-
GHTF/SG1/N77:2012
FINAL
DOCUMENT
Global
Harmonization Task Force
(Revision of
GHTF/SG1/N15:2006)
Title:
Principles of Medical Devices
Classification
Authoring
Group:
Study Group 1 of the Global
Harmonization Task Force
Endorsed by:
The Global
Harmonization Task Force
Date:
November
2
nd
, 2012
Dr. Kazunari
Asanuma, GHTF Chair
This
document
was
produced
by
the
Global
Harmonization
Task
Force,
a
voluntary
international
group
of
representatives
from
medical
device
regulatory
authorities
and
trade
associations
from
Europe, the United States of America
(USA), Canada, Japan and Australia.
The
document
is
intended
to
provide
non-binding
guidance
to
regulatory
authorities
for
use
in
the
regulation of medical
devices, and has been subject to consultation
throughout its development.
There
are
no
restrictions
on
the
reproduction,
distribution
or
use
of
this
document;
however,
incorporation of this document, in part
or in whole, into any other document, or its
translation into
languages other than
English, does not convey or represent an
endorsement of any kind by the Global
Harmonization Task Force.
Copyright ? 2012 by the Global
Harmonization Task Force
Principles of
Medical Devices Classification
Study
Group 1 Final Document GHTF/SG1/N77:2012
Table of Contents
1.0
Introduction
.
...
..................................................
..................................................
...........
4
2.0
Rationale,
Purpose and Scope
.
.........
..................................................
..........................
5
2.1
Rationale ...
..................................................
..................................................
..................
5
2.2
Purpose
.
................................
..................................................
.........................................
5
2.3
Scope
......................
..................................................
..................................................
.....
5
3.0
References
.
.............................
..................................................
......................................
5
4.0
Definitions
.
....
..................................................
..................................................
.............
6
5.0
General
Principles
.
................
..................................................
......................................
8
6.0
Classification System for Medical
Devices ..........................................
.......................
9
6.1
Structure of
the Classification Rules
.
..
..................................................
..........................
9
6.2
Diagrammatic
Representation of the Classification System
.
.................................
.......
1
0
6.3
Manufacturer?s Determination of Device
Class
.
..........
.................................................
1
2
7.0
Classification Rules
.
.............................................
..................................................
.....
1
2
7.1
Non-Invasive
Devices ..........................................
..................................................
.......
1
2
7.2
Invasive
Devices ..........................................
..................................................
...............
1
4
7.3
Active
Devices ..........................................
..................................................
..................
1
8
7.4
Additional
Rules ............................................
..................................................
.............
2
1
7.5
Rationale for
the inclusion of the Additional Rules within this
document
...................
2
2
8.0
Reclassification of Medical Devices
.
..............................
............................................
2
3
Appendix A: Decision trees to
illustrate how the rules may be used to classify
specific
devices.
.
................................................ .................................................. ..............................
2
4
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Principles of Medical Devices
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Study Group 1 Final
Document GHTF/SG1/N77:2012
Preface
The document herein
was produced by the Global Harmonization Task
Force, a
voluntary group of
representatives from medical device Regulatory
Authorities and the
regulated industry.
The document is intended to provide non-binding
guidance for use in the
regulation of
medical devices, and has been subject to
consultation throughout its development.
There are no restrictions on the
reproduction, distribution, translation or use of
this
document. However, incorporation
of this document, in part or in whole, into any
other
document does not convey or
represent an endorsement of any kind by the Global
Harmonization Task Force.
November 2
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,
2012
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Principles of Medical Devices
Classification
Study Group 1 Final
Document GHTF/SG1/N77:2012
1.0
Introduction
The primary way in which the GHTF
achieves its goals is through the production of a
series of guidance documents that
together describe a global regulatory model for
medical
devices. The purpose of such
guidance is to harmonize the documentation and
procedures that
are used to assess
whether a medical device conforms to the
regulations that apply in each
jurisdiction. Eliminating differences
between jurisdictions decreases the cost of
gaining
regulatory compliance and
allows patients earlier access to new technologies
and treatments.
