SIST EN 12921-4:2005+A1:2009
(Main)Machines for surface cleaning and pretreatment of industrial items using liquids and vapours - Part 4: Safety of machines using halogenated solvents
Machines for surface cleaning and pretreatment of industrial items using liquids and vapours - Part 4: Safety of machines using halogenated solvents
This European Standard specifies the significant hazards of machines for surface cleaning and pre-treatment - in the following called "cleaning machines" - of industrial items using halogenated solvents, either pure or as a mixture.
This European Standard applies together with EN 12921-1:2005. Both parts together cover all significant hazards relevant for cleaning machines of industrial items using liquids or vapours, when they are used as intended and under the conditions foreseen by the manufacturer (see Clause 4). The specific requirements specified in Part 4 take precedence over the respective requirements in EN 12921-1:2005.
This European Standard applies together with EN 12921-3 in case of release of flammable vapours from the cleaning liquids.
This European Standard does not apply to machinery and related equipment excluded from the scope of EN 12921-1:2005.
This European Standard is not applicable to cleaning machines which are manufactured before the publication of this European Standard by CEN.
Maschinen zur Oberflächenreinigung und -vorbehandlung von industriellen Produkten mittels Flüssigkeiten oder Dampfphasen - Teil 4: Sicherheit von Maschinen, in denen halogenierte Lösemittel verwendet werden
Dieses Dokument behandelt signifikante Gefährdungen von Maschinen zur Oberflächenreinigung und vorbehandlung — im Folgenden „Reinigungsanlagen“ genannt — von industriellen Produkten, in denen halogenierte Lösemittel (rein oder als Gemisch) verwendet werden.
Diese Europäische Norm gilt nur in Verbindung mit EN 12921-1:2005. Zusammen decken beide Teile alle signifikanten Gefährdungen für Reinigungsanlagen für industrielle Produkte, in denen Flüssigkeiten oder Dampfphasen verwendet werden, wenn sie bestimmungsgemäß und unter den vom Hersteller vorgesehenen Bedingungen verwendet werden (siehe Abschnitt 4). Die spezifischen Anforderungen in diesem Teil haben Vorrang vor vergleichbaren Vorschriften in EN 12921-1:2005.
Bei einem Freisetzen von brennbaren Dämpfen aus der Reinigungsflüssigkeit muss diese Europäische Norm zusammen mit EN 12921-3:2005 angewendet werden.
Diese Europäische Norm gilt nicht für Maschinen und deren Ausrüstung, die durch den Anwendungsbereich der EN 12921-1:2005 ausgeschlossen sind.
Diese Europäische Norm gilt nicht für Reinigungsanlagen, die vor Veröffentlichung dieser Europäischen Norm durch CEN hergestellt wurden.
Machines de nettoyage et de prétraitement de pièces industrielles utilisant des liquides ou des vapeurs - Partie 4: Sécurité des machines utilisant des solvants halogénés
La présente Norme européenne spécifie les phénomènes dangereux significatifs des machines de nettoyage et de prétraitement — ci-après désignées «machine de nettoyage» — de pièces industrielles utilisant des solvants halogénés purs ou en mélange.
La présente Norme européenne s'applique conjointement à l’EN 12921-1:2005. Les deux parties couvrent tous les phénomènes dangereux significatifs pertinents aux machines de nettoyage pour pièces industrielles utilisant des liquides ou vapeurs, lorsque ces machines sont utilisées conformément à l'usage prévu et dans les conditions prévues par le fabricant (voir Article 4). Les prescriptions spécifiques précisées dans la Partie 4 prévalent sur les prescriptions respectives de l’EN 12921-1:2005.
La présente Norme européenne s'applique conjointement à l’EN 12921-3 en cas de dégagement de vapeurs inflammables provenant de liquides de nettoyage.
La présente Norme européenne ne s'applique pas aux machines et équipements annexes exclus du domaine d'application de l’EN 12921-1:2005.
La présente Norme européenne ne s'applique pas aux machines de nettoyage de pièces industrielles fabriquées avant la date de publication de la présente Norme européenne par le CEN.
