Aerospace series - Handheld fire extinguishers with synthesis gases, for aircraft use - Technical specification and qualification conditions

This standard specifies the technical requirements and qualification conditions for handheld fire extinguishers made with metal vessels and using synthesis gases for aircraft use, designed for use in the cockpit, in the passenger cabin and to protect areas accessible to the crew.

Luft- und Raumfahrt - An Bord Handfeuerlöscher - Lieferbedingungen und Qualifikationsbedingungen

Série aérospatiale - Extincteurs portatifs pour aéronefs aux agents gazeux de synthèse - Spécification technique et conditions de qualification

Aeronavtika - Ročni gasilniki s sintetičnimi plini za uporabo v aeronavtiki - Tehnična specifikacija in kvalifikacijski pogoji

General Information

Status
Published
Publication Date
17-Mar-2009
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
10-Mar-2009
Due Date
15-May-2009
Completion Date
18-Mar-2009

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EN 4649:2009
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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Luft- und Raumfahrt - An Bord Handfeuerlöscher - Lieferbedingungen und QualifikationsbedingungenSérie aérospatiale - Extincteurs portatifs pour aéronefs aux agents gazeux de synthèse - Spécification technique et conditions de qualificationAerospace series - Handheld fire extinguishers with synthesis gases, for aircraft use - Technical specification and qualification conditions49.095Oprema za potnike in oprema kabinPassenger and cabin equipment13.220.10Gašenje požaraFire-fightingICS:Ta slovenski standard je istoveten z:EN 4649:2009SIST EN 4649:2009en01-maj-2009SIST EN 4649:2009SLOVENSKI
STANDARD



SIST EN 4649:2009



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 4649February 2009ICS 13.220.10; 49.095 English VersionAerospace series - Handheld fire extinguishers with synthesisgases, for aircraft use - Technical specification and qualificationconditionsSérie aérospatiale - Extincteurs portatifs pour aéronefs auxagents gazeux de synthèse - Spécification technique etconditions de qualificationLuft- und Raumfahrt - An Bord Handfeuerlöscher -Lieferbedingungen und QualifikationsbedingungenThis European Standard was approved by CEN on 5 October 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial 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 STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre:
Avenue Marnix 17,
B-1000 Brussels© 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 4649:2009: ESIST EN 4649:2009



EN 4649:2009 (E) 2 Contents Page Foreword . 3Introduction . 41Scope . 52Normative references . 53Terms and definitions . 54Symbols and abbreviations . 65Description . 66Design . 77Characteristics . 88Qualification tests . 129Manufacturing requirements . 2310Marking . 2611Maintenance . 2812Quality assurance . 2813Qualification . 2814Traceability . 2915Packaging . 2916Storage . 2917Recovery and recycling . 29Annex A (normative)
Pressure and temperature diagram . 30Annex B (normative)
Dielectric test diagram . 31Annex C (normative)
Technical index . 33Annex D (normative)
Qualification tests . 34 SIST EN 4649:2009



EN 4649:2009 (E) 3 Foreword This document (EN 4649:2009) has been prepared by the Aerospace and Defence Industries Association of Europe - Standardization (ASD-STAN). After enquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the member countries of ASD, prior to its presentation to CEN. 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 August 2009, and conflicting national standards shall be withdrawn at the latest by August 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. 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 the United Kingdom.
SIST EN 4649:2009



EN 4649:2009 (E) 4 Introduction This standard is implemented to define aeronautical requirements regarding the following:
 all handheld fire extinguishers using synthesis gases;  all aircraft;  the need to protect persons, equipment and the environment (in particular the provisions concerning implementation of the Montreal protocol). If the extinguisher uses a synthesis gas under the terms of a waiver to current legislation, all the tests except the extinguishing efficiency tests, shall be run using an authorised equivalent substitute agent.
This standard is intended for fire extinguishers with a maximum operating pressure up to 25 bars. SIST EN 4649:2009



