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Tiêu đề Medical Electrical Equipment — Particular Requirements For The Basic Safety And Essential Performance Of Respiratory Gas Monitors
Trường học International Organization for Standardization
Chuyên ngành Medical Electrical Equipment
Thể loại tiêu chuẩn
Năm xuất bản 2004
Thành phố Geneva
Định dạng
Số trang 50
Dung lượng 342,03 KB

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Cấu trúc

  • 6.1 Marking on the outside of equipment or equipment parts (13)
  • 6.3 Markings of controls and instruments (13)
  • 10.1 Transport and storage (16)
    • 10.2.2 Power supply (16)
  • 44.3 Spillage (22)
  • 44.7 Cleaning, sterilization and disinfection (22)
  • 44.8 Compatibility with substances used with the equipment (22)
  • 56.7 Batteries (28)
  • 57.3 Power supply cords (29)

Nội dung

Microsoft Word C034637e doc Reference number ISO 21647 2004(E) © ISO 2004 INTERNATIONAL STANDARD ISO 21647 First edition 2004 11 15 Medical electrical equipment — Particular requirements for the basic[.]

Marking on the outside of equipment or equipment parts

Replacement: d) If the size of the RGM does not permit the complete marking as specified throughout this clause, at least the following shall be marked on the RGM:

 the name and address of the manufacturer or authorized representative, if applicable;

 a serial (or Symbol 3.16 from ISO 15223:2000) or lot or batch (or Symbol 3.14 from ISO 15223:2000) identifying number; and

All operator-interchangeable components of a respiratory gas monitor (RGM) that are sensitive to flow direction must be clearly marked with an arrow indicating the gas flow direction The gas sampling inlet should be labeled with the text “Gas sample” or the ISO 7000-0794 symbol, while the gas sampling outlet must display “Gas exhaust” or the ISO 7000-0795 symbol Packages for single-use components need to be marked with “Single use,” “Single patient use,” or the ISO 7000-1051 symbol If the RGM includes latex components, it must be labeled with the word “Latex.” Additionally, if applicable, the use-by date or the ISO 15223:2000 Symbol 3.12 should be included All sampling tubes should also be marked with “Gas sample” or the corresponding symbol.

The gas exhaust tube for a diverting respiratory gas monitor must be clearly labeled with the text "Gas exhaust" or the Symbol ISO 7000-0795 Additionally, the respiratory gas monitor (RGM) and its components should include proper disposal markings as necessary.

Markings of controls and instruments

Amendment Add at the beginning:

Gas reading should be marked in kilopascals (kPa)

Amendment Add after last dash:

Units outside the International System, which alternatively may be used on an RGM:

 gas reading of anaesthetic agents

 MAC (minimum alveolar concentration) can be displayed additionally (see Table 107)

Addition: aa) Description of the intended use of the RGM; bb) A description of the principles of operation of the RGM;

It is essential to provide illustrated service information that outlines preventive maintenance instructions, service calibration, and necessary adjustments to keep the RGM operating correctly Additionally, the information should describe user-performable adjustments and replacements Instructions for use must include relevant details as applicable.

The performance specifications for a diverting respiratory gas monitor (RGM) include critical parameters such as the sampled gas flow rates and their tolerances, the alarm limit range for gas readings, and the detection thresholds for both single and multiple halogenated anesthetic gases in a gas mixture Additionally, the specifications outline the operational and storage ranges for temperature, atmospheric pressure, and humidity, as well as the time required to achieve specified operating performance after activation It is essential to note the maximum interval, in hours, between necessary operator interventions for the water-handling system, based on specific temperature and humidity conditions, for both minimum and maximum sample flow rates The RGM's capabilities regarding automatic barometric pressure compensation, the MAC values or algorithms used for gas readings, total system response time, and measurement accuracy drift are also crucial components of the performance specifications.

The performance of the system can be adversely affected by several factors, including the quantitative impacts of humidity and condensate, leaks or internal venting of the sampled gas, and cyclical pressure variations of up to 10 kPa (100 cmH₂O) Additionally, fluctuations in barometric pressure, the return of sampled gas to the breathing system, variations in supply mains or battery voltage, as well as the presence of interfering gases and vapors, contribute to potential performance issues Other sources of interference may also play a role in affecting the overall functionality.

