PIETRO FIORENTINI VS/AM 58 User manual

VS/AM 58
EN
Relief valve
USE, MAINTENANCE
AND WARNING
MANUAL
Revision A - Edition 05/2023

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1 - INTRODUCTION
FOREWORD
All rights reserved. No part of this publication may be reproduced, distributed, translated into other languages or trans-
mitted by any electronic or mechanical media, including photocopies, recording or any other storage and retrieval system,
for any other purposes that are not exclusively the personal use of the buyer, without the express written permission of
the Manufacturer.
The manufacturer is in no way responsible for the consequences of operations carried out in a manner not in accordance
with the manual.
GENERAL REMARKS
All operating, maintenance instructions and recommendations described in this manual must be followed to in order to:
• get the best possible performance from the device;
• maintain the device in an efcient condition;
• carry out maintenance work regularly.
Training the personnel in charge is essential in order to:
• the use and maintenance of the device in the correct manner;
• correctly apply the safety alerts and recommended procedures.
Revision: A
COPYRIGHT 2023
© PIETRO FIORENTINI S.P.A.

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1.1 - REVISION HISTORY
Revision
index Date Revision contents
A05/2023 First issue
Tab. 1.1.

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INDICE
1 - INTRODUCTION .................................................................................................................. 3
1.1 - REVISION HISTORY.................................................................................................................................. 5
2 - GENERAL INFORMATION .................................................................................................. 9
2.1 - MANUFACTURER IDENTIFICATION .......................................................................................................... 9
2.2 - IDENTIFICATION OF THE PRODUCT ........................................................................................................ 9
2.3 - REGULATORY FRAMEWORK................................................................................................................... 9
2.4 - WARRANTY............................................................................................................................................ 10
2.5 - SYMBOLS USED IN THE MANUAL......................................................................................................... 10
2.6 - ADDRESSEES, SUPPLY AND STORAGE OF THE MANUAL................................................................... 11
2.7 - LANGUAGE ............................................................................................................................................ 11
2.8 - APPLIED RATING PLATES...................................................................................................................... 12
2.8.1 - GLOSSARY FOR RATING PLATES........................................................................................................13
2.9 - GLOSSARY OF MEASUREMENT UNITS................................................................................................. 13
2.10 -QUALIFIED PROFESSIONAL FIGURES................................................................................................... 14
3 - SAFETY .............................................................................................................................. 15
3.1 - GENERAL SAFETY WARNINGS.............................................................................................................. 15
3.2 - PERSONAL PROTECTIVE EQUIPMENT.................................................................................................. 16
3.3 - RESIDUAL RISKS ................................................................................................................................... 17
3.3.1 - TABLE SHOWING RESIDUAL RISKS DUE TO PRESSURE ...................................................................18
3.3.2 - TABLE OF RESIDUAL RISKS FOR POTENTIALLY EXPLOSIVE ATMOSPHERES ...................................20
3.4 - OBLIGATIONS AND PROHIBITIONS ....................................................................................................... 22
3.5 - SAFETY PICTOGRAMS .......................................................................................................................... 22
3.6 - NOISE LEVEL ......................................................................................................................................... 22
4 - DESCRIPTION AND OPERATION .................................................................................... 23
4.1 - GENERAL DESCRIPTION ....................................................................................................................... 23
4.2 - OPERATION............................................................................................................................................ 24
4.3 - INTENDED USE ...................................................................................................................................... 25
4.3.1 - ENVISAGED USE ..................................................................................................................................25
4.3.2 - REASONABLY FORESEEABLE MISUSE ...............................................................................................25
4.3.3 - TYPES OF FLUIDS ................................................................................................................................25
4.4 - TECHNICAL FEATURES/PERFORMANCE .............................................................................................. 26