EN 4649:2009 (E) 5 1 Scope This standard specifies the technical requirements and qualification conditions for handheld fire extinguishers made with metal vessels and using synthesis gases for aircraft use, designed for use in the cockpit, in the passenger cabin and to protect areas accessible to the crew. 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 9100, Aerospace series — Quality management systems — Requirements (based on ISO 9001:2000) and Quality systems — Model for quality assurance in design, development, production, installation and servicing (based on ISO 9001:1994) EN 9103, Aerospace series — Quality management systems — Variation management of key characteristics EN 9133, Aerospace series — Quality management systems — Qualification procedure for aerospace standard parts EN 10002-1, Metallic materials — Tensile testing — Part 1: Method of test at ambient temperature EN 10204, Metallic products —Types of inspection documents ISO 3941, Classification of fires ISO 7165, Fire fighting — Portable fire extinguishers — Performance and construction DOT/FAA/AR-01-37, Development of a minimum performance standard for hand-held fire extinguishers as a replacement for Hamon 1211 on Civilian Transport Category Aircraft 1 ED-14D/RTCA/DO-160, Environmental conditions and test procedures for airborne equipment 2 EASA – Part 145, Maintenance Organisation Approvals 3 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 pressure-relief safety device device which releases the pressure inside the vessel in the event of over-pressure 3.2 handheld fire extinguisher
extinguisher designed to be carried and used by hand, weighing 20 kg or less 3.3 bracket element used to hold the extinguisher on board
1 Published by: Office of Aviation Research – Washington, D.C. 20591. 2 Published by: EUROCAE, 102 rue Etienne Dolet – 92240 Malakoff. 3 Published by: European Aviation Safety Agency – Postfach 10 12 53 – D-50452 Koeln, Germany. SIST EN 4649:2009



EN 4649:2009 (E) 6 3.4 survival temperature temperature to which the extinguisher may be exposed without compromising subsequent use in the operating temperature range 3.5 fire classes according to ISO 3941, the following fire classes may be identified:  class A: these are fires of solid materials, generally organic in nature, the combustion of which normally leads to the formation of embers  class B: these are fires involving liquids or liquefiable solids According to this standard the following fire class is added:  class H: these are fires in indirectly accessible spaces (hidden fires)
4 Symbols and abbreviations bar Unit of pressure, 1 bar is equal to 0,1 MPa IF Inspection File
DF Definition File MF Manufacturing File P (T max.) Pressure at maximum operating temperature P (T min.) Pressure at minimum operating temperature TP Test Pressure TS Technical Specification T max. Maximum operating temperature T min. Minimum operating temperature V Internal volume of the vessel 5 Description A handheld fire extinguisher consists of, but is not limited to:  a vessel;  an extinguishing agent;
 a pressurisation agent if necessary (acting as the propellant);  a pressure indicating device;  a pick-up device;  a controlling device;  a projection device;  a discharge hose if necessary;  a pressure-relief safety device;  a controlling device locking system;  an indicator of not used. NOTE The bracket is independent of the extinguisher, but shall be qualified jointly with it. SIST EN 4649:2009



EN 4649:2009 (E) 7 6 Design 6.1 General The fire extinguisher shall operate in vertical position with the actuating device on the top.
No part shall easily be removable from the fire extinguisher and its bracket except the controlling device locking system. The design of handheld fire extinguishers shall enable them to withstand the environmental conditions specific to the aeronautical field, as defined in Clause 8:  mechanical (vibrations, crash resistance, operational shocks);  climatic (temperature, altitude, humidity, salt mist);  electromagnetic, if applicable. 6.2 Materials The materials used to manufacture the fire extinguisher shall comply with the standards in force, shall be resistant to the extinguishing and pressurising agents and shall withstand the environmental and operating conditions. For this purpose, the designer shall determine the appropriate materials, heat treatments and protections. Magnesium alloys are prohibited. 6.3 Vessel The manufacturer shall obtain and record the analysis and testing certificates for the materials used to manufacture the vessels. The inspection documents shall provide the composition of the material and results of the chemical analysis and the results of the mechanical tests in accordance with EN 10204. The vessel shall be made of metal and its design shall comply with the requirements of 7.2. If a material other than metal is used, the manufacturer must show evidence that this material is compliant to the requirements set forth in this standard. Dedicated test procedures for this material must be developed by the supplier. 6.4 Extinguishing and pressurising agents The products used shall comply with the applicable standards and regulations in force. 6.5 Pressure-relief safety device The fire extinguisher may be equipped with a pressure-relief safety device designed to protect the pressurised elements against over-pressure. The operation of this device shall be based on the pressure rise principle. The design of this device shall comply with the requirements of 7.3.1. This device may also be used as a filling device. If not fitted with a pressure-relief safety device, the fire extinguisher shall be designed to automatically evacuate its entire contents safely, in case of over pressure. In this case, the provisions of 7.3.2 shall apply. SIST EN 4649:2009



