Note: Descriptions are shown in the official language in which they were submitted.
CA 02593674 2007-07-11
MEDICAL GAS DELIVERY METHOD AND APPARATUS
TECHNICAL FIELD
Embodiments of inventions described herein relate to the supply of medical
gases in the
environment of a medical facility. More specifically, one or more embodiments
are concerned
with connecting a secondary gas supply to a medical gas supply system in a
safe and efficient
manner in the event that the primary supply is unable or unsuitable to deliver
gas as required.
Furthermore one or more embodiments: provide a source and method to access
medical gases in
the event of an emergency; expand an existing system to support additional
patient needs in the
event of a catastrophic event; and provide a safer more efficient means for
testing medical gas
alarms monitoring the medical gas piping system.
BACKGROUND ART
It is often necessary for trained personnel to provide a variety of gases of
medical quality
in a medical facility. Examples of such gases include medical air, oxygen,
nitrogen, nitrous
oxide, and carbon dioxide. Systems are also often installed in medical
facilities which provide
vacuum or gas evacuation. Gas service may be provided through a system which
delivers the
gas throughout a facility or portions or zones thereof. A number of primary
supply sources of
gas are used to deliver gas through outlet ports positioned at locations
within the medical facility.
The delivery system for each type of gas commonly includes manifolds with
appropriate shut-off
valves and pressure gauges. The delivery system also commonly includes at
least one pressure
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regulator, check valve, and piping supply lines connecting the elements of the
system. The
primary supply source for each gas may be located in a secure area in the
interior of the medical
facility. Alternatively a primary supply source may be located at the exterior
of the facility for
maintenance by outside vendors providing the various gases.
It is critically important that the correct gas at the proper pressure be
supplied when
required from a medical gas supply system. Great effort is taken to assure
that the various gases
supplied are clearly marked at all locations. The possibility for delivery of
the wrong gas at an
incorrect location must be minimized. The pressure of each gas delivered may
also be
appropriately monitored throughout the system.
There are occasions which may require a secondary gas source to be connected
to the gas
delivery system of a medical facility. These instances might involve an
emergency, a need for
maintenance, a requirement of inspection, certification testing or service.
One method of
connecting the secondary gas source involves connecting the secondary gas
source to the system
through a hose to a conduit in the facility which normally serves as an
outlet. Such an
arrangement, known as backfeeding in the industry, is undesirable according to
the National Fire
Protection Association (NFPA), the regulatory agency responsible for medical
gas piping
standards. Such a connection, according to NFPA, should not be done.
Gases delivered by medical gas systems are generally at relatively low
pressures. Typical
desired pressure levels are 50 psi for oxygen, nitrous oxide, carbon dioxide
and medical air, 180
psi for nitrogen, and 15 in/Hg to 25in/Hg for vacuum or gas evacuation.
Bottled gases by
comparison have considerably higher pressures, commonly about 2000 psi. If the
wrong gas
were delivered to the wrong supply line through backfeeding, incorrect
pressure or flows in
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portions of the system may occur. Such incorrect pressures and flows may place
equipment and
personnel at risk.
The medical system for each gas type is designed to provide gas flow from the
primary
source toward the various outlets and devices which utilize the gas within the
medical facility.
Gas should not be allowed to flow in a direction opposite to that for which
the equipment was
designed. Reverse operation requires a user to thoroughly understand every
component of the
system and what is necessary to safely accomplish reverse flow. It is often
difficult to conduct
such an analysis when many types of devices may be connected to the system.
For these reasons NFPA has disapproved of the practice of backfeeding of gas
supply
lines. Despite the NFPA position, personnel in medical facilities when faced
with the necessity
of keeping gas systems in operation are forced to use such backfeeding
connections. In 1996
NFPA took the position that emergency service of an oxygen supply could be
provided by a low
pressure inlet located in the main supply line. This inlet is required to be
located at the exterior
of the medical facility. The use of such an inlet is authorized only for use
to achieve an
emergency supply of oxygen and is not to be used in the case of
inspection/certification. Since
this emergency inlet port is not required to be retrofit into existing
"grandfathered" systems,
most medical facilities are not equipped with this capability. Such an
arrangement is of no help
when the problem in the system is something other than the main supply, such
as a system break
inside the medical facility. In addition, gas delivery systems are normally
divided into zones.