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5 - TRANSPORT AND HANDLING......................................................................................... 27
5.1 - SPECIFIC WARNINGS FOR TRANSPORT AND HANDLING ................................................................... 27
5.1.1 - PACKAGING AND FASTENERS USED FOR TRANSPORT ....................................................................28
5.2 - PACKAGING CONTENT.......................................................................................................................... 28
5.3 - PHYSICAL CHARACTERISTICS OF THE DEVICE ................................................................................... 29
5.3.1 - STANDARD VERSION ...........................................................................................................................29
5.3.2 - FLANGED VERSION .............................................................................................................................30
5.4 - DEVICE ANCHORING AND LIFTING METHOD ....................................................................................... 31
5.4.1 - FORKLIFT HANDLING METHOD...........................................................................................................32
5.5 - PACKAGING REMOVAL.......................................................................................................................... 34
5.5.1 - PACKAGING DISPOSAL .......................................................................................................................34
5.6 - STORAGE AND ENVIRONMENTAL CONDITIONS .................................................................................. 35
5.6.1 - STORAGE LASTING LONGER THAN THE MAXIMUM TIME ALLOWED................................................35
6 - INSTALLATION .................................................................................................................. 36
6.1 - INSTALLATION PRE-REQUISITES........................................................................................................... 36
6.1.1 - ALLOWED ENVIRONMENTAL CONDITIONS.........................................................................................36
6.1.2 - STORAGE LASTING LONGER THAN THE MAXIMUM TIME ALLOWED................................................36
6.1.3 - CHECKS BEFORE INSTALLATION........................................................................................................37
6.2 - SPECIFIC SAFETY INSTRUCTIONS FOR THE INSTALLATION STEP...................................................... 38
6.3 - POSSIBLE INSTALLATIONS OF THE DEVICE ......................................................................................... 39
6.4 - INSTALLATION PROCEDURE ................................................................................................................. 40
6.4.1 - DEVICE INSTALLATION PROCEDURE ..................................................................................................41
6.5 - POST-INSTALLATION CHECKS .............................................................................................................. 41
7 - COMMISSIONING/MAINTENANCE EQUIPMENT........................................................... 42
7.1 - LIST OF EQUIPMENT.............................................................................................................................. 42
8 - COMMISSIONING ............................................................................................................. 43
8.1 - GENERAL WARNINGS ........................................................................................................................... 43
8.1.1 - SAFETY REQUIREMENTS FOR COMMISSIONING ...............................................................................43
8.2 - PRELIMINARY PROCEDURES FOR COMMISSIONING .......................................................................... 44
8.3 - PROPER COMMISSIONING CHECK ...................................................................................................... 45
8.4 - CALIBRATION OF EQUIPMENT AND ACCESSORIES INSTALLED.......................................................... 45
8.5 - RELIEF VALVE COMMISSIONING PROCEDURE VS/AM 58.................................................................... 46
8.5.1 - WITH EXTERNAL PRESSURE SOURCE ...............................................................................................46
8.5.2 - WITHOUT EXTERNAL PRESSURE SOURCE ........................................................................................48

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9 - MAINTENANCE AND FUNCTIONAL CHECKS................................................................ 49
9.1 - GENERAL WARNINGS ........................................................................................................................... 49
9.2 - PERIODICALLY CHECKING AND INSPECTING THE EQUIPMENT FOR PROPER OPERATION .............. 51
9.3 - ROUTINE MAINTENANCE ...................................................................................................................... 52
9.3.1 - GENERAL SAFETY WARNINGS............................................................................................................52
9.3.2 - REPLACEMENT FREQUENCY FOR COMPONENTS SUBJECT TO WEAR ...........................................52
9.4 - ROUTINE MAINTENANCE PROCEDURES.............................................................................................. 54
9.4.1 - PRELIMINARY OPERATIONS................................................................................................................54
9.4.2 - DISASSEMBLY/REASSEMBLY ..............................................................................................................54
9.4.3 - TIGHTENING TORQUES ......................................................................................................................56
9.4.3.1 - TIGHTENING TORQUES FOR PRESSURE SWITCHES MODELS 102M/102MH - 105M/105MH .56
9.4.4 - REPLACING ELEMENTS SUBJECT TO WEAR AND ABRASION...........................................................59
9.4.5 - RELIEF VALVE MAINTENANCE PROCEDURE VS/AM 58......................................................................60
9.4.6 - PROCEDURE FOR RECOMMISSIONING AFTER MAINTENANCE ........................................................66
10 - TROUBLESHOOTING........................................................................................................ 67
10.1 -GENERAL WARNINGS ........................................................................................................................... 67
10.2 -OPERATOR QUALIFICATION SPECIFICATION........................................................................................ 68
10.3 -TROUBLESHOOTING PROCEDURES .................................................................................................... 68
10.4 -TROUBLESHOOTING TABLE.................................................................................................................. 68
11 - UNINSTALLATION AND DISPOSAL ................................................................................. 69
11.1 -GENERAL SAFETY WARNINGS.............................................................................................................. 69
11.2 -QUALIFICATION OF THE OPERATORS IN CHARGE............................................................................... 69
11.3 -UNINSTALLATION................................................................................................................................... 69
11.4 -INFORMATION REQUIRED IN CASE OF RE-INSTALLATION................................................................... 70
11.5 -DISPOSAL INFORMATION...................................................................................................................... 70
12 - RECOMMENDED SPARE PARTS..................................................................................... 71
12.1 -GENERAL WARNINGS ........................................................................................................................... 71
12.2 -HOW TO REQUEST SPARE PARTS........................................................................................................ 71
13 - CALIBRATION TABLES ..................................................................................................... 73
13.1 -CALIBRATION TABLES ........................................................................................................................... 73
13.1.1 - SAFETY VALVE VERSION......................................................................................................................73
13.1.2 - RELIEF VALVE VERSION .......................................................................................................................73

