Saturday, July 16, 2022

IEC 60601-1 Leakage Currents and Patient Auxiliary Currents

Hi friends!!!


In our previous blogs, we have discussed about the following topics.


IEC 60601-1 Definitions


IEC 60601-1 Classification of Medical Electrical Equipment


IEC 60601-1 General Requirements for Testing Medical Electrical Equipment


IEC 60601-1 Medical Electrical Systems


IEC 60601-1 Protection against unwanted and excessive radiation hazards


IEC 60601-1 General Requirements


IEC 60601-1 Programmable Electrical Medical Systems 


IEC 60601-1 Hazardous situations and fault condition


IEC 60601-1 Construction of Medical Electrical Equipment


EU MDR Assessment Routes


EU MDR Timeline, Annex, Chapter


EU MDR Post Market Surveillance


EU MDR Clinical Evaluation


EU MDR Technical Documentation - Part 1


EU MDR Technical Documentation - Part 2


EU MDR General Safety and Performance Requirement


EU MDR Information on the Label


EU MDR Post Market Clinical Follow Up


EU MDR Unique Device Identification - Part 1 


EU MDR Unique Device Identification - Part 2


EU MDR Classification Rules


EU MDR EUDAMED


EU MDR Economic Operators


EU MDR Chapter & Articles - Part 1


EU MDR Chapter & Articles - Part 2


In today's blog, we are going to discuss about IEC 60601-1.


IEC 60601-1 states the Basic safety requirements for Medical Electrical Equipment's. Satisfying the requirements of IEC 60601-1 is an important task in order to commercialize the Medical Electrical Equipment's


Therefore, it is important for Medical Device QA/RA Professionals to know in detail about Sub Clause 8.7: Leakage Current and Patient Auxiliary Currents as per IEC 60601-1.


Let's get into the topic.


Sub Clause 8.7: Leakage Currents and Patient


Auxiliary Currents


The Sub Clause 8.7 of IEC 60601-1 states the requirements for Leakage Currents and Patient Auxiliary Current. It is further classified as following.


General Requirements

Single Fault Conditions

Allowable Values

Measurements

 

Let’s discuss in detail about the important requirements of above-mentioned Sub Clause.

IEC 60601-1 Discusses about the following types of Current.

 

Touch Current:

The Touch Current is the amount of current that flows through a person when they touches one or more accessible parts of the Medical Electrical Equipment.


Earth Leakage Current:

The Earth Leakage Current is an electric current that flows into the Protective Earth Conductor through or via the insulation of the Medical Device.


Patient Auxiliary Current:

The Patient Auxiliary Current is an electric current which flows from one part of applied part to another part of applied part through the patient.


Patient Leakage Current:

The Patient Leakage Current is a leakage current which flows through the patient who is connected to a applied part or parts to the earth.


 

Allowable Values

 

The Protection against electric shock shall be provided by Electrical Isolation. The Electrical Isolation shall have a quality such that the current flowing through it shall be limited to the values specified in Clause 8.7.3 Allowable Values of IEC 60601-1.


The Below mentioned Allowable values shall be applicable in Single Fault Conditions mentioned in IEC 60601-1.


For Touch Current, the allowable value under Normal Condition is 100 μA and the allowable value under Single Fault Condition is 500 μA.


For Earth Leakage Current, the allowable value under Normal Condition is 5 mA and the allowable value under Single Fault Condition is 10 mA.

 

The Higher value of Earth Leakage Current is allowed for Medical Electrical Equipment which are permanently installed and are connected to supply circuit which supplies only this Medical Electrical Equipment.

 

The Allowable value for Patient Leakage Current & Patient Auxiliary Current shall be as per the requirements stated in Table 3 & 4 of IEC 60601-1


 

Measurements

 

General:

 

The Medical Electrical Equipment shall be in an operating temperature before measuring the Touch Current, Earth Leakage Current, Patient Auxiliary Current, Patient Leakage Current.

 

The Number of Tests shall be reduced when there is no possibility of any hazardous situations based on the arrangement of components and materials of Medical Electrical Equipment and examination of circuit arrangement.

 

Measuring Supply Circuits:

 

The Medical Electrical Equipment shall be connected to an appropriate power source when it is specified for connection to a Supply Mains.

 

The Medical Electrical Equipment which is supposed to be internally powered is tested without any connection to measuring supply circuit.

 

Connection to a Measuring Supply Circuits:

 

The Medical Electrical Equipment is tested while connected to the Measuring Supply Circuit when it is provided with an appliance inlet. In this case, the Medical Electrical Equipment is connected to Measuring Supply Circuit via detachable power cord of Length & Type as per the requirements of IEC 60601-1.