This document has
been developed to encourage and support global
convergence of
regulatory systems. It
is intended for use by Regulatory Authorities
(RAs), Conformity
Assessment Bodies
(CABs) and industry, and will provide benefits in
establishing, in a
consistent way, an
economic and effective approach to the control of
medical devices in the
interest of
public health. It seeks to strike a balance
between the responsibilities of RAs to
safeguard the health of their citizens
and their obligations to avoid placing unnecessary
burdens
upon the regulated industry.
This document should be read in
conjunction with the GHTF document entitled
Principles of Conformity Assessment for
Medical Devices
that prescribes
conformity
assessment requirements
appropriate to each of the four classes proposed
herein. The link
between device
classification and conformity assessment is
fundamental to the development of
an
effective global regulatory model. If such is
adopted in a consistent manner by all
jurisdictions, the goal of a premarket
approval for a particular device being accepted
globally,
may be achieved.
This document
supersedes
GHTF/SG1/N15:2006
which provided guidance on the
same
topic. It has been modified to:
?
clarify the
basis of allocating medical devices to one of four
classes;
?
change
the rule applying to sterilisation and
disinfection devices;
?
remove the inconsistency with
GHTF/SG1/N011
Summary Technical
Documentation for Demonstrating
Conformity to the Essential Principles of
Safety and Performance of Medical
Devices (STED)
;
?
add a Section
on the reclassification of medical devices; and
?
incorporate
changes resulting from the public scrutiny
process.
Where other guidance
documents within the series are referenced within
this text, their
titles are italicised
for clarity.
Study Group 1 of the
Global Harmonization Task Force (GHTF) has
prepared this
guidance document.
Comments or questions about it should be directed
to either the Chair or
Secretary of
GHTF Study Group 1 whose contact details may be
found on the GHTF website
1
.
1
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Principles of Medical
Devices Classification
Study Group 1
Final Document GHTF/SG1/N77:2012
2.0
Rationale,
Purpose and Scope
2.1
Rationale
It is widely
accepted that there should be a method to separate
medical devices into a
small number of
groups, or classes, and subsequently apply
different conformity assessment
techniques to each class. The global
adoption of a rules-based classification procedure
would
offer significant benefits to
manufacturers, users, patients, and RAs and
support global
convergence of
regulatory systems.
2.2
Purpose
To stipulate a
series of principles and rules that allow a
medical device to be assigned to
one of
four classes based on its intended use, and
thereby:
?
assist a manufacturer to allocate its
medical device to an appropriate class using
a set of classification rules; and
?
allow RAs to
pronounce upon matters of interpretation for a
particular medical
device, when
required so to do.
Subsequently,
such classification will determine the conformity
assessment procedures
that will be
applied to the device.
This document
is intended for use by RAs, CABs and the regulated
Industry,
2.3
Scope
This document applies
to all products that fall within the definition of
the term
?
medical
device
?
,
other
than
IVD medical devices,
for which a separate classification document is
available on the GHTF website.
3.0
References
2
GHTF/SG1/N44:2008
Role of
Standards in the Assessment of Medical Devices.
GHTF/SG1/N68:2012
Essential
Principles of Safety and Performance of Medical
Devices.
GHTF/SG1/N70:2011
Label and Instructions for Use for Medical
Devices.
GHTF/SG1/N071:2012
Definition of the Terms
‘Medical
Device’
and ‘In Vitro
Diagnostic
(IVD) Medical
Device’
.
GHTF/SG1/N78:2012
Principles of Conformity Assessment
for Medical Devices.
2
The listed documents are
subject to periodic review and may be superseded
by later versions. The reader is
encouraged to refer to the GHTF website
to confirm whether the referenced documents remain
current.
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4.0
Definitions
Accessory to a medical device:
Means an article intended
specifically by its manufacturer to be
used together a particular medical
device to enable or assist that device to be used
in
accordance with its intended use.