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2 - GENERAL INFORMATION
2.1 - MANUFACTURER IDENTIFICATION
Manufacturer PIETRO FIORENTINI S.P.A.
Address
Via Enrico Fermi, 8/10
36057 Arcugnano (VI) - ITALY
Tel. [phone] Fax [phone]
www.orentini.com sales@orentini.com
Tab. 2.2.
NOTICE!
For any problems with the device, please contact your gas network distributor.
2.2 - IDENTIFICATION OF THE PRODUCT
Device RELIEF VALVE
Series VS/AM 58
Available models
• VS/AM 58 BP
• VS/AM 58 MP
• VS/AM 58 TR
Tab. 2.3.
2.3 - REGULATORY FRAMEWORK
PIETRO FIORENTINI S.P.A. with registered ofce in Arcugnano (Italy) - Via E. Fermi, 8/10, declares under its sole respon-
sibility that the VS/AM 58 relief valve covered by this manual, is classied as a safety accessory and is:
• compliant with the Pressure Equipment Directive 2014/68/EU (PED);
• designed, manufactured, tested and controlled in accordance with the requirements of the standards: UNI 11655:2016,
UNI EN 16129:2013, UNI EN 334:2019 where applicable.
NOTICE!
For specic type approvals, see the appropriate section on the Manufacturer’s website: https://www.or-
entini.com
NOTICE!
The declaration of conformity in its original version is delivered together with the device and this manual.

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2.4 - WARRANTY
PIETRO FIORENTINI S.P.A. guarantees that the device was manufactured using the best materials, with high quality work-
manship, and complies with the quality requirements, specications and performance set out in the order.
The warranty shall be considered null and void and PIETRO FIORENTINI S.P.A. shall not be liable for any damage and/or
malfunctions:
• due to any acts or omissions of the purchaser or end-user, or any of their carriers, employees, agents, or any third
party or entity;
• in the event that the purchaser, or a third party, makes changes to the device supplied by PIETRO FIORENTINI S.P.A.
without the prior written approval of the latter;
• in the event of failure by the purchaser to comply with the instructions contained in this manual, as provided by
PIETRO FIORENTINI S.P.A.
NOTICE!
The warranty conditions are specied in the commercial contract.
2.5 - SYMBOLS USED IN THE MANUAL
Symbol Denition
Symbol used to identify important warnings for the safety of the operator and/or device.
Symbol used to identify information of particular importance in the instruction manual.
The information may also concern the safety of the personnel involved in using the device.
Obligation to consult the instruction manual.
Indicates a requirement for the personnel to refer to (and understand) the instruction manual
before working with or on the device.
Tab. 2.4.
HAZARD!
Alerts to a hazard with a high level of risk, an imminent hazardous situation which, if not prevented, will
result in death or severe damage.
WARNING!
Alerts to a hazard with a medium level of risk, a potentially hazardous situation which, if not prevented,
may result in death or severe damage.
ATTENTION!
Alerts to a hazard with a low level of risk, a potentially hazardous situation which, if not prevented, could
result in minor or moderate damage.
NOTICE!
Alerts to specic warnings, directions or notes of particular concern, that are not related to physical injury,
as well as practices for which physical injury is not likely to occur.

