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BRITISH STANDARD Medical electrical equipment Ð Capnometers for use with humans Ð Particular requirements The European Standard EN 864 : 1996 has the status of a British Standard ICS 11.040.10 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BS EN 864 : 1997 BS 5724 : Section 2.30 : 1997 BS EN 864 : 1997 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee CH/46, Lung ventilators and related equipment, upon which the following bodies were represented: Association of Anaesthetists of Great Britain and Ireland Association of British Health-care Industries Association of Paediatric Anaesthetists British Anaesthetic and Respiratory Equipment Manufacturers' Association British Paediatric Association Department of Health Electro Medical Trade Association Limited Institution of Mechanical Engineers Institution of Physics and Engineering in Medicine and Biology Intensive Care Society Safety Equipment Association This British Standard, having been prepared under the direction of the Health and Environment Sector Board, was published under the authority of the Standards Board and comes into effect on 15 May 1997 BSI 1997 Amendments issued since publication Amd No The following BSI references relate to the work on this standard: Committee reference CH/46 Draft for comment 92/57780 DC ISBN 580 27093 Date Text affected BS EN 864 : 1997 Contents Committees responsible National foreword Foreword Text of EN 864 BSI 1997 Page Inside front cover ii i BS EN 864 : 1997 National foreword This British Standard has been prepared by Technical Committee CH/46 and is the English language version of EN 864 Medical electrical equipment Ð Capnometers for use with humans Ð Particular requirements, published by the European Committee for Standardization (CEN) It supersedes BS 5724 : Section 2.30 : 1993, which is withdrawn Cross-references Publication referred to Corresponding British Standard EN 475 BS EN 475 : 1995 Medical devices Ð Electrically-generated alarm signals BS EN 1281 Anaesthetic and respiratory equipment Ð Conical connectors Part : 1996 Screw-threaded, weight-bearing connectors BS 5724 Medical electrical equipment Part : 1989 General requirements for safety BS EN 60601 Medical electrical equipment Part General requirements for safety Section 1.2 : 1993 Collateral standard Electromagnetic compatibility Requirements and tests BS EN ISO 3744 : 1995 Acoustics Ð Determination of sound power level of noise sources using sound pressure Ð Engineering method in an essentially free field over a reflecting plane BS EN 60651 : 1994 Specification for sound level meters BS EN 60801 Electromagnetic compatibility for industrial-process measurement and control equipment Part : 1993 Electrostatic discharge requirements EN 1281-2 EN 60601-1 : 1990 EN 60601-1-2 EN ISO 3744 IEC 651 IEC 801-2 Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages to 20, an inside back cover and a back cover ii BSI 1997 EN 864 EUROPEAN STANDARD NORME EUROPÊENNE EUROPẰISCHE NORM October 1996 ICS 11.040.10 Descriptors: electromedical equipment, capnometers, men, safety requirements, accident prevention, detail specifications, protection against electric shocks, protection against mechanical hazard, radiation protection, explosion proofing, fire protection, performance evaluation, tests, marking English version Medical electrical equipment Ð Capnometers for use with humans Ð Particular requirements Appareils eÂlectromeÂdicaux Ð CapnomeÁtres pour utilisation chez l'homme Ð Prescriptions particulieÁres Medizinische elektrische GeraÈte Ð Kapnometer fuÈr die Anwendung am Menschen Ð Besondere Anforderungen ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ This European Standard was approved on CEN on 1996-09-14 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 Central Secretariat 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 Central Secretariat has the same status as the official versions CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom CEN European Committee for Standardization Comite EuropeÂen de Normalisation EuropaÈisches Komitee fuÈr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1996 Copyright reserved to CEN members Ref No EN 864 : 1996 E Page EN 864 : 1996 Foreword This European Standard has been prepared by Technical Committee CEN/TC 215, Respiratory and anaesthetic equipment, the secretariat of which is held by BSI 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 April 1997, and conflicting national standards shall be withdrawn at the latest by June 1998 This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association and supports essential requirements of EU Directive(s) For relationship with EU Directives, see informative annex ZA, which is an integral part of this standard Annexes AA, BB and ZA are for information only According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom Contents Foreword Introduction Section one General Scope Normative references Terminology and definitions General requirements and general requirements for tests Classification Identification, marking and documents Power input Section two Environmental conditions Basic safety categories Removable protective means 10 Environmental conditions 11 Not used 12 Not used Section three Protection against electric shock hazards 13 General 14 Requirements related to classification 15 Limitation of voltage and/or energy Page 4 6 8 8 16 17 18 Enclosures and protective covers Separation Protective earthing, functional earthing and potential equalization 19 Continuous leakage currents and patient auxiliary currents 20 Dielectric strength Section four Protection against mechanical hazards 21 Mechanical strength 22 Moving parts 23 Surfaces, corners and edges 24 Stability in normal use 25 Expelled parts 26 Vibration and noise 27 Pneumatic and hydraulic power 28 Suspended masses Section five Protection against hazards from unwanted or excessive radiation 29 X-radiation 30 Alpha, beta, gamma, neutron radiation and other particle radiation 31 Microwave radiation 32 