Active medical device:
Any
medical device, operation of which depends on a
source of electrical
energy or any
source of power other than that directly generated
by the human body or
gravity and which
acts by converting this energy. Medical devices
intended to transmit
energy, substances
or other elements between an active medical device
and the patient,
without any
significant change, are not considered to be
active medical devices.
Standalone
software is considered to be an active medical
device.
Active therapeutic device:
Any active medical device, whether used
alone or in combination
with other
medical devices, to support, modify, replace or
restore biological functions or
structures with a view to treatment or
alleviation of an illness or injury.
Active device intended for diagnosis:
Any active medical device, whether used
alone or in
combination with other
medical devices, to supply information for
detecting, diagnosing,
monitoring or
treating physiological conditions, states of
health, illnesses or congenital
deformities.
Central
circulatory system:
The major internal
blood vessels including the following:
pulmonary veins, pulmonary arteries,
cardiac veins, coronary arteries, carotid arteries
(common, internal and external),
cerebral arteries, brachiocephalic artery, aorta
(includes all segments of the aorta),
inferior and superior vena cava and common iliac
arteries.
Central nervous
system:
The brain, meninges, and
spinal cord.
Cleaning:
Removal of contamination from an item to the
extent necessary for its further
processing and its intended subsequent
use.
Disinfection:
Reduction of the number of viable
microorganisms on a product to a level
previously specified as appropriate for
its intended further handling or use.
Duration of use
Transient:
Normally
intended for continuous use for less than 60
minutes.
Short term:
Normally intended for continuous use
for between 60 minutes and 30 days.
Long term:
N
ormally intended for
continuous use for more than 30 days.
NOTE: continuous use means:
a) The entire duration of use of the same device
without regard to temporary
interruption of use during a procedure
or, temporary removal for purposes such as
cleaning or disinfection of the device.
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b) The accumulated use of a device that
is intended by the manufacturer to be
replaced immediately with another of
the same type.
Harm:
Physical injury or damage to the health
of people or damage to property or the
environment.
Hazard:
Potential source of harm.
Intended use / Intended
purpose:
The objective intent of the
manufacturer regarding the use
of a
product, process or service as reflected in the
specifications, instructions and
information provided by the
manufacturer.
Invasive devices
Invasive device:
A device,
which, in whole or in part, penetrates inside the
body, either
through a body orifice or
through the surface of the body.
Body
orifice:
Any natural opening in the
body, as well as the external surface of the
eyeball, or any permanent artificial
opening, such as a stoma or permanent tracheotomy.
Surgically invasive device:
(a) An invasive device which penetrates
inside the body through the surface of the
body, with the aid or in the context of
a surgical operation.
(b) A medical
device which produces penetration other than
through a body orifice
.
I
mplantable device:
Any device, including those that are
partially or wholly absorbed,
which is
intended: -
?
to
be totally introduced into the human body or,
?
to replace an
epithelial surface or the surface of the eye,
by surgical
intervention which is intended to remain in place
after the procedure.
Any device
intended to be partially introduced into the human
body through surgical
intervention and
intended to remain in place after the procedure
for at least 30 days is also
considered
an implantable device.
Lay
person
: Individual that does not have
formal training in a relevant field or
discipline
.
Life supporting
or life sustaining:
A device that is
essential to, or that yields information that
is essential to, the restoration or
continuation of a bodily function important to the
continuation of human life.
Medical device:
See
GHTF guidance
document:
Definition of the Term
‘
Medical
Device
’
.
Reusable medical device:
Means a device intended for repeated use either on
the same or
different patients, with
appropriate decontamination and other reprocessing
between
uses.
Reusable
surgical instrument:
Instrument
intended for surgical use by cutting, drilling,
sawing, scratching, scraping, clamping,
retracting, clipping or similar surgical
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procedures, without connection to any
active medical device and which are intended by
the manufacturer to be reused after
appropriate procedures for cleaning and/or
sterilisation have been carried out.