Naprave za površinsko čiščenje in predobdelavo industrijskih proizvodov s pomočjo tekočin in par - 4. del: Varnost naprav, v katerih se za čiščenje uporabljajo halogenirana topila
General Information
Relations
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.þLãþHQMHMaschinen zur Oberflächenreinigung und -vorbehandlung von industriellen Produkten mittels Flüssigkeiten oder Dampfphasen - Teil 4: Sicherheit von Maschinen, in denen halogenierte Lösemittel verwendet werdenMachines de nettoyage et de prétraitement de pièces industrielles utilisant des liquides ou des vapeurs - Partie 4: Sécurité des machines utilisant des solvants halogénésMachines for surface cleaning and pretreatment of industrial items using liquids and vapours - Part 4: Safety of machines using halogenated solvents97.080Aparati za nego talFloor treatment appliancesICS:Ta slovenski standard je istoveten z:EN 12921-4:2005+A1:2008SIST EN 12921-4:2005+A1:2009en,fr01-marec-2009SIST EN 12921-4:2005+A1:2009SLOVENSKI
STANDARDSIST EN 12921-4:20051DGRPHãþD
SIST EN 12921-4:2005+A1:2009
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 12921-4:2005+A1
November 2008 ICS 97.080 Supersedes EN 12921-4:2005 English Version
Machines for surface cleaning and pretreatment of industrial items using liquids and vapours - Part 4: Safety of machines using halogenated solvents
Machines de nettoyage et de prétraitement de pièces industrielles utilisant des liquides ou des vapeurs -Partie 4: Sécurité des machines utilisant des solvants halogénés
Maschinen zur Oberflächenreinigung und -vorbehandlung von industriellen Produkten mittels Flüssigkeiten oder Dampfphasen -Teil 4: Sicherheit von Maschinen, in denen halogenierte Lösemittel verwendet werden This European Standard was approved by CEN on 19 May 2005 and includes Amendment 1 approved by CEN on 23 October 2008.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36
B-1050 Brussels © 2008 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12921-4:2005+A1:2008: ESIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 2 Contents Page Foreword.4 Introduction.5 1 Scope.6 2 Normative references.6 3 Terms and definitions.6 4 List of significant hazards.8 5 Safety requirements and/or measures.10 5.1 General.10 5.2 Mechanical hazards.10 5.3 Safety requirements and measures against electrical hazards.11 5.4 Safety requirements and measures against thermal hazards.11 5.5 Safety requirements and measures against noise.12 5.6 Safety requirements and measures against hazards generated by materials and substances processed, used or emitted by the cleaning machine.12 5.7 Safety requirements and measures against hazard combinations.17 5.8 Safety requirements and measures against failure of energy supply.17 5.9 Safety requirements and measures against failure of control systems.18 6 Verification of the safety requirements and/or measures.18 6.1 General.18 6.2 Mechanical.18 6.3 Electrical.18 6.4 Thermal.18 6.5 Noise.18 6.6 Material and substances processed, used or emitted by the cleaning machines.18 6.7 Hazard combinations.22 6.8 Failure of energy supply.22 6.9 Control systems.22 7 Information for use.22 7.1 General.22 7.2 Instruction handbook.22 7.3 Minimum marking.24 Annex A (informative)
Examples and description of types of cleaning machines using halogenated solvents and design parameters.25 A.1 Examples and description of types of cleaning machines using halogenated solvents.25 A.2 Characteristics for halogenated solvents.30 Annex B (informative)
A-deviations.31 Annex ZA (informative)
!Relationship between this European Standard and the Essential Requirements of EU Directive 98/37/EC, amended by 98/79/EC".32 Annex ZB (informative)
!Relationship between this European Standard and the Essential Requirements of EU Directive 2006/42/EC".33 Bibliography.34
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 3
Figures Figure A.1 — Collection chamber cleaning machine using halogenated solvents – type Ia.25 Figure A.2 — Single chamber cleaning machine using halogenated solvents – type Ib.26 Figure A.3 — Enclosed open cleaning machine using halogenated solvents – type II-a.27 Figure A.4 — Open top tank.28 Figure A.5a — Freeboard zones.29 Figure A.5b — Cooling zone and safety zone.29 Figure A.5c — Refrigerated zone.29
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 4 Foreword This document (EN 12921-4:2005+A1:2008) has been prepared by the Technical Committee CEN/TC 271 "Surface treatment equipment — 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 May 2009, and conflicting national standards shall be withdrawn at the latest by December 2009. This document includes Amendment 1, approved by CEN on 2008-10-23. This document supersedes EN 12921-4:2005. The start and finish of text introduced or altered by amendment is indicated in the text by tags ! ". !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 EC Directive(s). For relationship with EC Directives, see informative Annexes ZA and ZB, which are integral parts of this document." This European Standard is part of a series of standards in the area of safety for development and construction of machines for surface cleaning and pre-treatment of industrial items using liquids or vapours. The EN 12921 series includes the following parts: Part 1: Common safety requirements; Part 2: Safety of machines using water based cleaning liquids; Part 3: Safety of machines using flammable cleaning liquids; Part 4: Safety of machines using halogenated solvents. NOTE Although a machine for surface cleaning and pre-treatment of industrial items, as an integral whole, formally does not fall under the scope of the ATEX Directive 94/9/EC, the standard is based upon a fundamental risk analysis according to this directive. 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.