 

The Permanently Installed Medical Electrical Equipment is also tested while connected to the Measuring Supply Circuit.

 

Measurement of Touch Current, Patient Leakage Current & Patient Auxiliary Current:

 

The Circuit represented in Figure 14 – Figure 20 of IEC 60601-1 shall be used in the Measurement of Touch Current, Patient Leakage Current & Patient Auxiliary Current.

 

Multiple Patient Connection:

 

When there are Multiple Patient connections in a Medical Electrical Equipment, it is investigated to ensure that the allowable values do not exceed for Leakage Current and Patient Auxiliary Current when one or more patient connections are disconnected from the patient or disconnected from the patient and earthed.


Now I hope you have acquired some knowledge about IEC 60601-1 Sub Clause 8.7: Leakage Current and Patient Auxiliary Currents. We will meet again with another valuable topic related to Biomedical Engineering, Medical Device, Healthcare.


NOTE: Dear friends!!!... Please do comment a topic related to Biomedical, so that we can discuss it in future blogs.


Check out for this blog about Computed Tomography,  X ray, MRI scan, ECG.


Generations of CT Scanners


COMPUTED TOMOGRAPHY|TECHNOLOGY|ARTIFACTS


x ray machine working principle


components of x ray tube


MRI scan 


MRI With Contrast


Brain MRI


Types of MRI scanners


ELECTROCARDIOGRAM


12 Lead ECG Placement


HOW TO READ AN ECG


Holter Monitor


DON’T FORGET TO FOLLOW THIS BLOG PAGE


DROP YOUR MAIL ID TO GET IMMEDIATE UPDATES


If you find this blog post knowledgeable, 

comment & share it with a friend! 


 

Thursday, June 23, 2022

IEC 60601-1 Construction of Medical Electrical Equipment

Hi friends!!!


In our previous blogs, we have discussed about the following topics.


IEC 60601-1 Definitions


IEC 60601-1 Classification of Medical Electrical Equipment


IEC 60601-1 General Requirements for Testing Medical Electrical Equipment


IEC 60601-1 Medical Electrical Systems


IEC 60601-1 Protection against unwanted and excessive radiation hazards


IEC 60601-1 General Requirements


IEC 60601-1 Programmable Electrical Medical Systems 


IEC 60601-1 Hazardous situations and fault condition


EU MDR Assessment Routes


EU MDR Timeline, Annex, Chapter


EU MDR Post Market Surveillance


EU MDR Clinical Evaluation


EU MDR Technical Documentation - Part 1


EU MDR Technical Documentation - Part 2


EU MDR General Safety and Performance Requirement


EU MDR Information on the Label


EU MDR Post Market Clinical Follow Up


EU MDR Unique Device Identification - Part 1 


EU MDR Unique Device Identification - Part 2


EU MDR Classification Rules


EU MDR EUDAMED


EU MDR Economic Operators


EU MDR Chapter & Articles - Part 1


EU MDR Chapter & Articles - Part 2


In today's blog, we are going to discuss about IEC 60601-1.


IEC 60601-1 states the Basic safety requirements for Medical Electrical Equipment's. Satisfying the requirements of IEC 60601-1 is an important task in order to commercialize the Medical Electrical Equipment's


Therefore, it is important for Medical Device QA/RA Professionals to know in detail about Clause 15: Construction of Medical Electrical Equipment as per IEC 60601-1.


Let's get into the topic.


Clause 15 - Construction of Medical Electrical

Equipment

 

The Clause 15 of IEC 60601-1 states the requirements for Construction of Medical Electrical Equipment. The following are the Sub-Clauses.


Arrangements of controls and indicators of Medical Electrical Equipment 

Serviceability

Mechanical strength

Medical Electrical Equipment components and general assembly

Mains Supply Transformers of Medical Electrical Equipment and transformers providing separation 

 

Let’s discuss in detail about Important requirements of above-mentioned Sub Clauses.

Serviceability:

The Parts of Medical Electrical Equipment which are likely to be replaced or adjusted due to electrical, mechanical wear and environmental degradation or ageing shall be located and secured in an appropriate position which allows inspection, servicing, replacement and adjustment without damage to the nearby parts or wiring.

 

Mechanical Strength:

The Medical Electrical Equipment or its parts shall have an adequate mechanical strength which prevents it from having a loss of basic safety and essential performance. The adequacy of Mechanical strength is determined by the application of following tests based on the Medical Electrical Equipment Type.