Light radiation (including lasers) 33 Infra-red radiation 34 Ultra-violet radiation 35 Acoustical energy (including ultrasonics) 36 Electromagnetic compatibility Section six Protection against hazards of ignition of flammable anaesthetic mixtures 37 Locations and basic requirements 38 Marking and accompanying documents 39 Common requirements for category AP and category APG equipment 40 Requirements and tests for category AP equipment, parts and components thereof 41 Requirements and tests for category APG equipment, parts and components thereof Page 8 8 8 8 8 9 ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ 9 9 9 9 10 10 10 10 10 8 BSI 1997 Page EN 864 : 1996 Page Section seven Protection against excessive temperatures, and other safety hazards 42 Excessive temperatures 43 Fire prevention 44 Overflow, spillage, leakage, humidity, ingress of liquids, cleaning, sterilization, disinfection and compatibility 45 Pressure vessels and parts subject to pressure 46 Human errors 47 Electrostatic charges 48 Biocompatibility 49 Interruption of the power supply Section eight Accuracy of operating data and protection against hazardous output 50 Accuracy of operating data 51 Protection against hazardous output Section nine Abnormal operations and fault conditions: Environmental tests 52 Abnormal operations and fault conditions 53 Environmental tests Section ten Constructional requirements 54 General 55 Enclosures and covers 56 Components and general assembly 57 Mains parts, components and layout 58 Protective earthing Ð terminals and connections 59 Construction and layout Section eleven Additional requirements specific to capnometers 101 Determination of interfering gas and vapour effects other than water vapour 102 Sustained pressure 103 Gas leakage 104 Exhaust port 105 Breathing system connections Annexes Annex AA (informative) Rationale Annex BB (informative) Bibliography Annex ZA (informative) Clauses of this European Standard addressing essential requirements or other provisions of EU Directives BSI 1997 10 10 10 10 10 10 10 10 11 13 Introduction This European Standard is one of a series based on European Standard EN 60601-1 : 1990 In EN 60601-1 this type of European Standard is referred to as a `Particular Standard' As stated in 1.3 of EN 60601-1 : 1990, the requirements of this European Standard take precedence over those of EN 60601-1 : 1990 Clauses and subclauses additional to those in EN 60601-1 : 1990 are numbered beginning `101' Additional annexes are lettered beginning `AA' Additional figures are numbered beginning `101' and additional tables are numbered beginning `101' Additional items in lettered lists are lettered beginning `aa)' The measurement of carbon dioxide in a gaseous mixture has become an increasingly common practice in many areas of clinical medicine, such as anaesthesia, respiratory therapy, paediatrics and intensive care The minimum safety requirements given in this European Standard are based on parameters that are achievable within the limits of existing technology Annex AA contains a rationale for the most important requirements It is included to provide additional insight into the reasoning that led to the requirements and recommendations that have been incorporated in this standard Clauses and subclauses marked with R after their number have corresponding rationales contained in annex AA ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ 14 14 14 14 14 14 14 14 14 14 14 14 15 15 16 17 Page EN 864 : 1996 Section one General Scope Clause of EN 60601-1 : 1990 applies except that 1.1 is replaced by the following: 1.1 This European Standard specifies requirements for the safety of capnometers as defined in 3.6 of this standard It applies to capnometers used with adults, children, and neonates It does not apply to devices intended for use as transcutaneous monitors Capnometers intended for use in laboratory research applications are outside the scope of this standard Normative references This European Standard incorporates by dated or undated reference, provisions from other publications These normative references are cited at the appropriate places in the text and the publications are listed hereafter For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision For undated references the latest edition of the publication referred to applies Appendix L of EN 60601-1 : 1990 applies with the following additions: EN 475 Medical devices Electrically-generated alarm signals prEN 737-3 Medical gas pipeline systems Ð Part 3: Pipelines for compressed medical gases and vacuum Ð Basic requirements prEN 740 : 1992 Medical electrical equipment Ð Anaesthetic workstations and their modules Ð Particular requirements prEN 1281-1 Anaesthetic and respiratory equipment Ð Conical connectors Ð Part 1: Cones and sockets EN 1281-2 Anaesthetic and respiratory equipment Ð Conical connectors Ð Part 2: Screw-threaded weight-bearing connectors (ISO 5356-2 : 1987 modified) EN 60601-1 : 1990 Medical electrical equipment Ð Part 1: General requirements for safety EN 60601-1-2 Medical electrical equipment Ð Part 1: General requirements for safety Ð Collateral standard: Electromagnetic compatibility Ð Requirements and tests EN ISO 3744 IEC 79-4 IEC 651 IEC 801-2 Acoustics Ð Determination of sound power levels of noise sources using sound pressure Ð Engineering method in an essentially freefield over a reflecting plane (ISO 3744 : 1994) Electrical apparatus for explosive gas atmospheres Ð Part 4: Method of test for ignition temperature Sound level meters Electromagnetic compatibility for industrial-process measurement and control equipment Ð Part 2: Electrostatic discharge requirements Terminology and definitions Clause of EN 60601-1 : 1990 applies with the following additions: 3.1 accuracy Quality which characterizes the ability of a device to give indications approximating to the true value of the quantity measured 3.2 alarm Signal that is activated when a monitored variable equals or crosses the alarm limit 3.3 alarm limit Reading of a monitored variable at which the alarm is