Risk:
Combination of the
probability of occurrence of harm and the severity
of that harm.
Sterilisation:
Validated
process used to render product free from viable
microorganisms.
NOTE: In a
sterilisation process, the nature of microbial
inactivation is exponential and
thus
the survival of a microorganism on an individual
item can be expressed in terms of
probability. While this probability
can be reduced to a very low number, it can never
be reduced to zero.
Vital
physiological process:
Means a process
that is necessary to sustain life, the indicators
of
which may include any one or more of
the following:
?
respiration;
?
heart rate;
?
cerebral function;
?
blood gases;
?
blood pressure;
?
body
temperature.
5.0
General Principles
Manufacturers of medical devices are
subject to regulatory controls overseen by
national RAs. The RA specifies
procedures to be followed by manufacturers during
the design,
manufacture, and marketing
of each device, and describes the manner in which
a manufacturer
should demonstrate
conformity to such procedures. It is widely
accepted that oversight of
these
procedures by the RA should increase in line with
the potential of a medical device to
cause harm to a patient or user (i.e.
the hazard it presents), and to do so without
placing an
unwarranted increase in the
cost of regulatory compliance for either the
manufacturer or RA, or
delay market
entry. In practice, this is best achieved by
assigning every medical device into
one
of four groups
–
or ?classes?
- by applying
the classification rules described in this
guidance document, and specify in
separate guidance
3
the
different conformity assessment
procedures that should apply to each
group of devices.
Customarily, a
classification system of this type is referred to
as a
?
risk-based
classification scheme? but this is a
misnomer since the rules take account only of the
hazard
presented by a particular device
and not the probability harm will
occur
4
.
The RA
takes account of the probability that harm will
occur by modifying the evidence
requirements at the conformity
assessment stage rather than modifying the
classification rules.
Probability of
harm is influenced by factors such as whether:
?
the technology
is regarded as mature;
?
the device type is the source of many
adverse event reports;
3
See
GHTF/SG1/N78:2012
Principles of
Conformity Assessment for Medical
Devices.
4
See the internationally accepted
definition of? risk? in Section 4.0.
Page 8 of 30
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?
the device?s
manufacturer has a long experience of the device
and the
technologies it embodies;
?
the device user
is a lay person.
The hazard presented
by a particular medical device depends
substantially on its
intended use and
the technology it utilises. Consequently, the
classification rules stipulated in
Section 7.0 of this guidance document
take factors into account such as, whether the
device:
?
is
life supporting or sustaining;
?
is invasive and
if so, to what extent and for how long;
?
incorporates
medicinal products, or human/animal tissues/cells;
?
is an active
medical device;
?
delivers medicinal products, energy or
radiation;
?
could modify blood or other body
fluids;
?
is used
in combination with another medical device.
A further advantage of a rules-based
system of classification is that it is easily
adapted
to accommodate new
technologies.
6.0
Classification System for Medical
Devices
6.1
Structure of the Classification Rules
a)
RAs should
establish a device classification system
consisting of four classes where
Class
A represents the lowest hazard and Class D the
highest.
b)
The
determination of class should be based on rules
derived from the potential of a
medical
device to cause harm to a patient or user (i.e.
the hazard it presents) and
thereby on
its intended use and the technology/ies it
utilises.
c)
These rules should allow a manufacturer
to readily identify the class of its particular
medical device subject, where
appropriate, to the RA resolving any matters of
interpretation.
d)
The rules
should be capable of accommodating future
technological developments.
e)
The
manufacturer should document its justification for
placing its product into a
particular
class, including the resolution of any matters of
interpretation where it has
asked a RA
for a ruling.
f)
An accessory to a medical device may
be classified separately using the classification
rules in this guidance document.