EN 4649:2009 (E) 8 6.6 Pressure indicating device The handheld fire extinguisher shall be equipped with a device indicating that the pressure of the fire extinguisher is within operating limits. 6.7 Pick-up device This device shall allow an efficient pick-up of the extinguishing agent.
6.8 Projection device This device shall allow efficient and easy projection of the extinguishing agent onto the fire. 6.9 Controlling device This device shall be used to start and stop the flow of extinguishing agent. 6.10 Discharge hose The fire extinguishers with more than 2 kg of agent(s) shall be equipped with a hose. 6.11 Controlling-device locking system This device is designed to prevent inadvertent actuation. 6.12 Indicator of not used This device shall show whether the fire extinguisher has been operated. This may be in the form of a wire and seal or a mechanism that prevents re-insertion of the safety device. 6.13 Bracket
This device is used to hold the fire extinguisher on board. The fire extinguisher shall be easily removable from its bracket and the related operating method shall be obvious and non-ambiguous. 7 Characteristics 7.1 General All pressure shall be in accordance with Annex A. The pressure levels reached in the vessel shall be determined according to the agent(s) used, the filling coefficient, the pressurisation pressure, the maximum survival temperature. The minimum range of operating temperature is − 40 °C to 70 °C. The minimum range of survival temperature is − 55 °C to 85 °C. An attachment of elements on the vessel shall not weaken its mechanical strength. SIST EN 4649:2009



EN 4649:2009 (E) 9 7.2 Vessel 7.2.1 Thickness of the wall The thickness of the wall shall be such that regardless of the extinguishing agent used and its vapour pressure, the 0,2 % offset yield strength of the material chosen shall never be exceeded at the vessel test pressure. If markings are etched, these shall be done in a dedicated area. 7.2.2 Mechanical properties The ratio shall be:
mp0.2RR≤ 0,90 where Rp0.2 is the yield strength, see EN 10002-1; Rm is the tensile strength, see EN 10002-1. 7.2.3 Test pressure The test pressure shall be minimum equal to 125 % of the pressure corresponding to the maximum survival temperature. 7.2.4 Burst pressure The burst pressure shall be minimum equal to 270 % of the pressure corresponding to the maximum survival temperature. 7.3 Safety in case of over-pressure 7.3.1 Pressure-relief safety device Pressure levels for activation of the pressure relief safety device shall be:  minimum: pressure equivalent to 105 % of the pressure at maximum survival temperature,  maximum: pressure equivalent to the test pressure (7.2.3). 7.3.2 Fire extinguisher without a pressure-relief safety device In case of over pressure, no mechanical element shall be ejected from the fire extinguisher and the fire extinguisher shall remain in its bracket. 7.4 Pressure indicating device The reading range of the pressure indicating device shall comprise (see Figure 1):  a zero reference (to indicate zero pressure). If there is a needle stop, it shall be below the zero reference.  a green zone (4) corresponding to the pressures of the whole operating temperature range in accordance with Figure 1. SIST EN 4649:2009



EN 4649:2009 (E) 10
Key 1 Stop 2 Red 3 Rounded-off to 0,5 bar 4 Green P(T min.)
Pressure at minimum operating temperature
P(T max.)
Pressure at maximum operating temperature
Figure 1 The pressures are rounded off to the nearest half-bar or bar. The zones located on either side of the green zone are red. To ensure that the pressure indication is readable, the characteristics shall be as follows:  the needle movement across the pressure zone shall allow a clear reading;  a mark shall show the pressure at the temperature of 20 °C. NOTE An indicating device giving the same indications as mentioned above is also acceptable. 7.5 Pick-up device The pick-up device (e.g. plunger tube) shall allow drainage of at least 90 % of the extinguishing agent during the test defined in 8.4.1. 7.6 Controlling device The characteristics of the controlling device are as follows:  actuation of the controlling device shall, within 2 s, start emission of the extinguishing agent stream and shall stop it as soon as the controlling device is released;  tightness shall be ensured between two emissions to comply with 8.4.4;  it shall be actuated with one hand only applying a maximum strength of 10 daN. 7.7 Controlling-device locking system The characteristics of the controlling-device locking system are as follows: SIST EN 4649:2009