Hand-Held Type 

Push Test

Drop Test

Molding stress relief Test

 

Body Worn & Portable Type

Push Test

Impact Test

Drop Test

Molding stress relief Test


Mobile Type

Push Test

Impact Test

Rough handling Test

Molding stress relief Test


Fixed or Stationary Type 

Push Test

Impact Test

Molding stress relief Test


Medical Electrical Equipment components and general

assembly:

 

Construction of connectors

The Connectors of Medical Electrical Equipment shall be designed in such a way that the incorrect connection of accessible connectors and the removal of connectors without the use of tool shall be prevented.


Temperature and overload control devices

Over current releases and thermal cuts outs shall be independent and non-Self resetting.

 

Batteries

The incorrect polarity of the battery connection shall be prevented. The housing of the battery shall be properly ventilated to allow gases which produced due to charging and discharging of batteries to pass through.

 

Indicator

There shall be indicator lights to indicate that the Medical Electrical Equipment is ready for normal use. There shall be an indicator to indicate that the output exists for the Medical Electrical Equipment, in cases where the accidental or prolonged operation of output circuit might lead to a hazardous situation.


Actuating parts of controls of Medical Electrical Equipment

All actuating parts of the Medical Electrical Equipment shall be adequately secured such that they cannot work loose or pulled off during the normal use. All rotating or movable parts of controls in Medical Electrical Equipment shall be provided with stops of adequate mechanical strength to prevent it changing from Maximum controlled parameter to Minimum controlled parameter or vice versa.

 

Cord-connected Hand-Held and foot-operated control devices

When placed in an abnormal position, the Hand-Held and foot-operated control devices shall not present any unacceptable risk due to change in their controlled settings. The foot operated control devices shall be designed in a manner to support and withstand the weight of a adult human.

 

Mains Supply Transformers of Medical Electrical Equipment

and transformers providing separation:

 

In the event of short circuit or overload of any output winding, the transformers of Medical Electrical Equipment shall be protected from Short Circuit & Overload. The transformers shall undergo short circuit Test, Overload Test & Dielectric Strength test as per the requirements of IEC 60601-1.


Now I hope you have acquired some knowledge about IEC 60601-1 Clause 15: Construction of  Medical Electrical EquipmentWe will meet again with another valuable topic related to Biomedical Engineering, Medical Device, Healthcare.


NOTE: Dear friends!!!... Please do comment a topic related to Biomedical, so that we can discuss it in future blogs.


Check out for this blog about Computed Tomography,  X ray, MRI scan, ECG.


Generations of CT Scanners


COMPUTED TOMOGRAPHY|TECHNOLOGY|ARTIFACTS


x ray machine working principle


components of x ray tube


MRI scan 


MRI With Contrast


Brain MRI


Types of MRI scanners


ELECTROCARDIOGRAM


12 Lead ECG Placement


HOW TO READ AN ECG


Holter Monitor


DON’T FORGET TO FOLLOW THIS BLOG PAGE


DROP YOUR MAIL ID TO GET IMMEDIATE UPDATES


If you find this blog post knowledgeable, 

comment & share it with a friend! 


 

Monday, June 6, 2022

IEC 60601-1 Hazardous situations and fault condition

Hi friends!!!


In our previous blogs, we have discussed about the following topics.


IEC 60601-1 Definitions


IEC 60601-1 Classification of Medical Electrical Equipment


IEC 60601-1 General Requirements for Testing Medical Electrical Equipment


IEC 60601-1 Medical Electrical Systems


IEC 60601-1 Protection against unwanted and excessive radiation hazards


IEC 60601-1 General Requirements


IEC 60601-1 Programmable Electrical Medical Systems 


EU MDR Assessment Routes


EU MDR Timeline, Annex, Chapter


EU MDR Post Market Surveillance


EU MDR Clinical Evaluation


EU MDR Technical Documentation - Part 1


EU MDR Technical Documentation - Part 2


EU MDR General Safety and Performance Requirement


EU MDR Information on the Label


EU MDR Post Market Clinical Follow Up


EU MDR Unique Device Identification - Part 1 


EU MDR Unique Device Identification - Part 2


EU MDR Classification Rules


EU MDR EUDAMED


EU MDR Economic Operators


EU MDR Chapter & Articles - Part 1


EU MDR Chapter & Articles - Part 2


In today's blog, we are going to discuss about IEC 60601-1.