The operation and maintenance of the RGM involve several critical procedures, including calibration guidelines and proper disposal of calibration gases Essential functional checks must be performed before or during use, alongside routine inspections and testing at specified frequencies Cleaning, disinfecting, or sterilizing methods should be outlined, including limitations on the number of cycles Proper connection of the RGM's exhaust port to an anaesthetic gas scavenging system is necessary, with advice on the disposal of sampled gases Verification of all operator-adjustable alarm system functions is crucial, as is understanding the rated voltage range for external power sources and the minimum value for internal power sources during normal operation The RGM's functionality after a power interruption exceeding 30 seconds must be addressed, along with guidelines for disposing of accumulated fluids A diagram illustrating the RGM's features, including the location and function of all controls and components, is essential for correct operation Additionally, the article should cover the correct installation of the RGM, sampling arrangements, and any necessary connecting tubing Information regarding the disposal of the RGM and its components, the location of latex-based components, and suitability for use in MRI environments, including the maximum magnetic field, should also be included.

Position the RGM or its components to align with the operator's intended viewpoint, which should be located at any point within a cone defined by a 30° angle to the axis perpendicular to the center of the marking plane, at a distance of 1 m ± 0.025 m Ensure that the ambient illuminance is maintained between 100 lx and 1,500 lx.

The observer must possess a visual acuity of 0 on the log Mean Angle Resolvable (log MAR) scale, equivalent to 6/6 (20/20), with corrections applied if needed Additionally, the observer is required to accurately identify the marking from their viewpoint.

IEC 60601-1:1988, Clause 10, applies, except as follows.

Transport and storage

Power supply

Addition: aa) When the RGM is intended for use during patient transport outside a healthcare facility, it shall be suitable for a power supply having

 DC voltage: −15 % to +25 % of nominal value, or

 AC voltage: −25 % to +15 % of nominal value, and

 AC frequency: −5 % to +5 % of nominal value, and

 AC waveform: sine, square and others specified by the manufacturer in the accompanying documents

15 Limitation of voltage and/or energy

18 Protective earthing, functional earthing and potential equalization

19 Continuous leakage currents and patient auxiliary currents

IEC 60601-1:1988, Clause 21, applies, except as follows

An RGM and its components not designed for patient transport outside a healthcare facility must possess sufficient mechanical strength to withstand normal use, including pushing, impact, dropping, and rough handling Stationary equipment is not subject to these requirements Following the specified tests, including shock testing per IEC 60068-2-27, the RGM should not present any safety hazards and must operate normally.

 number of shocks: 3 shocks per direction per axis (18 total)

NOTE A hand-held RGM tested and complying with the requirements in 21.5 of IEC 60601-1:1988 is considered to comply with this requirement b) Broad-band random vibration, in accordance with IEC 60068-2-64

 frequency range: 10 Hz to 2 000 Hz;

 100 Hz to 200 Hz: −3 db/octave,

 duration: 10 min per each perpendicular axis (3 total)

21.102 Shock and vibration for transport

An RGM and its components must possess sufficient mechanical strength to withstand the mechanical stresses encountered during patient transport outside healthcare facilities, including normal use, pushing, impacts, drops, and rough handling.

After the following tests, the RGM shall not cause a safety hazard and shall function normally

NOTE Equipment tested and complying with the requirements in 21.102 in total or part, is considered to comply with the corresponding requirements of 21.101 a) Shock, in accordance with IEC 60068-2-27:1987

 number of shocks: 3 shocks per direction per axis (18 total)

11 b) Broad-band random vibration, in accordance with IEC 60068-2-64

 frequency range: 10 Hz to 2 000 Hz;

 100 Hz to 200 Hz: −7 db/octave,

 duration: 30 min per each perpendicular axis (3 total) c) For mobile equipment, free fall, in accordance with IEC 60068-2-32:1975, using Procedure 1:

 direction: vertical, (normal operating position) d) For portable equipment, free fall, in accordance with IEC 60068-2-32:1975, using Procedure 2:

 direction: on each of the six surfaces

NOTE For portable equipment, which is intended to be used with a carrying case, that case may be applied to the equipment during this test