first activated 3.4 alarm set point Setting of the adjustment control or display value which indicates the monitored variable's reading, at or beyond which the alarm is intended to be activated ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ NOTE Terms such as `alarm limits' or `alarm threshold' are frequently used to described the same function 3.5 alarm system Those parts of the capnometer which: a) establish the alarm limit(s); b) activate an alarm when the carbon dioxide reading is less than or equal to the low alarm set point, if provided, or is equal to or greater than the high alarm set point 3.6 capnometer Device for the measurement of carbon dioxide concentration or partial pressure in ventilatory gases NOTE The capnometer consists of all equipment including accessories, sensor and sampling tube (in the case of a diverting capnometer) specified by the manufacturer for the intended use of the capnometer 3.7 carbon dioxide level Concentration of carbon dioxide expressed in % (V/V) or the partial pressure in kPa (or mmHg) in a gaseous mixture BSI 1997 Page EN 864 : 1996 3.8 carbon dioxide reading Measured carbon dioxide level as indicated by the capnometer display 3.9 default setting; default limits Parameters first active on power up of the device 3.10 manufacturer's default setting; manufacturer's default limits Parameters first active on power up of the device as configured by the manufacturer or distributor 3.11 delay time Time from a step function change in CO2 concentration or partial pressure at the sampling site to the achievement of 10 % of final CO2 value displayed by the capnometer (time A-B in figure 101) 3.12 display Visual representation of output data 3.13 diverting capnometer; side stream capnometer Capnometer which transports a portion of the respired gases from the sampling site, through a sampling tube, to the sensor 3.14 interference with measurement accuracy Difference between the carbon dioxide reading in a corresponding mixture in which the interfering gas or vapour fraction has been replaced by nitrogen 3.15 non-diverting capnometer; non-side stream capnometer Capnometer that does not transport gas away from the sampling site 3.16 oxygen level Concentration of oxygen expressed in % (V/V) or the partial pressure in kPa (or mmHg) in a gaseous mixture 3.17 partial pressure Pressure that each gas in a gas mixture would exert if it alone occupied the volume of the mixture at the same temperature 3.18 STPD (Standard Temperature and Pressure Dry) Conditions of 273 K, ambient pressure 760 mmHg (101,3 kPa), no steam 3.19 BTPS (Body Temperature and Pressure, saturated) Conditions of 37 ÊC or 310 K, ambient pressure 750 mmHg, 100 % humidity 3.20 ATPS (Ambient Temperature and Pressure saturated) Conditions of 21 ÊC or 294 K, 750 mmHg, 100 % humidity 3.21 percent V/V carbon dioxide or other gases Level of carbon dioxide or other gas in a mixture, expressed as a percentage volume fraction 3.22 rise time Time required to achieve a rise from 10 % to 90 % of final CO2 value displayed by the capnometer when a step function change in CO2 concentration or partial pressure occurs at the sampling site (segment B-C in figure 101) ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ 100% 90% 10% A Input Time Response Figure 101 Response time (old system response) BSI 1997 B C Page EN 864 : 1996 3.23 sampling site Location at which respiratory gases are diverted for measurement to a remote sensor in a diverting capnometer or the location of the sensor area in a non-diverting capnometer 3.24 sampling tubing Conduit for transfer of ventilatory gases from the sampling site to the sensor in a diverting capnometer 3.25 sensor Part of the capnometer which is sensitive to the presence of carbon dioxide 3.26 sensor area Part of the sensor at which carbon dioxide is detected 3.27 total system response time Sum of the delay time and rise time (segment A-C in figure 101) 3.28 transcutaneous monitoring equipment Equipment and/or associated transducers for the monitoring and/or recording of partial pressures of oxygen and carbon dioxide at the skin surface 3.29 (carbon dioxide gas) transducer Device for converting the carbon dioxide partial pressure or concentration into a signal for monitoring or recording General requirements and general requirements for tests 4.1 Modifications to clause of EN 60601-1 : 1990 Clause of EN 60601-1 : 1990 applies with the following additions: 3.1 Add the following to 3.1: Packaging of equipment shall be of sufficient strength to ensure integrity of the equipment during storage and transport For sterile equipment, packaging shall ensure sterile conditions until opened, damaged or its expiration date is reached or exceeded 3.6 Add the following items: 3.6 aa) Applicable single fault conditions are: ± short and open circuits of components or wiring which can: o cause sparks to occur; or o increase the energy of sparks; or o increase temperature (see section 7); ± incorrect output resulting from software errors 3.6 bb) R An oxidant leak which is not detected by e.g an alarm or periodic inspection shall be considered a normal condition and not a single fault condition 4.2 Modification to clause of EN 60601-1 : 1990 Clause of EN 60601-1 : 1990 applies with the following addition: 4.101 Test methods other than those specified in this standard but of equal or greater accuracy may be used to verify compliance with the requirements of this standard However, in the event of a dispute, the test methods specified in this standard shall be used as reference methods Classification Clause of EN 60601-1 : 1990 applies Identification, marking and documents Clause of EN 60601-1 : 1990 applies with the following additions and modifications: In 6, replace second dash first bullet by the following: Warning statements, instructive statements or drawings, affixed in a prominent location and legible to an operator with a visual acuity of 1,0 (corrected if necessary) from a distance of 1,0 m at an illuminance level of 215 lx NOTE Operating instructions may be given