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g)
If,
based on the manufacturer?s intended
use, two or more classification rules
apply to
the device, the device is
allocated the highest level of classification
indicated.
h)
Where one medical device is intended to
be used together with a different medical
device, that may or may not be from the
same manufacturer, (e.g. a pulse oximeter and
a replaceable sensor sourced from a
different manufacturer, or a general purpose
syringe and a syringe driver), the
classification rules should apply separately to
each of
the devices.
i)
Classification
of an assemblage of medical devices that
individually comply with all
regulatory
requirements depends on the manufacturer?s purpose
in packaging and
marketing such a
combination of separate devices. For example:
?
If the
combination results in a product that is intended
by the manufacturer to
meet a purpose
different from that of the individual medical
devices that make it
up, the
combination is a new medical device in its own
right and should be
classified
according to the new intended use.
?
If the
combination is for the convenience of the user but
does not change the
intended uses of
the individual medical devices that make it up
(e.g. a
customised kit that provides
all the devices necessary to carry out a
particular
surgical procedure), the
classification allocated to the assemblage for the
purpose of a Declaration of Conformity
is at the level of the highest classified
device included within it.
j)
Classification
of an assemblage of medical devices where one or
more of the medical
devices that is in
the assemblage has yet to comply with all the
relevant regulatory
requirements,
should be for the combination as a whole according
to its intended use.
k)
While most software is incorporated
into the medical device itself, some is not.
Provided such standalone software falls
within the scope of the definition for a ?medical
device?, it is deemed to be an active
device and should be classified as
follows:
?
Where it drives or influences the use
of a separate medical device, it should be
classified according to the intended
use of the combination.
?
Where it is independent of any other
medical device, it is classified in its own
right using the rules in Section 7.0 of
this document.
l)
The historical experience of a RA may
require a particular type of medical device to be
allotted a different classification
from that assigned through the application of
these
classification rules.
6.2
Diagrammatic
Representation of the Classification System
CLASS
A
B
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LEVEL
Low Hazard
Low-moderate
DEVICE EXAMPLES
Bandages /
tongue depressors
Hypodermic Needles /
suction equipment
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Principles of Medical
Devices Classification
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Final Document GHTF/SG1/N77:2012
Hazard
C
D
Figure 1: Classification System for
Medical Devices
Note:
The
examples of medical devices provided in Figure 1
are for illustration
only and a
manufacturer of such a device should not rely on
it appearing as an
example but should
instead make an independent decision on
classification taking
account of its
particular design and intended use.
Moderate-high
Hazard
High Hazard
Lung ventilator
/ bone fixation plate
Heart valves /
implantable defibrillator
HIGHER
REGULATORY
REQUIREMENTS
LO
WER
A B C
D
DEVICE CLASS
Figure 2:
Conceptual illustration of regulatory controls
increasing with device class
Figure 2
indicates increasing regulatory controls as the
device class progresses from
Class A to
Class D. Such controls may require, for example:-
?
the
manufacturer to apply an independently audited
quality management system to
the design
and development process as well as to
manufacturing;
?
the RA or CAB to
review the
manufacturer?s
Summary Technical
Documentation,
including the clinical
evidence provided, to verify conformity to all
relevant
Essential Principles, prior to
the device being placed on the market;
?
the
manufacturer to undertake post-market evaluation
and testing of marketed
devices.
The concept is expanded in the GHTF
guidance document entitled
Principles
of
Conformity Assessment for Medical
Devices
.
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Medical Devices Classification
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6.3
Manufacturer’s
Determination
of Device Class
The manufacturer
should:
a)
Refer
to the GHTF guidance document entitled
Definition of the Terms
‘Medical
Device’
and ‘In
Vitro Diagnostic (IVD) Medical
Device’
to
confirm
the product
concerned is a medical device.
b)
Document the intended use of the
medical device.
c)
Take into consideration all the rules
that follow in order to establish the proper
classification for the device, noting
that
where a medical device has
features that
place it into more than
one class, classification, and conformity
assessment
should be based on the
highest class indicated.
d)
Determine if
the device is subject to special national rules
that apply within a
particular
jurisdiction and whether this affects the device
class.
e)
Ask the
RA to resolve any matter of interpretation, if
such exists.