30 Alpha, beta, gamma, neutron radiation and other particle radiation

IEC 60601-1:1988, Clause 36, applies, except as follows

Respiratory gas monitors shall not be considered life-supporting equipment or systems as defined in

IEC 60601-1-2:2001 An RGM shall meet the appropriate requirements of IEC 60601-1-2:2001

An RGM designed for patient transport outside a healthcare facility must adhere to IEC 60601-1-2:2001 standards, specifically section 36.202.3 a) 1) It should meet the immunity test level of 20 V/m, with 80% amplitude modulation at 1,000 Hz, across the frequency range of 80 MHz to 2,500 MHz, as detailed in Table 209 of the IEC 60601-1-2:2001 standard.

39 Common requirements for category AP and category APG equipment

IEC 60601-1:1988, Clause 39, does not apply

40 Requirements and tests for category AP equipment, parts and components thereof

IEC 60601-1:1988, Clause 40, does not apply

41 Requirements and tests for category APG equipment, parts and components thereof

IEC 60601-1:1988, Clause 41, does not apply

IEC 60601-1:1988, Clause 43, applies, except as follows

To minimize risks to patients, individuals, and the environment from fire hazards, it is essential that ignitable materials are not exposed to conditions that could lead to ignition under both normal and single fault scenarios when using 43.101 RGM in conjunction with oxidants.

 the temperature of the material is raised to its minimum ignition temperature; and

NOTE For partial pressures of oxygen up to 27,5 kPa, when no other oxidants are present, the requirements in IEC 60601-1:1988 are considered to be sufficient

The minimum ignition temperature is determined in accordance with IEC 60079-4 using the oxidizing conditions present under normal and single fault condition

Compliance is assessed by measuring the temperature to which the material is heated under both normal and single fault conditions Additionally, if sparking is possible in these conditions, the material must not ignite when exposed to the energy released by the spark in the existing oxidizing environment.

Compliance shall be checked by observing if ignition occurs under the most unfavorable combination of normal conditions with a single fault

44 Overflow, spillage, leakage, humidity, ingress of liquids, cleaning, sterilization, disinfection and compatibility

IEC 60601-1:1988, Clause 44, applies, except as follows.

Spillage

Amendment (replace the first sentence with the following):

An RGM and its components shall be so constructed that spillage does not wet component parts which when wetted can cause a safety hazard.

Cleaning, sterilization and disinfection

All components that are not designated by the manufacturer for single patient use and that come into contact with exhaled patient gas, which may be rebreathed, must either be capable of being sterilized or disinfected, or must include a breathing system filter that complies with ISO 23328 standards.

Compliance shall be checked by a review of the accompanying documents for methods of sterilization and disinfection [see 6.8.2 cc) 3) iv)], and by inspection of the relevant validation reports.

Compatibility with substances used with the equipment

The RGM and parts thereof shall be designed and manufactured to minimize health risks due to substances leached from the RGM or its components during normal use

Particular attention should be paid to the toxicity of materials and their compatibility with substances and gases with which they enter into contact during normal use or routine procedures

Compliance shall be checked by inspection of the relevant validation reports

45 Pressure vessels and parts subject to pressure

IEC 60601-1:1988, Clause 46, applies, except as follows

49 Interruption of the power supply

IEC 60601-1:1988, Clause 49, applies, except as follows

The RGM shall provide at least a medium priority alarm signal when the power falls below the minimum value for normal operation

NOTE After the loss of power, the alarm system is not expected to repeat alarm signals indefinitely

An internal electrical power source for the RGM must trigger a low priority alarm signal before the power level drops below the minimum required for normal operation This alarm should include an auditory component and repeat, ensuring that there is adequate time to replace the internal power source.

The RGM shall not display the respiratory gas reading when the external electrical power source falls below the minimum value for normal operation

Compliance shall be checked by functional testing

49.102 Settings and data storage following short interruptions or automatic switchover

In the event of a supply interruption to the RGM lasting less than 30 seconds, or during an automatic transition to an internal power source, all settings and stored patient data will remain unchanged.

NOTE 1 The RGM does not have to be operating during the interruption of the supply mains

NOTE 2 Settings includes operator settings, user settings, and the mode of operation

Compliance shall be checked by functional testing

There shall be a continual visual indication when the RGM is operating from the reserve electrical power source

The RGM must include a backup electrical power source that ensures a minimum of 30 minutes of normal operation, adhering to the conditions outlined in the user instructions.