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 5 Introduction This European Standard is a type C standard as stated in EN 12100. This European Standard contains additional safety requirements to and/or deviations from EN 12921-1:2005. The machinery concerned and the extent to which hazards, hazardous situations and events are covered are indicated in the scope of this European 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 the other standards, for cleaning machines that have been designed and built according to the provisions of this type C standard.
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 6
1 Scope This European Standard specifies the significant hazards of machines for surface cleaning and pre-treatment – in the following called "cleaning machines" – of industrial items using halogenated solvents, either pure or as a mixture. This European Standard applies together with EN 12921-1:2005. Both parts together cover all significant hazards relevant for cleaning machines of industrial items using liquids or vapours, when they are used as intended and under the conditions foreseen by the manufacturer (see Clause 4). The specific requirements specified in Part 4 take precedence over the respective requirements in EN 12921-1:2005. This European Standard applies together with EN 12921-3 in case of release of flammable vapours from the cleaning liquids. This European Standard does not apply to machinery and related equipment excluded from the scope of EN 12921-1:2005. This European Standard is not applicable to cleaning machines which are manufactured before the publication of this European Standard by CEN. 2 Normative references The following referenced documents are indispensable for the application of this European Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1093-3, Safety of machinery — Evaluation of the emission of airborne hazardous substances — Part 3: Emission rate of a specified pollutant — Bench test method using the real pollutant EN 12921-1:2005, Machines for surface cleaning and pretreatment of industrial items using liquids or vapours — Part 1: Common safety requirements EN 12921-3, Machines for surface cleaning and pretreatment of industrial items using liquids or vapours — Part 3: Safety of machines using flammable cleaning liquids 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 principle (ISO 12100-2:2003) 3 Terms and definitions For the purpose of this European Standard, the terms and definitions given in EN ISO 12100-1:2003, EN 12921-1:2005 and the following apply. 3.1 halogenated solvent organic solvent containing at least one halogen atom per molecule and not having a flash point as obtained by standard methods NOTE Examples for halogenated solvents are: dichloromethane (methylene chloride); HCFC 123, HCFC 141B and HCFC 225;
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 7 trichloroethylene; tetrachloroethylene (perchloroethylene). These halogenated solvents used in industry can contain a small quantity of stabilising agents (anti-acid, anti-oxidant, etc). 3.2 vapour zone space within the cleaning machine filled with saturated solvent vapour when the cleaning machine is on stand-by 3.3 freeboard zone space within type II-cleaning machines above the vapour zone and up to the rim of the tanks. The freeboard zone can be further divided into cooling zone, safety zone, refrigerated zone (see Annex A) 3.4 cooling zone space within the freeboard zone of a cleaning machine above the vapour zone and up to the upper part of the condensing cooling coil 3.5 safety zone space within the freeboard zone of a cleaning machine above the cooling zone up to the rim of the tank 3.6 refrigerated zone space within the freeboard zone of a cleaning machine where its temperature is below 0 °C measured at a distance of 150 mm or more from the refrigeration cooling coils 3.7 types of cleaning machines using halogenated solvents types of halogenated solvent cleaning machines used in this European Standard are defined below and examples shown in