IEC 60601-1 states the Basic safety requirements for Medical Electrical Equipment's. Satisfying the requirements of IEC 60601-1 is an important task in order to commercialize the Medical Electrical Equipment's


Therefore, it is important for Medical Device QA/RA Professionals to know in detail about Clause 13: Hazardous situations and fault conditions for Medical Electrical Equipment as per IEC 60601-1.


Let's get into the topic.


Clause 13 – Hazardous Situations and fault

conditions for Medical Electrical Equipment


The Clause 13 of IEC 60601-1 states the requirements of Hazardous situations and fault conditions for Medical Electrical Equipment. The following are the Sub-Clauses.

 

  1. Specific Hazardous Situations
  2. Single Fault Conditions


Specific Hazardous Situations:

The Specific Hazardous Situations shall be further classified as following.

 

Deformation of enclosure, Emissions or exceeding maximum temperature:

The following Hazardous Situations shall not occur:


1. The Emission of molten metal, flames, poisonous or ignitable substances in hazardous quantities. 

2. The deformation of Enclosures shall not occur to an extent which can cause a non-compliance with requirements in IEC 60601-1.

3. The Temperatures of Applied Parts shall not exceed the allowed values.

4. The Temperatures of Medical Electrical Equipment parts other than Applied Parts which are likely to be touched shall not exceed the allowed values.

5. The Temperatures of Accessible Parts which are likely to be touched but are not supposed to be touched to operate the Medical Electrical Equipment shall not exceed the allowed values.

6. The Temperatures of Accessible Parts which are supposed to be touched to operate the Medical Electrical Equipment shall the exceed the allowed values mentioned.

 

Exceeding Leakage Current or voltage limits:

The following Hazardous Situations shall not occur:


1. The allowed limits for leakage current in Single Fault Condition shall not exceed.

2. The allowed voltage limits for Applied Parts and Accessible Parts shall not exceed.

Single Fault Conditions:

During the application of the Single Fault Conditions listed below, the Normal Conditions identified as per IEC 60601-1 shall also be applied in the least favorable combination.

 

The Single Fault Conditions are as following:

 

1.    Electrical Single Fault Condition

2.    Overheating of transformers in Medical Electrical Equipment

3.    Failure of Thermostats

4.    Failure of temperature limiting devices


5.    Leakage of Liquid


The Medical Electrical Equipment shall be constructed in such a way when there is a liquid leakage during a Single Fault Condition, only a small amount of liquid leaks. The sealed rechargeable batteries are exempted from this requirement.


6.    Impairment of cooling that could result in a Hazardous Situation


The following are few of examples related to Impairments of cooling that can occur: 

The consecutive locking of single ventilation fans.

The covering of ventilation openings in top and sides of the enclosure or the Medical Electrical  Equipment’s are placed against the walls.

The blockage of filters.

Interruption in the flow of cooling agent.


7.    Locking of Movable Parts


In Medical Electrical Equipment, the moving parts are locked if it has moving Accessible Parts or Applied Parts which are liable to be jammed or liable to be operated when unattended (this includes automatically or remotely controlled Medical Electrical Equipment), or it has one or more motors with a locked rotor torque smaller than the full load torque.

If Medical Electrical Equipment has more than one moving part as described above, only one moving part is locked at a time. If multiple motors can. be locked in a Single Fault Condition, then all motors are locked simultaneously


8.    Interruption and short circuiting of motor capacitors

9.    Additional test criteria for motor operated Medical Electrical Equipment

10.  Failures of components in Medical Electrical Equipment used in conjunction with Oxygen Rich Environments

11.   Failure of parts that might result in a Mechanical Hazard

12.    Overload


Now I hope you have acquired some knowledge about IEC 60601-1 Clause 13: Hazardous situations and fault conditions for Medical Electrical EquipmentWe will meet again with another valuable topic related to Biomedical Engineering, Medical Device, Healthcare.


NOTE: Dear friends!!!... Please do comment a topic related to Biomedical, so that we can discuss it in future blogs.


Check out for this blog about Computed Tomography,  X ray, MRI scan, ECG.


Generations of CT Scanners


COMPUTED TOMOGRAPHY|TECHNOLOGY|ARTIFACTS


x ray machine working principle


components of x ray tube


MRI scan 


MRI With Contrast


Brain MRI


Types of MRI scanners


ELECTROCARDIOGRAM


12 Lead ECG Placement


HOW TO READ AN ECG


Holter Monitor


DON’T FORGET TO FOLLOW THIS BLOG PAGE


DROP YOUR MAIL ID TO GET IMMEDIATE UPDATES


If you find this blog post knowledgeable, 

comment & share it with a friend!