This port does not allow gas service to be selectively supported or
inspection/certification
activities to be performed by selected zones. As a result, even in oxygen
systems which have
such a port the practice of backfeeding is sometimes necessary.
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Thus there exists a need for an apparatus and method for connecting a
secondary supply
of a medical gas to a medical gas supply system. There further exists a need
for an apparatus and
method of connecting such a secondary supply of medical gas in a quick and
reliable manner,
which can be connected to selected zones of the supply system and which does
not require
backfeeding of any portion of the gas supply system.
DISCLOSURE OF INVENTION
An exemplary embodiment may include a method of connecting a secondary gas
source
to a medical gas supply system in a medical facility. Gas piping carries each
gas from a primary
supply source, through supply lines and to various outlets and devices in the
medical facility or
portions thereof. A valve box referred to herein as a control panel is
positioned in a main supply
line. The main supply line may supply the entire system or a portion or zone
within the system.
The control panel houses a shut off valve which when closed separates the
primary supply source
from the balance of the system. Also housed within the control panel is an
inlet port for
connection to a secondary gas supply. The inlet port is fluidly connected to
the system
downstream and/or upstream of the valve. Access to the valve and the inlet
port in the control
panel is normally prevented by a removable face on the control panel. The
control panel is
constructed so that if the removable face is in position on the control panel
it is required that the
valve is in an open condition so that the system is being supplied from the
primary gas supply
source.
In situations when it is necessary to supply the system or a respective zone
controlled
from the control panel from a secondary gas supply source, the face of the
control panel is
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removed. The valve in the interior of the control panel is closed. This
isolates the primary
supply source and other system components upstream of the control panel from
the system and
devices downstream of the control panel. The secondary gas supply source is
connected to the
inlet housed in the control panel. Gas from the secondary source is allowed
into the system in a
controlled fashion through the inlet to maintain the gas supply to downstream
components. This
inlet port must be provided with a gas specific connection such as a threaded
coupler using a
diameter indexed safety system (DISS) or any style of quick connect fittings
common to the
industry. Only a mating gas specific connection can be connected to the port.
Mounting of the
mating specific threaded coupler to the port is operative to open a demand
check valve to place
the secondary gas supply in fluid communication with the system. This
arrangement increases
the probability that only a secondary gas source suitable to use in the system
can be connected to
a specific inlet port.
An exemplary embodiment includes a method of upgrading an existing control
panel of a
medical gas delivery system to include a gas specific DISS threaded coupler.
Such existing
control panels typically comprise an enclosure and a cover (e.g. door, window,
removable panel)
operative to close an opening to the enclosure. The enclosure includes therein
a least one valve
and first and second pipelines in operative connection with each respective
end of the at least one
valve. The first and second pipelines each include a front facing side which
faces the opening to
the enclosure. The front facing side of the first pipeline may include a
threaded opening therein.
A pressure gauge is typically mounted in the threaded opening and is typically
viewable through
a transparent portion of the cover to the enclose.
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In this described embodiment, the method of upgrading the control panel may
include
removing the pressure gauge from the threaded opening of the first pipeline.
This described
method then includes mounting a fitting to the threaded opening of the first
pipeline. The fitting
includes a body and a threaded projection extending from the body. The
threaded projection is
installed into the threaded opening of the first pipeline. The body also
includes at least two ports
therein which are in fluid communication with an opening through the threaded
projection. A
first one of the ports includes a gas specific DISS threaded coupler mounted
thereto, which
extends from the fitting in a direction that is substantially perpendicular to
a longitudinal axis of
the projection of the fitting. A second one of the ports may include a second
pressure gauge
which extends from the fitting in a direction that is substantially
perpendicular to the longitudinal
axis of the projection of the fitting. After being mounted to the threaded
opening of the first
pipeline, the fitting is of a size and configuration which ensures that the
gas specific DISS
threaded coupler, and the second pressure gauge do not extend through the
opening of the
enclosure.
In this described embodiment, the method may include connecting a secondary
gas
source to the gas specific DISS threaded coupler. The secondary gas source may
include a
pressure vessel with a valve, a regulator, and a mating specific threaded
coupler adapted to
mount to the gas specific DISS threaded coupler and place the secondary gas
source in fluid
communication with the first pipeline. The method may further includes opening
the valve on
the pressure vessel so as to deliver gas from the pressure vessel into the
first pipeline. The
method may also include closing the valve of the medical gas delivery system
and controlling the
pressure of gas applied from the pressure vessel into the medical gas system
through use of the
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regulator associated with the pressure vessel. Examples of control panels that
have been adapted
to include gas specific DISS couplers is found in the inventor's U.S. Patent
No. 6,305,400 BI.
