equipment which can be touched without the use of a tool.
Accessible Metal Part
Metal part of equipment
which can be touched without the use of a tool.
Shortest path in air between two conductive parts.
A part of the
equipment which in normal use:
patient for the equipment to perform its function; or
can be brought into contact with the patient; or
needs to be touched by the patient
- necessarily comes into physical contact with the
Insulation applied to live parts to provide basic protection against electric shock.
Class I EquipmentEquipment in which protection against electric shock does not rely on
only, but which includes an additional safety precaution in that means are provided for the connection of the equipment to the protective earth conductor in the fixed wiring of the installation in such a way that
accessible metal parts
cannot become live
in the event of a failure of basic insulation.
Class II Equipment
in which protection against electric shock does not rely on basic insulation only, but which additional safety precautions such as double insulation or reinforced insulation
are provided, there being no provision for protective earthing or reliance upon installation conditions.
Shortest path along the surface of insulating material
between two conductive parts.
Insulation comprising both
basic insulation and
Earth Leakage Current
Current Flowing from the mains
part through or across the insulation into the protective earth conductor.
Exterior surface of the equipment including:
accessible metal parts
, knobs, grips and the like;
for the purpose of tests, metal foil, with specified dimensions, applied in contact with parts of the external surface made of material with low conductivity or made on insulating
Enclosure Leakage Current
Current flowing from the enclosure, or parts thereof, excluding applied parts
, accessible to the operator or patient in normal use, through an external conductive connection other than the protective earth conductor to earth or to another part of the enclosure.
Functional Earth Conductor
Conductor to be connected to a functional earth terminal.
Functional Earth Terminal
Terminal directly connected to a point of a measuring supply or control circuit or to a
screening part which is intended to be earthed for functional purposes.
Current that is not functional. The following leakage currents are defined: Earth Leakage Current
, Enclosure Leakage Current
, and Patient Leakage Current
State of a part which, when connection is made to that part, can cause a current exceeding the allowable leakage current
for the part concerned to flow from that part to earth or from that part to an accessible part
of the same equipment
Entirety of all parts of the equipment intended to have a conductive connection with the supply mains
. For the purpose of this definition, the protective earth conductor is not considered as a part of the mains part.
Medical Electrical Equipment
Electrical equipment, provided with no more than one connection to a particular supply mains and intended to diagnose, treat or monitor the patient
under medical supervision and which makes physical or electrical contact with the patient and/or transfers energy to or from the patient and/or detects such energy transfer to or from the patient. The equipment includes those accessories as
defined by the manufacturer which are necessary to enable the normal use of the equipment.
Living being (person or animal) undergoing
medical or dental investigation or treatment.
Patient Auxiliary Current
Current flowing in the patient in normal use between part of the applied part
and not intended to produce a physiological effect, for example, bias current of an amplifier, current used in impedance plethysmography.
Patient Leakage Current
Current flowing from the applied part via the patient to earth or flowing from the patient
via an F-Type applied part to earth originating from the unintended appearance of a voltage from an external source on the patient.
Potential Equalization Conductor
Conductor providing a connection between equipment and the potential equalization busbar of the electrical installation.
Protective Earth Conductor
Conductor to be connected between the
protective earth terminal and an external protective earthing system.
Protective Earth Terminal
Terminal connected to conductive parts of Class I equipment for safety purposes. This terminal is intended to be connected to an external earthing system by a protective earth conductor.
Single insulation system applied to live
parts which provide a degree of protection against electric shock equivalent to double insulation
under the conditions specified in IEC 60601-1.
In dependent insulation applied in addition to basic insulation in order to provide protection against electric shock in the event of a failure of basic insulation.
Permanently installed power source which
may also be used to supply electrical apparatus which is outside the scope of IEC 60601-1.
Extra-corporeal object (e.g. screwdriver) which may be used to
secure or release fasteners or to make adjustments.
Authority responsible for the use and maintenance of equipment.