on the display of the equipment In 6.1, replace item d) by the following: If the size of the capnometer does not permit the complete marking as specified throughout this clause in EN 60601-1 : 1990, at least the following shall be marked on the capnometer: ± the name of the manufacturer; ± a serial number or lot or batch identifying number; ± symbol 14 in table D.1 of EN 60601-1 : 1990 In 6.1, add the following to item f): a serial number or other lot or batch identifier In 6.1, add the following to item q): the words `not for use in breathing systems,' if applicable In 6.1, add the following additional items: aa) Capnometers not for use with inhalation anaesthetic agents shall be marked with a sentence to the effect that it is not for use with inhalation anaesthetic agents ± If moisture has an adverse effect on performance, either a statement that the operator shall see the accompanying documents for the effect of moisture on accuracy, or symbol 14 in table D.1 of EN 60601-1 : 1990 bb) Abridged operating instructions for those capnometers that are intended as free standing types of devices cc) The manufacturer shall mark the device with a warning to refer to the accompanying documents for the expected adverse effects on the performance of the capnometer when exposed to other sources of interference dd) NOTE It is recommended that illustrated service ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ information be provided to include: instructions for preventive maintenance and service calibration, and those adjustments that are necessary to maintain the capnometer in the correct operating condition, as well as a description of those adjustments and replacements that can be performed by the operator ee) All displayed measured values shall be marked in appropriate units ff) Packages shall be marked with the word `sterile' where appropriate BSI 1997 Page EN 864 : 1996 Section two Environmental conditions Basic safety categories Not used Removable protective means Not used 10 Environmental conditions Clause 10 of EN 60601-1 : 1990 applies 11 Not used 12 Not used Section three Protection against electric shock hazards 13 General Clause 13 of EN 60601-1 : 1990 applies 14 Requirements related to classification Clause 14 of EN 60601-1 : 1990 applies 15 Limitation of voltage and/or energy Clause 15 of EN 60601-1 : 1990 applies 16 Enclosures and protective covers Clause 16 of EN 60601-1 : 1990 applies 17 Separation Clause 17 of EN 60601-1 : 1990 applies 18 Protective earthing, functional earthing and potential equalization Clause 18 of EN 60601-1 : 1990 applies 19 Continuous leakage currents and patient auxiliary currents Clause 19 of EN 60601-1 : 1990 applies except for the following modification: In item 19.1e), add the following: ± For non-diverting capnometers at the sensor; ± For diverting capnometers, at the junction of the sampling tubing and the body of capnometer 20 Dielectric strength Clause 20 of EN 60601-1 : 1990 applies Section four Protection against mechanical hazards 21 Mechanical strength Clause 21 of EN 60601-1 : 1990 applies 22 Moving parts Clause 22 of EN 60601-1 : 1990 applies 23 Surfaces, corners and edges Clause 23 of EN 60601-1 : 1990 applies 24 Stability in normal use Clause 24 of EN 60601-1 : 1990 applies 25 Expelled parts Clause 25 of EN 60601-1 : 1990 applies 26 Vibration and noise Replace clause 26 of EN 60601-1 : 1990 with the following: 26.101 If a capnometer is included as a part or is integral to other equipment, the relevant standard for that equipment shall apply 26.102 If, when tested as described in 26.103, the A-weighted sound pressure level exceeds 60 dB, the circumstances under which this occurs shall be stated NOTE If an attachment intended for a particular application reduces the A-weighted sound pressure level to 60 dB(A) or below, the manufacturer should state in which part or parts of the operating range this occurs 26.103 The A-weighted sound pressure level shall be measured as follows: 26.103.1 Measuring instruments A precision sound level meter of type 1, as specified in IEC 651, shall be used Measurements shall be made with the A-weighted network in use and the `slow' meter characteristics selected A sound level meter shall have been calibrated in accordance with the manufacturer's instructions 26.103.2 Test environment Measurement shall be made in a free field over a reflecting plane such as that specified in EN ISO 3744 NOTE The necessary conditions may be achieved economically on a hard, flat surface outdoors, in a large room, or in a smaller room with sufficient sound absorptive materials on its walls and ceiling 26.103.3 Ambient conditions At the microphone positions, the A-weighted sound pressure level of the background noise shall be at least 10 dB below the sound pressure level to be measured NOTE If barometric pressure, temperature, or relative humidity deviate excessively from those of standard conditions, appropriate corrections may be required BSI 1997 Page EN 864 : 1996 26.103.4 Capnometer installation The capnometer shall be mounted as recommended in the instructions for use and in a manner typical of its intended use If it is intended to be table-mounted, the table top shall be a hard acoustically-reflecting surface unless a resilient pad is recommended in the installation instructions If it is wall-mounted, the wall shall be of a hard acoustically-reflecting material 26.103.5 Procedure Operate the capnometer over its normal working range Place the microphone at the position of maximum sound pressure level in the horizontal plane passing through the geometric centre of the capnometer and at a radius of m At each setting, if the capnometer is intended for use with a sampling tubing, make a second measurement using the recommended sampling tubing Place the sampling tubing inlet so as to lie on the specified horizontal plane, with the axis of the sampling tube vertical and 150 mm from the microphone on the axis between the capnometer and the microphone If the length of the sampling tubing does not allow this