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2.6 - ADDRESSEES, SUPPLY AND STORAGE OF THE MANUAL
The instruction manual is intended for qualied technicians responsible for operating and managing the device throughout
its service life.
It contains the necessary information to properly use the device and keep its functional and qualitative characteristics
unchanged over time. All information and warnings for safe, correct use are also provided.
The manual, as well as the declaration of conformity and/or test certicate, is an integral part of the device and must
always accompany it whenever it is moved or resold. It is the responsibility of the qualied professionals (see paragraph
2.10) to use and manage the device.
WARNING!
Removing, rewriting or editing the pages of the manual and their contents is not allowed.
PIETRO FIORENTINI S.p.A. shall not be held liable for any damage to people, animals and property caused
by failure to adhere to the warnings and operating procedures described in this manual.
2.7 - LANGUAGE
The original instruction manual was drawn up in Italian.
Any translations into additional languages are to be made from the original instruction manual.
HAZARD!
The Manufacturer is not responsible for any incomplete translations. If any inconsistency is found, please
refer to the text of the original manual.
If inconsistencies are found or the text does not make sense:
• stop any actions;
• immediately contact PIETRO FIORENTINI S.p.A. at the addresses specied in paragraph 2.1 (“Identi-
cation of the manufacturer”).
WARNING!
PIETRO FIORENTINI S.p.A. shall be held liable for the information provided in the original manual only.

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2.8 - APPLIED RATING PLATES
WARNING!
Removing nameplates and/or replacing them with other plates is strictly not allowed.
Should the plates be unintentionally damaged or removed, the customer must notify
PIETRO FIORENTINI S.p.A.
The device is equipped with rating plate (A):
ARCUGNANO(VI) - ITALY
S.n.
DN:
Wdo: Kd:
T:
SAFETY VALVE PS:
ID n.
Flange: Fluid:
bar
Wdu:
Set press: bar
Overpress: %
Blowdown pressure: %
Fig. 2.1. Positioning of rating plate

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2.8.1 - GLOSSARY FOR RATING PLATES
The terms and abbreviations used on rating plates are described in Tab. 2.5:
Term Description
CE CE marking ensuring the conformity of the product with the requirements of the applicable EU
directives or regulations.
ID Identier of the body that issued the CE marking.
Model Device model.
PS Maximum admissible pressure that can be supported in safe conditions by the structure of the
body of the device (Bar).
Wd Calibration range of the device that can be obtained by using the setting springs indicated in
the appropriate tables.
Relief Relief valve cut-in pressure (Bar).
DN i/o Nominal diameter of device inlet/outlet connections.
SN Serial number of the device.
Fluid Type of gas that the device can be used with.
TS Device design temperature range (°C).
Wds Calibration range of the device that can be achieved using the parts and setting spring tted at
the time of testing (Bar).
AG Accuracy of device intervention.
Date Month and year of manufacture of the device.
Tab. 2.5.
2.9 - GLOSSARY OF MEASUREMENT UNITS
Type of measurement Unit of measurement Description
Volumetric ow rate
Sm³/h Standard cubic metres per hour
Sm³ Standard cubic metres
m³/h Cubic metres per hour
m³ Cubic metres
Pressure
bar Unit of measurement in the CGS system
“wc Water column inch
Pa Pascal
Temperature
°C Degree centigrade
°F Fahrenheit degree
K Kelvin
Tightening torque Nm Newton metre
Sound pressure dB Decibel
Other measures
V Volt
W Watt
F Farad
H Henry
A Ampere
ΩOhm
Tab. 2.6.

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2.10 - QUALIFIED PROFESSIONAL FIGURES
Qualied operators in charge of using and managing the device throughout its technical service life:
Professional gure Denition
Installer
Qualied operator able to:
• handle materials and equipment;
• carry out all the operations necessary to properly install the device;
• perform all the operations necessary for the proper functioning of the device and the
system in safety;
• be able to perform all the operations necessary to uninstall and subsequently dispose
of the device in compliance with the regulations in force in the country of installation.
User’s
technician /
Specialised
technician
Technician trained and authorised to use and manage the device for the activities it was
supplied for. They must:
• be able to perform all operations required for the proper functioning of the device and
the system, and for their safety and that of any third parties present;
• perform maintenance on all parts of the device subject to maintenance;
• access all device parts for visual inspection, checking equipment status, making adjust-
ments and calibrations;
• have proven experience in properly using the equipment similar to that described in this
manual, and be trained, informed and instructed in this regard.
Tab. 2.7.