EN 4649:2009 (E) 11  it shall be unlocked with a strength between 2 daN to 10 daN;  it shall withstand a strength of 20 daN applied to the controlling device without damage and shall remain removable after release of the force. 7.8 Indicator of not used When activated, it shall not be possible to restore the indicator in its initial condition without intervention of qualified operator with appropriate tool.
If the controlling device is operated, the status of indicator of not used shall change. 7.9 Projection device  It shall allow an efficient projection of extinguishing agent onto the fire.  It shall create a visible stream to allow the user to orientate it onto the fire. 7.10 Discharge hose 7.10.1 Hose – sizing  fire extinguishers with more than 2 kg of agent(s) shall be equipped with a hose of minimum length 400 millimetres;  if the fire extinguishers with 2 kg or less of agent(s) are equipped with a hose, the minimum length of this hose shall be 250 millimetres. 7.10.2 Hose – mechanical strength The hose attached to the fire extinguisher and all its connections shall withstand a pull strength equivalent to twice the mass of the full fire extinguisher without damage. 7.10.3 Hose – pressure strength The hose burst pressure shall be at least three times the maximum-operating temperature pressure, with the test run at ambient temperature.
7.11 Discharge duration The discharge duration shall be in accordance with ISO 7165. The discharge duration is taken to mean the time for which extinguishing agent is discharged without interruption, with the valve fully opened. The emission of any propellant gas is not considered here. The discharge duration at T min. and T max. shall not exceed the average discharge duration measured at ambient temperature by more than 50 %. 7.12 Bracket The bracket shall withstand shocks and vibration of the bracket plus fire extinguisher assembly. NOTE The bracket may be used to prevent inadvertent actuation of the fire extinguisher control system. SIST EN 4649:2009



EN 4649:2009 (E) 12 7.13 Fire extinguisher tightness Leakage shall be limited to:  1 cc of gas per day and per kilogram of extinguisher charge or 1 cc of gas per day and per litre of extinguisher charge;
 loss of charge mass not exceeding 5 % per year. 7.14 Visual access When the fire extinguisher is installed on its bracket, the following points shall be visible:  code symbols of fire classes;
 pressure indicating device;  controlling-device locking system has not been unlocked. 8 Qualification tests 8.1 General test conditions and definition 8.1.1 Application of qualification The qualification procedure requires:  transmission of the qualification application to the competent authorities in accordance with applicable regulations;  the technical documentation defining the equipment, including justification of the pressure strength through the calculation note or experimental design method;  the technical user's guide;  the technical data sheet in accordance with the specimen in Annex C. 8.1.2 Equipment for qualification A minimum of 21 fire extinguishers with brackets to be qualified shall be submitted in operating condition. See Annex D. If not already qualified in accordance with this standard, the following components shall be submitted for qualification purpose:  vessel: 5 units for each test. See 8.3.  pressure indicating device: 5 units. See 8.4.3.  pressure-relief safety device: 10 units where applicable. See 8.4.2.  discharge hose: 5 units where applicable. See 8.4.6. 8.1.3 General test conditions Unless otherwise specified, the tests shall be performed in the following ambient conditions:  temperature: between 15 °C and 25 °C;  atmospheric pressure: between 86 kPa and 106 kPa;  relative humidity: less than 85 %. SIST EN 4649:2009



EN 4649:2009 (E) 13 The equipment shall be in a stabilized condition before beginning of each test. 8.1.4 Test chronology The summary table of extinguisher’s qualification tests is given in Annex D. All the fire extinguishers that have undergone qualification shall not be used after qualification. 8.1.5 General check Each test shall be preceded and followed by a visual inspection and a check of the mass of the fire extinguisher. 8.2 Weighing The following masses shall be mentioned in the technical data sheet, see Annex C:  empty fire extinguisher;  full fire extinguisher in operating condition;  bracket. NOTE For weighing, the empty or full fire extinguisher is considered without the bracket and without protection elements used for transport and storage. 8.3 Tests on the vessel 8.3.1 Pressure test An internal pressure will be applied to the vessel. All the orifices shall be blanked using appropriate plugs. The pressure rise shall be slow and gradual, with a maximum average gradient of 2 bars per second. A stabilized internal pressure shall be applied for 30 s minimum, equal to the test pressure defined in 7.2.3. The assembly shall remain tight and shall show no defect. After releasing the pressure and stabilization of 30 s minimum, check that the volume has not increased by more than 1 % over the initial volume and that there is no damage to the material such as fractures or cracks. 8.3.2 Crush test 8.3.2.1 General Mandrel(s) is(are) positioned as shown in Figures 2 to 5 in order to minimise the risk of damaging the coupling port used to pressurise the vessel. If necessary, any other means for pressurising the vessel may be used. The length of the vessel is the maximum distance between the ends of the pressure envelope excluding all skirt and couplings. 8.3.2.2 Long vessels The following method is applied to a vessel with a length of more than 1,5 times the outside diameter. The vessel shall be installed on a non-shrinking surface and it shall be crushed by a non-shrinking block (mandrel) of radius R = (D/2 ± 10) mm with a length such that it sticks out of both sides of the crushed vessel.
SIST EN 4649:2009