Compliance shall be checked by functional testing

49.104 Reserve electrical power source for use outside the healthcare facility

An RGM designed for patient transport outside healthcare facilities must include either an internal electrical power supply or a backup power source, ensuring at least one hour of normal operation.

Compliance is verified by ensuring that normal operations can continue for at least one hour after the primary power source is disconnected, utilizing either the reserve electrical power source or the internal electrical power supply.

IEC 60601-1:1988, Clause 51, applies, except as follows

For each respiratory gas that an RGM is intended to monitor, the measurement accuracy levels given in

Table 101 must be met, detailing the gas reading range, measurement accuracy, and the minimum sample flow rate required for the RGM to achieve specified measurement accuracy, all of which will be provided in the instructions for use.

Gas levels in % volume fraction

Halogenated agent ± (volume fraction of 0,2 % + 15 % of gas level)

CO 2 ± (volume fraction of 0,43 % + 8 % of gas level) Nitrous oxide ± (volume fraction of 2,0 % + 8 % of gas level)

O 2 ± (volume fraction of 2,5 % + 2,5 % gas level)

Compliance shall be checked by inspection of the instructions for use and with the following test:

After exposing the sampling site 10 times to a cyclical pressure in accordance with Figure 101, gas readings

Figure 101 — Cyclical ambient pressure waveform

Use test gas with a gas level as indicated in Table 102 and a tolerance of less than 0,2 times the error tolerance given in Table 101

Table 102 — Mixtures for measurement accuracy, drift, and total system response time measurement

Gas levels in % volume fraction

Halothane a Enflurane a Isoflurane a Sevoflurane a Desflurane a Oxygen Carbon dioxide

Ensure a balance of 100.0 when the RGM is intended for use with this gas If the specified value is lower, use the full-scale reading This mixture is essential for conducting drift measurement accuracy tests and for evaluating the total system response time, if applicable.

Test gases with the specified accuracy can be sourced from manufacturers or produced in-house, ensuring the required gas mixtures are verified through alternative methods such as mass spectrometry or refractometry.

The proper disposal of test gas mixtures should be considered

To ensure accurate measurements, set up and calibrate the RGM following the provided instructions, and conduct tests with the specified test gas mixtures from Table 102 Confirm that the respiratory gas levels displayed numerically meet the measurement accuracy standards outlined in Table 101.

Each respiratory gas monitored by an RGM must maintain measurement accuracy drift that complies with the requirements outlined in Table 101 for a minimum of 6 hours, provided it is used according to the instructions for gas mixtures specified in Table 102 Additionally, the drift of measurement accuracy must be clearly stated in the instructions for use.

Compliance shall be checked by inspection of the instructions for use and with the following test:

To ensure accurate measurement with the RGM, it is essential to set it up, calibrate, and operate it according to the provided instructions Conduct tests as specified in 51.101.1 using the designated test gases for drift measurement accuracy, as outlined in Table 102 Sample each identified test gas mixture at least three times over a six-hour period, with sampling occurring every three hours Between sampling intervals, allow the RGM to sample ambient air, and ensure proper disposal of the test gas mixtures.

Verify that the measurement accuracy requirements of Table 101 are met at each sample point at each test gas level

51.101.3 Measurement accuracy of gas readings for gas mixtures

To ensure accurate monitoring of respiratory gases by an RGM, the measurement accuracy of gas readings in mixtures must align with the specifications outlined in Table 101, utilizing the gas mixtures listed in Table 103.

Compliance shall be checked by inspection of the instructions for use and with the following test:

To ensure accurate measurements, set up and calibrate the RGM according to the provided instructions, testing it with the gases listed in Table 103 at an ambient temperature of 23 °C ± 2 °C Confirm that the displayed respiratory gas levels meet the accuracy standards outlined in Table 101 Additionally, consider the proper disposal methods for test gas mixtures.