7.0
Classification Rules
The
actual classification of each device depends on
the claims made by the
manufacturer for
its intended use and the technology/ies it
utilises. As an aid to interpreting
the purpose of each rule, illustrative
examples of medical devices that should conform to
the
rule have been provided in the
table below. However, it must be emphasised that
a
manufacturer of such a device should
not rely on it appearing as an example but should
instead
make an independent decision on
classification taking account of its particular
design and
intended use.
As
an aid to understanding how these rules may be
applied, a series of decision trees are
provided in Appendix A. These are for
illustrative purposes only and are
not
intended to be a
substitute for the
rules themselves
.
Manufacturers, RAs and CABs are advised
to refer to the definitions in Section 4.0 of
this document for a proper
understanding of the terms used within these
rules.
7.1
Non-
Invasive Devices
RULE
ILLUSTRATIVE EXAMPLES
Rule
1.
All non-invasive devices which
Devices covered by this rule are
extremely claim
sensitive.
come into contact with injured skin:
- are in Class A if they are intended
to
Examples: bandages; cotton wool.
be used as a mechanical barrier, for
compression or for absorption of
exudates only, i.e. they heal by
primary
intent;
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RULE
-
are in
Class B if they are intended to
be used
principally with wounds which
have
breached the dermis, including
devices
principally intended to manage
the
microenvironment of a wound.
unless
they are intended to
be used
principally with wounds which
have
breached the dermis and can only
heal
by secondary intent, in which case
they
are in Class C.
ILLUSTRATIVE EXAMPLES
Example: non-medicated impregnated
gauze
dressings.
Devices
used to treat wounds where the
subcutaneous tissue is as least
partially exposed
and the edges of the
wound are not sufficiently
close to be
pulled together. To close the wound,
new tissue must be formed within the
wound
prior to external closure. The
device
manufacturer claims that they
promote healing
through physical
methods other than ?primary
intent?
.
Examples: dressings for chronic
ulcerated
wounds; dressings for severe
burns.
Rule 2(i).
All non-
invasive devices
intended for
channelling or storing
?
liquids, or
?
gases
for the purpose of
eventual infusion,
administration or
introduction into the
body are in Class
A,
unless
they may be
connected to an
active medical device
in Class B or a
higher class, in which
case they are
Class B;
Such devices are
?indirectly invasive? in that
they
channel or store liquids that will eventually
be delivered into the body.
Examples: administration sets for
gravity
infusion; syringes without
needles.
Examples: syringes and
administration sets for
infusion pumps;
anaesthesia breathing circuits.
NOTE:
“Connection” to an active device covers
those circumstances where the safety
and
performance of the active device is
influenced by
the non-active device and
vice versa
.
Rule
2(ii).
All non-invasive devices
Examples: tubes used for blood
transfusion,
intended to be used for
organ storage containers.
?
channeling
blood, or
?
storing or
channeling other body
liquids, or
?
storing organs, parts of organs or
body tissues,
for the purpose of eventual infusion,
administration or introduction into the
body are Class B.
unless
they are blood bags,
in which
case they are Class
C.
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Example:
Blood
bags that do not incorporate an
anti-
coagulant.
Page 13 of 30
Principles of Medical
Devices Classification
Study Group 1
Final Document GHTF/SG1/N77:2012
RULE
ILLUSTRATIVE EXAMPLES
NOTE:
In some jurisdictions,
blood bags have a
special rule that
places them within a different
class.
Rule 3.
All non-invasive
devices
intended for modifying the
biological or
chemical composition of
?
blood,
?
other body
liquids, or
?
other liquids,
intended for infusion into the body are
in Class C,
Such
devices are
?
indirectly
invasive
?
in that
they treat or modify substances that
will
eventually be delivered into the
body. They are
normally used in
conjunction with an active
device
within the scope of either Rule 9 or 11.