EN 4649:2009 (E) 14 Vessels without welding Crushing shall be performed perpendicularly to the longitudinal axis and in the middle of the length of the vessel (see Figure 2). Front view D/10DBRBDD/10DBRBDBRBDD Top view ==90°====90° Figure 2 Crushing is performed until the distance between the block and the non-shrinking surface is within (10 ± 1) % of its external diameter D. The duration of the crushing is between 30 s and 60 s. Vessels with a longitudinal welding(s) The welding(s) shall be located in accordance with Figure 3. Crushing shall be performed perpendicularly to the longitudinal axis and in the middle of the length of the vessel. SIST EN 4649:2009



EN 4649:2009 (E) 15
Figure 3
Vessels with a transverse welding Crushing shall be performed at an angle of 45° with the longitudinal axis and in the middle of the length of the vessel (see Figure 4). SIST EN 4649:2009



EN 4649:2009 (E) 16 Front view
Top view 45°45° Figure 4
After the crush test, the vessel shall be filled with water and submitted to the pressure defined in 7.2.3. The vessel shall not have crack or leak. 8.3.2.3 Short vessels The following method is applied to vessel which length is less than or equal to 1,5 times the external diameter. Short vessels without welding A vessel is crushed perpendicularly to the approximate centre of its longitudinal axis by two non-shrinking blocks 25 mm wide, with a half-cylinder radius of R = 12,5 mm and a length such that they stick out both sides of the crushed vessel (see Figure 5). SIST EN 4649:2009



EN 4649:2009 (E) 17
Figure 5
Crushing is performed until the distance between blocks is within D/3 ± 1 % D as shown in Figure 5. The duration of the crushing is between 30 s and 60 s. For vessels with a longitudinal welding, the welding shall be located in accordance with Figure 3. For vessels with a circumferential welding or with a welding in the contact area, crushing shall take place at an angle α of between 45° and 90° to the longitudinal axis of the vessel in accordance with Figure 4. After the crush test, the vessel shall be filled with water and submitted to the pressure defined in 7.2.3. The vessel shall not have crack or leak. 8.3.3 Pressurised burst test The vessels intended for the pressurised burst test are mounted in a hydraulic device used to apply an internal rising pressure with a maximum average gradient of 2 bar/second. The burst pressure measured shall be at least 2,7 times the pressure at maximum survival temperature. All the orifices shall be blanked with appropriate plugs. The bursting test shall not cause the vessel to fragment. During the burst test, no parts shall be ejected. The tear will not originate in either a welding or in the marking. 8.3.4 Low temperature toughness test To check the impact strength of the material. Description of the test:  prepare the empty vessel at the stabilized minimum survival temperature for at least 2 h;  within the minute, install the vessel as shown on Figure 6, on a non-shrinking surface; and drop a 4 kg flat-ended cylindrical mass 75 mm in diameter placed in a guide and free-falling vertically from a height of 1 m;  let the vessel to return and stabilize at ambient temperature and then conduct the pressure test in accordance with 8.3.1. SIST EN 4649:2009



EN 4649:2009 (E) 18
Key 1 Flat-ended cylindrical mass Figure 6
8.4 Operating tests 8.4.1 Fire extinguisher 8.4.1.1 General All fire extinguishers shall operate within 2 s after the actuation of actuating device. 8.4.1.2 Discharge test at ambient temperature The following test is to be performed on 3 fire extinguishers in operating condition.  Store at ambient temperature for 12 h.  Check that the reading given by the pressure indicating device is within the green zone.  Weigh the fire extinguishers in accordance with 8.2.  Continuously discharge the fire extinguisher while measuring the discharge duration in accordance with 7.8.  Weigh again the fire extinguisher and check that the quantity of extinguishing agent discharged is in accordance with 7.5. NOTE None of the 3 discharge duration measurements shall deviate from the average value by more than 15 %. SIST EN 4649:2009



EN 4649:2009 (E) 19 8.4.1.3 Integrity test at maximum survival temperature followed by discharge at T max. The following test is to be performed on 1 fire extinguisher in operating condition. Weigh and record the mass of the extinguisher. Install it in a climatic chamber.
Increase the temperature with a gradient of about 5 °C per minute up to the maximum survival temperature. Store at this temperature for 12 h.
Gradually decrease the temperature to T max. and maintain this temperature for 12 h. Within two minutes following removal from the climatic chamber:  check that the reading given by the pressure indicating device is within the green zone;  weigh the fire extinguishers in accordance with 8.2;  continuously discharge the fire extinguisher while measuring the discharge duration in accordance with 7.8;  weigh again the fire extinguisher and check that the quantity of extinguishing agent discharged is in accordance with 7.5. 8.4.1.4 Integrity test
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