1.1
Poisoning
temperature
Training
6.8
detectors
• Explosion relief devices
• Fire fighting equipment
• First aid:
Equipment
Training
• Consider:
Gas analysing system
7.6 E
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.