disposition, move the microphone toward the capnometer until the distance between it and the sampling tubing inlet is 150 mm If the manufacturer recommends or supplies attachments for particular diagnostic applications and states that these reduce the A-weighted sound pressure level to 60 dB or less, repeat the measurements with the attachments fitted If any such attachment incorporates a port intended for connection to an endotracheal or tracheostomy tube, connect a tube of an internal diameter equal to or greater than that of the port and at a length such that its other end will be sufficiently distant from the sound level meter not to interfere with the noise measurements 27 Pneumatic and hydraulic power Clause 27 of EN 60601-1 : 1990 applies 28 Suspended masses Clause 28 of EN 60601-1 : 1990 applies BSI 1997 Section five Protection against hazards from unwanted or excessive radiation 29 X-radiation Clause 29 of EN 60601-1 : 1990 applies 30 Alpha, beta, gamma, neutron radiation and other particle radiation Clause 30 of EN 60601-1 : 1990 applies 31 Microwave radiation Clause 31 of EN 60601-1 : 1990 applies 32 Light radiation (including lasers) Clause 32 of EN 60601-1 : 1990 applies 33 Infra-red radiation Clause 33 of EN 60601-1 : 1990 applies 34 Ultra-violet radiation Clause 34 of EN 60601-1 : 1990 applies 35 Acoustical energy (including ultrasonics) Clause 35 EN 60601-1 : 1990 applies 36 Electromagnetic compatibility Clause 36 of EN 60601-1 : 1990 applies with the following additions: 36.101 Electromagnetic compatibility The capnometer shall continue to function and meet the requirements of this European Standard or shall fail without causing a safety hazard when tested in accordance with EN 60601-1-2 If an anomaly occurs, such as display interruption, alarm activation etc it shall be possible to restore normal operation within 30 s after the electromagnetic disturbances have been applied NOTE Silencing of an activated alarm should not be considered as a failure 36.102 Electrostatic discharge Discharges shall be applied only to accessible parts and coupling planes as defined in IEC 801-2 Page 10 EN 864 : 1996 Section six Protection against hazards of ignition of flammable anaesthetic mixtures 37 Locations and basic requirements Clause 37 of EN 60601-1 : 1990 applies with the following addition: 37.101 Anaesthetic agents which are not ignited by the test in Annex M of prEN 740 : 1992 shall be regarded as non-flammable anaesthetic agents 38 Marking and accompanying documents Clause 38 of EN 60601-1 : 1990 applies 39 Common requirements for category AP and category APG equipment Clause 39 of EN 60601-1 : 1990 applies 40 Requirements and tests for category AP equipment, parts and components thereof Clause 40 of EN 60601-1 : 1990 applies 41 Requirements and tests for category APG equipment, parts and components thereof Clause 41 of EN EN 60601-1 : 1990 applies Section seven Protection against excessive temperatures, and other safety hazards 42 Excessive temperatures Clause 42 of EN 60601-1 : 1990 applies 43 R Fire prevention Clause 43 of EN 60601-1 : 1990 applies with the following addition: In order to reduce the risk to patients, other persons or the surroundings due to fire, ignitable material, under normal and single fault conditions, shall not, at the same time, be subjected to conditions in which: ± the temperature of the material is raised to its minimum ignition temperature; and ± an oxidant is present The minimum ignition temperature is determined in accordance with IEC 79-4 using the oxidizing conditions present under the normal and single fault condition Compliance is checked by determining the temperature the material is raised to under the normal and single fault condition If sparking can occur under a normal or a single fault condition, the materials subjected to the energy dissipation of the spark shall not ignite under the oxidizing conditions present Compliance is checked by observing if ignition occurs under the most unfavourable combination of normal conditions with a single fault 44 Overflow, spillage, leakage, humidity, ingress of liquids, cleaning, sterilization, disinfection and compatibility Clause 44 of EN 60601-1 : 1990 applies with the following modifications: Replace the first paragraph of 44.3 by the following: During and after the test as described in subclause 44.3 of EN 60601-1 : 1990: ± the capnometer shall be so constructed that the spillage does not wet parts which can cause a safety hazard; ± the capnometer shall continue to function within the tolerances specified by the manufacturer for normal use Add the following: 44.101 Condensation effects The manufacturer shall disclose in the accompanying documents the effects on the performance of the capnometer (other than accuracy) of the test listed in 50.102.4 44.102 Obstruction of the sensing area of sampling tubing The capnometer, if a diverting type, shall have a means of indicating obstruction of the sensing area or sampling tubing Compliance shall be checked by totally obstructing the sensing area or sampling tubing at the sampling site 44.103 Contamination of breathing systems It shall not be possible to reverse the direction of flow through the sampling tube in order to purge the capnometer Compliance shall be checked by inspection 45 Pressure vessels and parts subject to pressure Clause 45 of EN 60601-1 : 1990 applies 46 Human errors Replace clause 46 of EN 60601-1 : 1990 with the following: 46.101 Gas connections for calibration gases mixtures other than those specified in prEN 737-3, shall not be interchangeable with NIST (non-interchangeable screw-threaded) and pin index systems, and if colour coded shall be colour-coded differently from those colours used for medical gases 47 Electrostatic charges Not used 48 Biocompatibility Clause 48 of EN 60601-1 : 1990 applies 49 Interruption of the power supply Clause 49 of EN 60601-1 : 1990 applies BSI 1997 Page 11 EN 864 : 1996 Section eight Accuracy of operating data and protection against hazardous output 50 Accuracy of operating data Clause 50 