Annex A 3.7.1 type I - sealed system system in which there is no direct connection between any volume containing halogenated solvent and the outside environment during normal operation 3.7.1.1 type Ia - collection chamber system collection chamber system consists of a collection chamber and one or more process chambers with doors, one door sealing the collection chamber from the process chamber(s), the other from the outside environment (see Figure A.1) 3.7.1.2 type Ib - single chamber system single chamber system consists of a chamber which is used for both processing items and collecting halogenated solvent vapours for recovery (see Figure A.2) 3.7.2 type II - enclosed open system system in which there is no connection between halogenated solvent and the outside environment during normal operation including loading and unloading. This cleaning machine consists of one or more open tank(s) within an enclosure. The items are processed through the cleaning machine by means of mechanical handling device and solvent fumes are collected at the inlet and outlet points of the enclosure (see Figure A.3) 3.8 piston effect rising or escaping of vapours caused by excessive speed in relation to the volume of the item by which it is introduced into or extracted from the vapour zone SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 8 3.9 open tank tank in which there is communication between solvent and the outside environment during normal operation, including loading and unloading 4 List of significant hazards Table 1 — List of significant hazards associated with machines for surface cleaning and pre-treatment using halogenated solvents Clause/sub-clause of this European Standard Hazard Clause/sub-clause of EN 12921-1:2005 4.1 General This clause contains significant hazards, hazardous situations and events, as far as they are dealt with in this European Standard, identified by risk assessment as significant for this type of machinery using halogenated cleaning liquids and which requires action to eliminate or reduce the risk. NOTE Information on the method of risk analysis is given in EN 1050. 4.1 4.2 Mechanical hazards 4.2 4.2.1 Crushing, shearing, cutting, entanglement, drawing-in, impact 4.2.1 4.2.2 High pressure fluid ejection 4.2.2 4.2.3 Ejection of parts of the cleaning machine and/or items 4.2.3 4.2.4 Mass and stability and inadequacy of mechanical strength 4.2.4 4.2.5 Slip, trip and fall hazards 4.2.5 4.3. Electrical hazards 4.3 4.4 Thermal hazards 4.4 4.5 Hazards generated by noise 4.5
SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 9 Table 1 (continued) Clause/sub-clause of this European Standard Hazard Clause/sub-clause of EN 12921-1:20054.6 Hazards generated by materials and substances processed, used or emitted by the cleaning machine 4.6 4.6.1 General 4.6.1 4.6.2 Hazards resulting from contact with/or inhalation of dangerous liquids, gases, aerosol, fumes and dusts 4.6.2 4.6.2.1 Inhalation of dangerous vapours These hazards are related to: drag-out and idling by the cleaning machine while in operation; filling, emptying and/or cleaning the cleaning machine; damaged sealing around door leading to halogenated solvent vapour leaks; opening of doors, vent valves and automatic closures before halogenated solvent purged to a safe concentration on type I-cleaning machines; failure of vapour limiting device.
4.6.2.2 Substances generated by chemical decomposition These hazards are related to: solvent overheating due to the increased concentration of contaminants (high boiling oils, hydrocarbons, tar, etc.); over temperature by the heating system; chemical reactions between halogenated solvent and water (present on the items to be cleaned due to humidity condensation or other sources); halogenated solvent breakdown due to radiation, e.g. UV light; halogenated solvent breakdown due to high temperature from external sources (e.g. flames); halogenated solvent breakdown due to reaction caused by reactive metal fines and swarf acting as a catalyst (e.g. zinc, magnesium, aluminium).