Use test gas mixtures with gas levels as indicated in Table 103 and a tolerance of less than 0,2 times the error tolerance given in Table 101

Table 103 — Mixtures for combined gas measurement accuracy testing

Gas levels in % volume fraction

Oxygen Nitrogen b Halothane a Enflurane a Isoflurane a Sevoflurane a Desflurane a

5 Balance c 60 a Included if the RGM is intended for use with these gas mixtures b For test gases prepared in-house, nitrous oxide can be increased to “balance” and nitrogen eliminated

Total system response time shall be disclosed in the instructions for use

For a diverting respiratory gas monitor, the manufacturer shall disclose total system response time at each of its specified gas diversion flowrates See also 6.8.2 cc) 1) ix)

Compliance shall be checked by inspection of the instructions for use and with the following test:

To ensure accurate testing, set up the RGM according to the provided instructions and connect it to the test apparatus as illustrated in Figure 102 Additionally, it is important to consider the proper disposal of test gas mixtures.

Connect the RGM to a suitable recording device

To evaluate the total system response time, use the gas mixture specified in Table 102 at a flow rate of 60 l/min for a 20 mm bore size Cycle the valve(s) and document the response time, repeating this process 20 times to calculate the average total system response time.

3 two 3-way valves (non-mixing), power supply controlled

6 compressed air or calibrated test gas

Figure 102 — Respiratory gas monitor — Test apparatus for total system response time

51.103 Indication of gas readings units of measure

Batteries

57 Mains parts, components and layout

IEC 60601-1:1988, Clause 57, applies, except as follows

Power supply cords

Addition: aa) Any detachable power supply cord of an RGM shall be protected against accidental disconnection at the appliance inlet

Compliance shall be checked by the following test:

Subject the detachable power supply cord for 1 min to an axial pull force as given in Table 104

During the test, a failure occurs if the mains connector becomes disconnected from the appliance inlet

Table 104 — Pull force as a function of RGM mass

Up to and including 1 30 Over 1 up to and including 4 60

58 Protective earthing — terminals and connections

101 Additional requirements specifically related to respiratory gas monitors

101.1 Interfering gas and vapour effects

The instructions for use must disclose any quantitative effects on gas readings caused by the interfering gases, as indicated by the gas levels in Table 105.

Compliance shall be checked by inspection of the instructions for use

Table 105 — Test gas levels of interfering gases and vapours

Gas levels in % volume fraction

Gas or vapour Gas level

Metered dose inhaler propellants Specified by the manufacturer

The manufacturer specifies the use of Ethanol, Isopropanol, Acetone, and Methane, with test gas levels required to be within ± 20% of the specified level This applies specifically when the gases are intended for use with inhalation halogenated agents, Xenon, or Helium.

The rate of leakage from the sensor of a non-diverting respiratory gas monitor shall not be greater than

10 ml/min at a pressure of 6 kPa (60 cmH 2 O)

Compliance shall be checked by using a pressure gauge having a measurement accuracy to within ± 0,3 kPa (3 cmH 2 O) and a flowrate metering device having a measurement accuracy to within ± 2 ml/min

Assemble the RGM to install the sensor in a suitable port of the test apparatus, which includes an inlet fitting for a test gas and an air-flowrate metering device Connect a pressure gauge to a third port of the apparatus Gradually adjust the flowrate to achieve a pressure of 6 kPa (60 cmH₂O) in the test apparatus, and determine the flowrate required to maintain this pressure.

101.3* Exhaust port connector for diverting respiratory gas monitor

A diverting respiratory gas monitor shall not be equipped with an exhaust port connector that connects with a connector complying with ISO 594-2

Compliance shall be checked by inspection

A respiratory gas monitor must include a feature that alerts users when the flow rate through the sampling tube drops below the specified value for normal operation, as outlined in the instructions for use.

Compliance shall be checked by functional testing

It shall not be possible to reverse the direction of flow through the sampling tube in a diverting respiratory gas monitor

Compliance shall be checked by inspection and functional testing

IEC 60601-1-8:2003 applies, except as follows

Amendment (add after the note):

NOTE For the purposes of this International Standard, minimum alveolar concentration (MAC) values are those listed in the drug package insert for each inhalational agent

An RGM must be equipped to detect alarm conditions for each respiratory gas it monitors, ensuring that each gas reading is prioritized according to the specifications outlined in Table 106.