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3 - SAFETY
3.1 - GENERAL SAFETY WARNINGS
WARNING!
The device described in this manual is:
• subject to pressure in pressurised systems;
• normally installed in systems carrying ammable gases (for example: natural gas).
WARNING!
If the gas used is a combustible gas, the installation area of the device is dened as a “danger zone” as
there are residual risks that potentially explosive atmospheres may be generated.
In “danger zones” and in close proximity thereto:
• there must not be any effective sources of ignition;
• no smoking.
WARNING!
• It is strictly forbidden to repair or make any modications to the device.
• For information and warnings concerning the maintenance of the device, please refer to Chapter 9 of
this manual.
ATTENTION!
Authorised operators must not carry out operations or services on their own initiative that do not fall with-
in their competence.
Never interfere with the device:
• while under the inuence of intoxicating substances such as alcohol;
• if you are using drugs that may slow reaction times.
NOTICE!
The employer must train and inform operators:
• on how to behave during operations;
• on the equipment to be used.
Before installation, commissioning or maintenance, operators must:
• take note of the safety regulations applicable to the place of installation they are working in;
• obtain the necessary permits to operate when required;
• wear the personal protective equipment required by the procedures described in this instruction manual:
• ensure that the required collective protective equipment and safety information are available in the area they are op-
erating in.

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3.2 - PERSONAL PROTECTIVE EQUIPMENT
Tab. 3.8 shows the Personal Protective Equipment (PPE) and its description; an obligation is associated with each symbol.
Personal protective equipment means any equipment intended to be worn by the worker in order to protect them against
one or several risks that are likely to threaten their safety or health during work.
For the operators in charge, depending on the type of work requested, the most appropriate PPE of the following will be
reported and must be used:
Symbol Meaning
Obligation to use safety or insulated gloves.
Indicates a requirement for the personnel to use safety or insulated gloves.
Obligation to use safety goggles.
Indicates a requirement for personnel to use protective goggles for eye protection.
Obligation to use safety shoes.
Indicates a requirement for the personnel to use accident-prevention safety shoes.
Obligation to use noise protection equipment.
Indicates a requirement for the personnel to use ear muffs or ear plugs to protect their hearing.
Obligation to wear protective clothing.
Indicates a requirement for the personnel to wear specic protective clothing.
Obligation to use a protective mask.
Indicates a requirement for the personnel to use respiratory masks in the event of a chemical
risk.
Obligation to use a protective helmet.
Indicates a requirement for the personnel to use protective helmets.
Obligation to wear high visibility vests.
Indicates a requirement for the personnel to use high visibility vests.
Tab. 3.8.
WARNING!
Each licensed operator is obliged to:
• take care of his/her own health and safety and that of other people in the workplace who are affected
by his/her actions or omissions, in accordance with the training, instructions and equipment provided
by the employer;
• appropriately use the PPE made available;
• immediately report to the employer, the manager or the person in charge any deciencies in the equip-
ment and devices, as well as any dangerous conditions they may become aware of.

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3.3 - RESIDUAL RISKS
WARNING!
If there are any functional faults, do not operate.
Immediately contact PIETRO FIORENTINI S.p.A. for the necessary directions.
In accordance with the requirements of PED Directive 2014/68/EU point 1.2 of Annex I, below is an assessment of the
risks associated with the device and an indication of the principles adopted for their prevention, according to the following
classication:
a) Elimination and/or reduction of the risk.
b) Application of appropriate protective measures.
c) Information to users about residual risks.