Examples: haemodializers; devices to
remove
white blood cells from whole
blood.
NOTE
: For the
purpose of this part of the rule,
?modification? does not include simple,
mechanical filtration or centrifuging
which are
covered below.
Examples: devices to remove carbon
dioxide;
particulate filters in an
extracorporial circulation
system.
These devices either do not touch the
patient or
contact intact skin only.
Examples: urine collection bottles;
compression
hosiery; non-invasive
electrodes, hospital beds.
7.2
Invasive
Devices
RULE
Rule
5
. All invasive devices with
respect to body orifices (other than
those which are surgically invasive)
and
which:
?
are not intended for connection to an
active medical device, or
?
are intended
for connection to a
Class A medical
device only.
- are in Class A if they
are intended for
transient use;
- are in Class B if they are intended
for
short-term use;
unless
they are intended for
short-term
November
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unless
the treatment
consists of
filtration, centrifuging or
exchanges of
gas or of heat, in which
case they are in
Class B.
Rule 4.
All other non-
invasive devices
are in Class A.
ILLUSTRATIVE EXAMPLES
Such
devices are invasive in body orifices and
are not surgically invasive (refer to
definition in
Section 4). Devices tend
to be diagnostic and
therapeutic
instruments used in ENT,
ophthalmology,
dentistry, proctology, urology
and
gynaecology. Classification depends on the
duration of use and the sensitivity (or
vulnerability) of the orifice to such
invasion.
Examples: examination
gloves; enema devices.
Examples:
urinary catheters, tracheal tubes.
Examples: dressings for nose bleeds.
Page 14 of 30
Principles of Medical Devices
Classification
Study Group 1 Final
Document GHTF/SG1/N77:2012
RULE
use in the oral cavity
as far as the
pharynx, in an ear canal
up to the ear
drum or in a nasal
cavity, in which case
they are in Class
A,
- are in Class C if they are
intended for
long-term use;
Example: urethral stent; contact lenses
for long-
term continuous use (for this
device, removal of
the lens for
cleaning is considered as part of the
continuous use).
Examples:
orthodontic materials, removable
dental
prosthesis.
ILLUSTRATIVE EXAMPLES
unless
they are intended for
long-term
use in the oral cavity as far
as the
pharynx, in an ear canal up to
the ear-
drum or in a nasal cavity and
are not
liable to be absorbed by the
mucous
membrane, in which case they are
in
Class B.
All invasive
devices with respect to
body orifices
(other than those which
are surgically
invasive) that are
intended to be
connected to an active
medical device
in Class B or a higher
class, are in
Class B.
Rule 6
. All
surgically invasive devices
intended
for
transient use
are in
Class
B,
unless
they are reusable
surgical
instruments, in which case
they are in
Class A; or
unless
intended
to supply energy in the
form of
ionizing radiation, in which
case they
are in Class C; or
unless
intended to have a biological
effect or
be wholly or mainly absorbed,
in which
case they are in Class C; or
Examples:
tracheal tubes connected to a
ventilator; suction catheters for
stomach
drainage; dental aspirator
tips.
NOTE:
Independent of
the time for which they
are invasive.
A majority of such devices fall into
several
major groups: those that create
a conduit through
the skin (e.g.
syringe needles; lancets), surgical
instruments (e.g. single-use scalpels;
surgical
staplers; single-use aortic
punch); surgical
gloves; and various
types of catheter/sucker etc.
Examples:
Manually operated surgical drill bits
and saws.
NOTE
: A surgical instrument
connected to an
active device is in a
higher class than A.
Example: catheter
containing sealed
radioisotopes.
NOTES
: (a) T
he
?biological effect? referred to
is an
intended one rather than unintentional. The
term ?absorption? refers to the
degradation of a
material
within the body and the metabolic
elimination of the resulting
degradation products
from the body.
(b) This part of the rule does not
apply to those
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Page
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