The RGM can detect multiple halogenated anaesthetic agents in a gas mixture but cannot quantify their levels or display readings In such cases, it will trigger a medium priority alarm signal.

The RGM must detect, quantify, and display halogenated agent mixtures It should generate a low priority alarm for mixtures below three MAC and a medium priority alarm for those at or above three MAC.

Table 106 — RGM alarm condition priorities

Gas Alarm condition priority for low gas level

Alarm condition priority for high gas level

1 Inspired halogenated anaesthetic agent low priority a medium priority

2 Exhaled CO 2 medium priority medium priority

4 Inspired nitrous oxide low priority a medium priority a

5 Inspired O 2 medium priority medium priority a

7 Multiple halogenated anaesthetic agents present b medium priority

8 Multiple halogenated anaesthetic agents value < 3 MAC c low priority

9 Multiple halogenated anaesthetic agents value > 3 MAC c medium priority NOTE 1 The priorities listed are the minimum priority

Exhaled gas level alarm conditions may be included as an optional feature The RGM can either detect halogenated anesthetic agents without quantifying or displaying their levels, or it can detect, quantify, and display the mixture of these agents effectively.

Table 107 — Examples of minimum alveolar concentration (MAC) values

% volume fraction Halothane 0,77 Enflurane 1,7 Isoflurane 1,15

(25-year-old patient) Sevoflurane 2,1 Nitrous oxide 105 a

At the time of this International Standard's publication, the MAC values listed in the table reflect those provided by the U.S Food and Drug Administration for a healthy adult male patient aged 40 years.

Other MAC values may be used MAC values may be determined by algorithms

See also 6.8.2 cc) viii) a 1 MAC nitrous oxide can only be reached in a hyperbaric chamber

201.2 Disclosures for intelligent alarm system

Amendment (add as the last sentence in the subclause before the compliance test):

If the alarm system has a means to change alarm condition priority, without operator intervention, it shall not allow a change to a priority lower than that specified in this International Standard

Amendment (add as the last sentence in the subclause before the compliance test):

Means shall be provided to prevent the low alarm limit of the inspired oxygen gas reading of an RGM from being set below 18 % in an alarm preset

Each gas reading alarm condition in the RGM must have adjustable alarm limits, except for the high gas level of inspired nitrous oxide, which is exempt from this rule.

Deliberate action shall be required on the part of the operator to adjust alarm limits

Compliance shall be checked by inspection

201.6.2.102 Low alarm limit of the oxygen gas reading

It shall not be possible to set the low alarm limit of the inspired oxygen gas reading below 18 %

Compliance shall be checked by inspection

Amendment (add at the end of the second paragraph):

Means shall be provided to prevent unintentional activation of audio off and alarm off

Amendment (add at the end of the third paragraph):

The manufacturer-configured alarm preset for the audio-paused or alarm-paused interval shall be no greater than 2 min

The Appendices of IEC 60601-1:1988 apply

Addition: The subsequent annexes form an additional element of this part of ISO 10651

This annex explains the reasoning behind certain requirements of this International Standard, targeting individuals who are knowledgeable about the subject but were not involved in its creation Understanding this rationale is crucial for the effective application of the requirements Additionally, as clinical practices and technologies evolve, this rationale will aid in revising the International Standard to accommodate these changes.

The numbering of the following rationale corresponds to the numbering of the clauses in this International Standard The numbering is, therefore, not consecutive

Research-grade RGMs are typically experimental and designed for non-medical applications Applying the standards of this International Standard to research RGMs could hinder the advancement of innovative techniques and designs.

The Minimum Alveolar Concentration (MAC) can differ based on a patient's age, necessitating that the operator provides the patient's age to the RGM This allows the RGM to appropriately adjust the MAC threshold according to the patient's specific age-related needs.

AA.6.8.2 Test method for legibility

The Minimum Angle of Resolution (MAR) is a refined method for measuring visual acuity, enhancing the traditional Snellen scale MAR values are expressed as a logarithm, known as Log MAR, which can be derived from the Snellen scale; for instance, Log MAR equals log(6/6), resulting in a value of 0 for normal vision.

Understanding the fundamental operations and principles of the RGM, along with its detailed specifications, is crucial; however, this information is often lacking in the user instructions.

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