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3.3.1 - TABLE SHOWING RESIDUAL RISKS DUE TO PRESSURE
WARNING!
If there are any functional faults, do not operate. Immediately contact PIETRO FIORENTINI S.p.A. for the
necessary directions.
Risk and Hazard Event and Cause Effect and
Consequence Solution and Prevention
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
• Violent impact;
• Impact (also due
to falling, improper
handling, etc.).
• Deformation;
• Broken connections
and, if pressurised,
even burst.
a. Handling and installation with appropri-
ate devices to avoid localised stress.
b. Installation in suitable places and spac-
es with appropriate guards and packaging.
c. Information in the technical manual.
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
• Use of inappropriate
uids.
• Corrosion;
• Embrittlement;
• Explosion.
a. The user must check compliance of the
used uid with what is indicated on the in-
stallation sheet.
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
• Operation at tem-
peratures below the
minimum permissi-
ble temperature.
• Embrittlement;
• Breakage;
• Explosion.
a. Install in places where the temperature
is not below the minimum permissible
temperature and/or insulate the device ad-
equately.
b. The minimum temperature allowed is in-
dicated on the data plate.
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
Explosion.
• Overpressure or
exceedance of the
rated limit values
(maximum pressure
allowed)
• Explosion;
• Breaks;
• Cracks;
• Permanent defor-
mations.
a. The device has appropriate design safe-
ty margins.
b. The user must check the maximum
pressure applicable to the equipment.
c. The maximum allowable pressure is
highlighted on the appropriate plate on the
device.
Pressurised uid
leakage.
Projection of
metallic and
non-pressurised
parts.
• Incorrect attach-
ment of the device.
• Deformation;
• Breakage.
The device is equipped with unied type
process connections and compression t-
tings.
b. The installer must ensure correct xing
to the line.
c. Indications in the technical manual.
Explosion
of the appliance
pressurised uid
leakage.
Projection of me-
tallic parts.
• Operation at tem-
peratures above the
maximum permissi-
ble temperature.
• Reduction of me-
chanical resistance
and breakage of the
device;
• Explosion.
a. The commissioning technician must
equip the system with suitable control and
safety devices.
b. The maximum permissible temperature
is indicated on the installation sheet.
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
• Electrostatic poten-
tial differential stray
currents.
• Corrosion localised
in the device.
b. The commissioning technician must
equip the device with the necessary means
of protection and earthing if indicated on
the installation sheet.
c. The above requirements are indicated in
the technical manual.

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Risk and Hazard Event and Cause Effect and
Consequence Solution and Prevention
Pressurised gas
leak.
Projection of
metallic and
non-pressurised
parts.
• Humidity;
• Environments with
aggressive atmos-
phere.
• Deterioration of
external surfaces;
• Corrosion.
a. The user must shut off the line and con-
tact PIETRO FIORENTINI S.p.A.
Tab. 3.9.

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3.3.2 - TABLE OF RESIDUAL RISKS FOR POTENTIALLY EXPLOSIVE ATMOSPHERES
Tab. 3.10 shows the conditions that can lead to the generation of a potentially explosive atmosphere respectively for:
• the pressure regulator;
• the monitor;
• the slam-shut device.
The table is valid for use with natural gas with a density of no more than 0.8; for different densities, the installation and
environmental conditions must also be evaluated.
WARNING!
If the gas used is a combustible gas, the installation area of the device is dened as a “danger zone” as
there are residual risks that potentially explosive atmospheres may be generated.
There must be no effective sources of ignition in “danger zones” and in close proximity thereto.
Operating
conditions
Potentially
explosive
atmosphere
Normative references
Management measures in-
cluded in the instructions for
use and warning
First start-up No
• During the production cycle and
before the CE marking accord-
ing to Directive 2014/68/EC, the
external tightness of the device
is checked at a value of 1.1 PS,
in accordance with Standard EN
334.
• Before commissioning, the exter-
nal tightness of the portion of the
system on which the device is
installed is checked at a suitable
pressure (according to Stand-
ards EN 12186 and EN 12279).
The instructions for use indicate
the need to meet the requirements
in Standards EN 12186 and EN
12279.
Operation in
normal conditions No
The indications in the previous point
apply, in addition:
• the device is installed outdoors
or in an environment with natural
ventilation according to Stand-
ards EN 12186 and EN 12279;
• the installation is subject to sur-
veillance according to current
national rules/good practice/the
device manufacturer’s instruc-
tions (in accordance with the
provisions of Standard EN 12186
and Standard EN 12279).
The instructions for use indicate
that:
• any environment in which the
device is installed must meet
the requirement of Standards
EN 12186 and EN 12279;
• periodic checks and main-
tenance must be carried out
during surveillance in accord-
ance with the national rules
in force (if any), and with the
specic manufacturer’s rec-
ommendations.
Breakage of the
control head dia-
phragm
(malfunction)
No
This event must be considered a rare
malfunction.
All atmospheric pressure chambers
delimited on at least one side by a
diaphragm must be channelled to
a safe area (in accordance with the
provisions of Standard EN 12186 and
Standard EN 12279).
The instructions for use indicate
the need to meet the requirements
of Standards EN 12186 and EN
12279.