EN 60601-1 : 1990 applies with the following additions: 50.101 R Measurement accuracy Carbon dioxide reading shall be ± 12 % of the actual test gas value or ± 0,53 kPa (4 mmHg), whichever is greater, over the full range of capnometer readings corrected to 101,3 kPa (760 mmHg) Compliance shall be checked by the test given in 50.102 50.102 Test method 50.102.1 Principle Carbon dioxide readings are determined at a number of carbon dioxide levels spanning the capnometer measurement range 50.102.2 Procedure The capnometer shall be set up in accordance with the accompanying documents and tested using the test gas mixtures as described in 50.102.3 and 50.102.4 50.102.3 Dry gas testing Carry out the tests using the mixtures and conditions given in table 101 Table 101 Dry gas testing % V/V Carbon dioxide1) Balance2) 0; 2,5; 5,0; 10,0 0; 2,5; 5,0; 10,0 Nitrogen Air 1) 2) CO2 content, % (V/V) at ambient pressure, 23 ÊC, dry gas Mixtures used at (23 ± 2) ÊC, % relative humidity 50.102.4 Saturated gas testing After 24 h of continuous operation with the capnometer connected to a simulated breathing system containing air fully saturated with water at 37 ÊC, and cycling at a frequency of 10 breaths per minute between a pressure of ambient and 3,5 kPa (35 cmH2O) above ambient, perform an accuracy test using the mixtures and conditions given in table 102 Table 102 Saturated gas testing following use in a simulated breathing system % V/V Carbon dioxide1) Balance2) 0; 2,5; 5,0; 10,0 Nitrogen 0; 2,5; 5,0; 10,0 Air 1) CO2 content, % (V/V) at ambient pressure, 37 ÊC, 100 % saturated with water vapour 2) Mixtures used at (37 ± 2) ÊC, 100 % r.h BSI 1997 50.103 Stability of measurement accuracy The capnometer shall meet the requirements specified in 50.101 for no less than 24 h when used in accordance with the accompanying documents Compliance shall be checked by the test given in 50.104 50.104 Test method Repeat the tests given in 50.102.3 after 24 h operation as described in 50.102.4 50.105 Rise time The manufacturer shall disclose in the accompanying documents the rise time for a 10 % to 90 % step change in concentration when tested as described in 50.106 (both increase and decrease in concentration), and shall also disclose the flow required to meet the disclosed rise time 50.106 Test method The capnometer shall be set up in accordance with the accompanying documents and arranged as in figure 102 Connect the carbon dioxide signal output of the capnometer to a suitable recording device Pass dry air at ambient temperature and at a flow of 10 l/min through the test apparatus and the capnometer switched to normal function By means of the three-way tap, a dry calibrated gas at ambient temperature containing approximately % (V/V) of carbon dioxide is passed through the apparatus and the rise time calculated Repeat the above procedure, switching from % (V/V) carbon dioxide to air 50.107 Displays Carbon dioxide level displays shall be marked with kPa, % (V/V ) CO2 or mmHg NOTE The displays should not be obscured by the hand normally adjusting the control(s) associated with the display Page 12 EN 864 : 1996 Recorder or oscilloscope CO2 reading Capnometer Sample tube or sensor connection Connection volume ≤ ml Sensor or adaptor for sample tube (10 +- 0,5) l/min air (10 +- 0,5) l/min mixture with 5% (V/V) CO2 (calibrated) with balance air Three-way tap Figure 102 Test apparatus to determine response time BSI 1997 Page 13 EN 864 : 1996 51 Protection against hazardous output Clause 51 of EN 60601-1 : 1990 is replaced by the following: 51.1 Control function and position Positions of controls shall be clearly distinguishable Calibration controls shall be protected against inadvertent adjustment Operator-operable function checks other than `power on' for tests controls such as battery condition or signal operation should automatically return from the check, test, or override position All other controls should also include means to prevent inadvertent changes from the intended position and should have clearly distinguishable positions 51.2 Movement of controls Controls and their associated markings shall be visible and/or legible to an operator having a visual acuity (corrected if necessary) of at least 1,0 when the operator is located m in front of the capnometer at an illuminance of 215 lx Markings shall be clearly identified with their associated controls NOTE Attention is drawn to the fact that the ISO convention for adjustment of rotary controls in pneumatic and fluidic systems is contrary to the IEC convention for electronic controls Manufacturers should ensure consistency and clarity of rotary controls on a modular basis 51.3 Alarms 51.3.1 Alarm prioritization The alarms of the capnometer are grouped in three categories: high priority, medium priority, low priority and the corresponding signal shall have the characteristics specified in EN 475 51.3.1.1 The auditory components of these alarms should allow silencing by the operator until the capnometer is placed in use (i.e connected to the patient) in order to reduce nuisance alarms 51.3.1.2 The set points of adjustable alarms shall be indicated continuously or on operator demand 51.3.2 High priority signal When a high priority signal is activated and when the condition causing the alarm has cleared, the auditory component shall reset automatically The duration of the auditory signal shall not be less than one complete burst 51.3.3 Medium priority signal When a medium priority signal is activated and when the condition causing the alarm has been cleared, the auditory component shall reset automatically The duration of the auditory signal shall not be less than one complete burst BSI 1997 51.4 Alarm characteristics (See also subclause 51.3.1.) 