4.6.3 Fire and explosion hazard See 4.6.3.1 and 4.6.3.2 of EN 12921-1:2005. Fire or explosion hazards are caused by presence of flammable vapours (in hazardous explosion mixtures) together with a potential ignition source. Flammable vapours can be originated from total loss of halogenated solvent and overheating of combustible contaminants. Vapours produced within the flammable region and a high energy source being present. NOTE The risk of fire or explosion is extremely low with halogenated solvents during normal operation. 4.6.3 4.7 Hazards combinations 4.7 4.8 Hazards caused by failure of energy supply 4.8 4.9 Hazards related to failure of control system 4.9 SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 10 5 Safety requirements and/or measures 5.1 General Machinery shall comply with the safety requirements and/or protective measures of this clause. In addition, the cleaning machine shall be designed according to the principles of EN ISO 12100-2 for hazards relevant but not significant which are not dealt with by this European Standard (e.g. sharp edges). The common safety requirements or measures for cleaning machines using liquids or vapours in 5.1 of EN 12921-1:2005 shall be considered. The intended use shall be determined and explained/defined in the instruction handbook and, when necessary, by other additional means (plate, sign, labelling, etc.) in accordance with and/or limited by the properties of halogenated solvents either pure or as a mixture indicated in the safety data sheet. 5.2 Mechanical hazards 5.2.1 Safeguarding of danger points 5.2.1.1 General Shall be according to 5.2.1.1 of EN 12921-1:2005. 5.2.1.2 Safety measures against crushing, shearing, cutting, entanglement, drawing-in, impact Shall be according to 5.2.1.2 of EN 12921-1:2005. 5.2.1.3 Guards and interlocks Shall be according to 5.2.1.3 of EN 12921-1:2005. 5.2.1.4 Moving parts of the cleaning machine Shall be according to 5.2.1.4 of EN 12921-1:2005. 5.2.1.5 Location of controls Shall be according to 5.2.1.5 of EN 12921-1:2005. 5.2.1.6 Prevention against the hazard from close or fall of covers, lids and doors Shall be according to 5.2.1.6 of EN 12921-1:2005. 5.2.1.7 Devices for setting-up, make-ready, cleaning and trouble-shooting during the work process Shall be according to 5.2.1.7 of EN 12921-1:2005. 5.2.2 Safety measures against high pressure fluid ejection 5.2.2.1 General Shall be according to 5.2.2.1 of EN 12921-1:2005. 5.2.2.2 Safety measures against overpressure Shall be according to 5.2.2.2 of EN 12921-1:2005. SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 11 5.2.2.3 Safety measures against rupture and corrosion of piping or joints Shall be according to 5.2.2.3 of EN 12921-1:2005. 5.2.3 Safety measures against ejection of parts of the cleaning machine and/or items Shall be according to 5.2.3 of EN 12921-1:2005. 5.2.4 Safety measures regarding mass and stability and inadequacy of mechanical strength Shall be according to 5.2.4 of EN 12921-1:2005. 5.2.4.1 Positioning of the cleaning machine Shall be according to 5.2.4.2 of EN 12921-1:2005. 5.2.4.2 Safety measures against overload Shall be according to 5.2.4.3 of EN 12921-1:2005. 5.2.4.3 Safety measures against spillage Shall be according to 5.2.4.4 of EN 12921-1:2005. 5.2.5 Safety measures against slip, trip and fall Shall be according to 5.2.5 of EN 12921-1:2005. 5.3 Safety requirements and measures against electrical hazards 5.3.1 General Shall be according to 5.3.1 of EN 12921-1:2005. 5.3.2 Safety measures against electric shock Shall be according to 5.3.2 of EN 12921-1:2005. 5.3.3 Safety measures against electromagnetic influences on electrical equipment Shall be according to 5.3.3 of EN 12921-1:2005. 5.4 Safety requirements and measures against thermal hazards 5.4.1 General Shall be according to 5.4.1 of EN 12921-1:2005. 5.4.2 Heating systems Shall be according to 5.4.2 of EN 12921-1:2005. 5.4.3 Measures against contact of the skin with hot surfaces Shall be according to 5.4.3 of EN 12921-1:2005. SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 12 5.4.4 Measures against radiation and/or convection of heat Shall be according to 5.4.4 of EN 12921-1:2005. 5.4.5 Measures against overheating of cleaning liquid Shall be according to 5.4.5 of EN 12921-1:2005. 5.5 Safety requirements and measures against noise 5.5.1 General Shall be according to 5.5.1 of EN 12921-1:2005. 5.5.2 Noise reduction at source at the design stage Shall be according to 5.5.2 of EN 12921-1:2005. 5.5.3 Noise reduction by protective measures Shall be according to 5.5.3 of EN 12921-1:2005. 