51.4.1 When the capnometer is not only to test the respiratory functions, it shall have a high carbon dioxide reading alarm for both inspired and exhaled carbon dioxide and a low carbon dioxide reading alarm for exhaled carbon dioxide 51.4.2 Alarm set points for both high and low carbon dioxide reading alarms shall be operator-adjustable 51.4.3 When the capnometer is switched on, the carbon dioxide reading alarms for carbon dioxide shall be of medium priority 51.4.4 If the capnometer has an operator-adjustable high carbon dioxide reading alarm priority control it shall allow the operator to change the alarm priority between the medium and high priority only after the capnometer is switched on 51.4.5 If the capnometer has an automatic change in alarm priority setting, it shall change only to a higher alarm priority Compliance shall be checked by inspection 51.4.6 The difference between the alarm set point and the carbon dioxide reading when the alarm is activated shall not exceed 0,2 volumes percent (0,187 kPa or 1,4 mmHg at 101,3 kPa or 760 mmHg barometric pressure under conditions specified by the manufacturer) carbon dioxide Compliance shall be checked by the following: Generate at least four stable carbon dioxide readings that span the range of the alarm system in approximately equal steps by varying the carbon dioxide level delivered to the sensor, or by electrical simulation, or by adjusting the calibration control (if provided) For each carbon dioxide reading, adjust the alarm set point so that the alarm is deactivated Incrementally adjust the alarm set point until the alarm is activated and record the carbon dioxide reading at which the alarm is activated The difference between the alarm set point and the corresponding carbon dioxide reading shall not exceed 0,2 volumes percent 51.5 Announcement of alarm condition 51.5.1 Operator-adjustable default parameters shall require a deliberate sequence of actions Temporary silencing of auditory alarms, if provided, shall not exceed The visual signals shall remain until the alarming condition no longer exists If permanent disabling of the auditory signal is provided, it shall require deliberate action on the part of the operator The visual indication shall remain until the alarming condition no longer exists 51.5.2 All alarms shall be provided with a default setting Page 14 EN 864 : 1996 Section nine Abnormal operations and fault conditions: Environmental tests Table 103 Inhalation anaesthetics and other interfering gases and vapours 52 Abnormal operations and fault conditions Clause 52 of EN 60601-1 : 1990 applies 53 Environmental tests Clause 53 of EN 60601-1 : 1990 applies Gas or vapour Level % (V/V) (Balance dry nitrogen) Oxygen 95 % Nitrous oxide1) 80 % Halothane1) 3% Section ten Constructional requirements Enflurane1) 5% Isoflurane1) 5% 54 General Clause 54 of EN 60601-1 : 1990 applies 55 Enclosures and covers Clause 55 of EN 60601-1 : 1990 applies 56 Components and general assembly Clause 56 of EN 60601-1 : 1990 applies with the following addition: 56.101 Sevoflurane1) 5% Desflurane1) 15 % NOTE Components of the capnometer should be made of materials that are compatible with the gases and agents with which those components are designed to come into contact 57 Mains parts, components and layout Clause 57 of EN 60601-1 : 1990 applies 58 Protective earthing-terminals and connections Clause 58 of EN 60601-1 : 1990 applies 59 Construction and layout Clause 59 of EN 60601-1 : 1990 applies Section eleven Additional requirements specific to capnometers 101 Determination of interfering gas and vapour effects other than water vapour Determine the accuracy of carbon dioxide reading in the presence of interfering gases and vapours at the levels given in table 103 All gases used for this test shall be dry and premixed with a CO2 volume content of % and with an interfering gas or vapour content as specified in table 103, in a balance of nitrogen Determine the carbon dioxide reading while the sensor is exposed to test gas mixtures for a continuous period of h each 1) Inhalation anaesthetic agent 102 Sustained pressure 102.1 Capnometers shall meet the requirements given in 50.101 and 50.105 following exposure to a sustained positive pressure of 10 kPa (100 cmH2O) and negative pressure of 1,5 kPa (15 cmH2O), each for 30 s, or shall be marked accordingly (see 6.1) Compliance shall be checked by following the test given in 102.2 102.2 Compliance shall be tested as follows: 102.2.1 Principle The accuracy of the carbon dioxide reading and the rise time are determined after exposure of the sampling site to sustained pressure 102.2.2 Procedure Expose the sampling site to a sustained positive pressure with respect to ambient of (10 ± 1) kPa ((100 ± 10) cmH2O) and a sustained negative pressure with respect to ambient of (1,5 ± 0,2) kPa ((15 ± 2) cmH2O), in turn, for not less than 30 s each Repeat this procedure four times, then carry out the test for measurement accuracy as described in 50.102 and the test for rise time as described in 50.106 103 Gas leakage The gas leakage of the capnometer shall not exceed 20 ml/min at a pressure of kPa (30 cmH2O) Compliance shall be checked by determining the leakage 104 Exhaust port An exhaust port shall be provided to collect or route the diverted gas from the capnometer, and this exhaust port shall be incompatible with the inlet port of the capnometer Compliance shall be checked by inspection BSI 1997 Page 15 EN 864 : 1996 105 Breathing system connections If the capnometer is intended to be connected to a breathing system, the breathing system connection ports shall be a 15 mm and/or 22 mm conical connector in compliance with prEN 1281-1 or EN 1281-2 Diverting capnometers shall be provided with a means to return or route diverted gases to an appropriate place of discharge If an exhaust port is provided it shall be non-interchangeable with the inlet port and shall not accept a 15 mm and/or 22 mm conical connector as specified in prEN 1281-1 or EN 1281-2 Compliance is checked by inspection Annexes Appendices A to K of EN 60601-1 : 1990 apply Annex AA (informative) Rationale AA.4.1(3.6bb)) A fault which is not detected can exist for a long time Under those circumstances it is not acceptable to regard a further fault as a second fault which can be disregarded Such a first fault is regarded as a normal condition AA.6.8.2.aa), first dash The intended use should be emphasized especially if it is for testing the respiratory functions AA.6.8.2.aa), third dash If the suctioned gases are disposed of into the anaesthetic gas scavenging system, it should be stated whether or not there is an effect on the capnometer by low pressure within the anaesthetic gas scavenging system AA.43 Reports of fire caused by medical devices are unusual However, when such fires occur in the hospital environment they can have tragic consequences The risk of a fire is fundamentally determined by the three elements which are necessary in order to start a fire: ± ignitable material (fuel); ± a temperature equal to or above the minimum ignition temperature of the material or sparks with energy dissipation equal to or above the minimum ignition energy of the materials; ± an oxidant Therefore, following the basic safety concepts of EN 60601-1 : 1990, the objective in the design of the equipment is to ensure that under both normal and single fault conditions and under the oxidizing conditions to which the material may be exposed, the temperature of any material is not raised to its minimum ignition temperature or the spark energy does not exceed the material ignition energy level Alternatively, contained ignition may occur provided it is self-limiting so that no hazard is created, e.g a fuse or resistor within a sealed compartment BSI 1997 Minimum ignition temperatures for a large number of specific materials are well established in published literature, although usually only for ambient air and pure oxygen environments The minimum ignition temperature may be critically dependent upon the concentration of oxidant present If ignition temperatures for other materials or different oxygen concentrations are required these can be determined using the methods and apparatus described in IEC 79-4 In considering the ignitable materials particular attention should be paid to materials which may accumulate during prolonged use, e.g., airborne particles of paper or cotton The risk of fire directly caused by sparking of electrical circuits is generally considered insignificant in medical equipment as temperature rise resulting from the power dissipation caused by a spark will not normally reach the ignition temperature of the solid materials generally used when following good design practice However, if materials with a low ignition temperature and a very low thermal capacity, e.g., cotton wool, paper or organic fibre accumulations, are present then it may not be possible to determine the surface temperatures attained during exposure to spark energy and specific tests, e.g., ignition tests, may be necessary to assume safety under these conditions In certain standards currently in use the requirements to minimize fire risk are based on limitation of temperature, electrical energy and oxidant concentration to absolute values The temperature value is based on the minimum hotplate ignition temperature for fire retardant cotton in 100 % oxygen which is given in the American NFPA publication 53 M as 310 ÊC The assumption was therefore made that 300 ÊC was an acceptable temperature limit in medical equipment with oxygen enriched atmospheres The origin of the electrical energy values which have been used is less clear and it would seem that, in the absence of specific controlled tests, figures have been adopted from accepted working practices or from tests performed in other environments However, simple tests and detailed analysis of the known factors involved in causing an oxygen fire show that these figures can be either over-restrictive or potentially hazardous depending, in particular, on the manner in which the power may be dissipated and the proximity and type of any `fuel' present It is now generally accepted that there are no single or universally applicable ranges of temperature, energy and concentration of oxidant which can ensure safety under all circumstances Ultimately, electrical energy is only significant in respect of its ability to raise the temperature of ignitable materials and this in turn depends upon the particular configuration and the proximity of any ignitable materials Page 16 EN 864 : 1996 Under single fault conditions in a typical electrical circuit the possible number of failure modes is very high In this case full assurance of safety may only be possible by the use of appropriate hazard and safety analysis procedures, taking into consideration the three basic elements, i.e., material, temperature and oxidant An appropriate design might limit the electrical energy in the circuit to ensure that temperatures remain below the minimum air ignition temperature under normal conditions and seal compartments or add forced ventilation to ensure that the oxygen content does not exceed that of ambient air under a single fault condition Alternatively, it may be appropriate to limit the electrical energy to ensure temperatures below the minimum ignition temperature for a pure oxygen environment, even under single fault condition The particular combination of material, oxidant and temperature determines whether a fire will occur, not a single value of any one of these variables AA.50.101 Accurate knowledge of inspired and exhaled carbon dioxide concentration provides the clinician with vital patient ventilatory information regarding the patient's status, the function of the airway, and the integrity of the breathing circuit Adjustments to pulmonary ventilation are often based on values of exhaled carbon dioxide Recognition of unintended oesophageal intubation, disconnection of the patient from the ventilator, partial and complete airway obstruction, and rebreathing of exhaled carbon dioxide from the breathing system are often first recognized by changes in the respired carbon dioxide concentrations 1) Annex BB (informative) Bibliography NFPA Publication 53 M Fire hazards in oxygen-enriched atmospheres1) Available from the National Fire Protection Association, Batterymarch Park, PO Box 9101, Quincy MA 02269-9101, USA BSI 1997