5.5.4 Noise reduction by information on personal protective equipment (PPE) Shall be according to 5.5.4 of EN 12921-1:2005. 5.6 Safety requirements and measures against hazards generated by materials and substances processed, used or emitted by the cleaning machine 5.6.1 General Shall be according to 5.6.1 of EN 12921-1:2005. 5.6.2 Safety measures against contact with/or inhalation of dangerous liquids, gases, vapours, aerosols, fumes Shall be according to 5.6.2 of EN 12921-1:2005. 5.6.2.1 Prevention of inhalation of dangerous vapours 5.6.2.1.1 General In order to avoid inhalation of dangerous vapours by use of cleaning machines the following measures shall be adopted: Devices shall be fitted and/or working methods adopted to control vapour emissions (see 5.6.2.1.2 to 5.6.2.1.7); national exposure limit values shall be observed (see Annex A of EN 12921-1:2005). 5.6.2.1.2 Condenser Type Ia and Type II machine shall be fitted with a condenser able to ensure that saturated vapour level calculated by design shall be maintained below the upper limit of the cooling zone. SIST EN 12921-4:2005+A1:2009
EN 12921-4:2005+A1:2008 (E) 13 In designing the condenser there is a relationship between the cleaning machine heat input, surface area of the condenser, the initial temperature of the cooling fluid and the cooling fluid flow rate. The cleaning machine heat input may be variable and therefore change through the operating cycle. The appropriate heat input for the design of the condenser shall consider all the conditions, that is including distillation during regeneration of the contaminated halogenated solvent by distillation. For type II-cleaning machines the condenser shall be interlocked such that the coolant flow rate is maintained, after the cleaning machine heating has been shut off, for a specified period or until the halogenated solvent has cooled to a specified temperature. 5.6.2.1.3 High vapour level cut off A device (for example one or more high temperature sensors), only manually re-setable shall shut the heating system off if there is a fault in the condensing system. For type II-cleaning machines the device shall be so designed as to avoid solvent vapours escaping from the top of the system. For type I-cleaning machines the device shall be designed to avoid overpressure within the system. The sensor shall be positioned as close as possible to the vapour zone or in the most suitable position for short reaction time. Additional devices may be required depending on the characteristics of the liquid to be used (e.g.: low boiling point liquid). 5.6.2.1.4 Halogenated solvent emission control 5.6.2.1.4.1 Forced ventilation A forced ventilation system which collects exhausted vapours shall be fitted into all types of cleaning machines using halogenated solvents. This requirement even applies if the halogenated solvent is used at ambient temperature. For type I machines forced ventilation system may be omitted provided that a vapour monitoring system prevents the external door or cover opening when solvent vapour concentration in the collection chamber, or in the process chamber is above the safe level according to health and safety regulations in force. Forced ventilation system shall be fitted with a flow or pressure sensing device switching off the heating system and any other devices creating vapours or mists if the design rate is not achieved. For type Ia-cleaning machines the forced ventilation system shall be de-activated by means of interlocks, when the door between the solvent process chamber(s) and the collection chamber is open (see Figure A.1). For type II-cleaning machines, the forced ventilation system shall be interlocked with the doors at the entry and exit points, or the covers over the halogenated solvent cleaning chamber. The extract system may be switched off when the door(s) or cover(s) are closed provided that halogenated solvent emissions are prevented. NOTE Forced ventilation according to the definition (EN 12921-1:2005, 3.9) can be achieved by vacuum systems providing the function is met. 5.6.2.1.4.2 Covers, doors and enclosures A cover or door shall be fitted to all openings of the cleaning machine. The doors on type I-cleaning machines shall comply with the requirements for a sealed system. The enclosure on type II cleaning machines shall be fitted with doors at all entry and exit openings, or fitted with covers over the open area of the halogenated solvent chambers. Doors or covers can be omitted provided tha
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