In an alternative embodiment, once the fitting has been mounted to an existing
control
panel, as described previously, the gas specific DISS threaded coupler my be
used to mount an
additional medical gas outlet port to the control panel. For example, a
further exemplary
embodiment may include connecting a secondary gas outlet to the gas specific
DISS threaded
coupler. The secondary gas outlet may include at least one outlet port and a
mating specific
threaded coupler adapted to mount to the gas specific DISS threaded coupler
and place the
secondary gas outlet in fluid communication with the first pipeline. The
method may further
include connecting a gas delivery mask to the at least one outlet port and
providing a medical gas
to a patient through the gas delivery mask. In this described alternative
exemplary embodiment,
the secondary gas outlet may include a plurality of outlet ports, wherein each
outlet port is
mounted to a wall of a hallway to form a medical gas rail. In an emergency in
which large
numbers of patients require medical gases, the method may include connecting a
plurality of the
gas delivery masks to the plurality of outlet ports. Patients located in
hallways of the hospital or
in waiting rooms may then be provided with medical gas through the delivery
masks connected
to the medical gas rail.
In addition, the described system is capable of being quickly adapted in an
emergency or
non-emergency setting to provide medical gases for all medical and clinical
needs. For example,
the described system could be quickly adapted to provide medical gases in the
operating room
area for emergency surgeries.
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It should also be understood that exemplary embodiments may further include
using the
above described fitting in new equipment such as new control panels for medial
gas delivery
systems. As discussed previously the fitting may comprise a body including an
internal cavity
through which medical gases are capable of flowing. The body of the fitting
may also include a
threaded projection extending from the body. This threaded projection includes
an opening
therein to the cavity in the body. In addition, this threaded projection may
be adapted to connect
to one of one or more threaded openings of in a medical gas pipeline in the
control panel.
The body of the fitting may also include at least two ports. Each of the ports
includes an
opening therein to the cavity in the body. A first one of the ports is adapted
to receive a gas
specific DISS threaded coupler mounted thereto, which extends from the fitting
in a direction
that is substantially perpendicular to a longitudinal axis of the projection
of the fitting. A second
one of the ports is adapted to receive a pressure gauge mounted thereto which
extends from the
fitting in a direction that is substantially perpendicular to the longitudinal
axis of the projection
of the fitting. In this described exemplary embodiment, the fitting has a
size, such that when the
fitting is mounted to the threaded opening of the medical gas pipeline, the
fitting places the gas
specific DISS threaded coupler and the pressure gauge in positions which do
not extend the
DISS threaded coupler and the pressure gauge through an opening of an
enclosure of the control
panel.
In exemplary embodiments of a control panel that includes the above described
fitting,
the control panel may be produced with the gas specific DISS threaded coupler
in operative
connection with the first one of the ports of the fitting. Also the control
panel may be produced
with the pressure gauge in operative connection with the second one of the
ports of the fitting. As
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discussed previously, such a control panel may be comprised of the enclosure
and the cover
operative to close the opening to the enclosure. Such a control panel also
includes a least one
valve and first and second pipelines in operative connection with each
respective end of the at
least one valve. The first and second pipelines each include a front facing
side which faces the
opening to the enclosure. The front facing side of one or both of the
pipelines may include a
threaded opening therein. The threaded projections of one or more of the
described fittings may
be in operative connection with the threaded opening(s) in one or both of the
pipelines for one or
more valves of the control panel. As discussed previously, when the control
panel is configured
in this manner, the DISS threaded coupler(s) and the pressure gauge(s) mounted
to each fitting in
the control panel will not extend through the opening of the enclosure of the
control panel. Also
in exemplary embodiments, additional DISS threaded couplers may be mounted to
the described
fittings in the control panel. Also one or more transducers may be mounted in
the control panel
which are connected via a hose or other conduit to the DISS threaded
coupler(s) of the described
fitting(s).
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a plan view of a control panel for zone shut-off valves in a
medical gas supply
system.
Figure 2 is an exemplary schematic diagram representative of a medical gas
supply
system.
Figure 3 is an exemplary schematic diagram representative of a manifold
portion of the
medical gas supply system including an inlet port.
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Figure 4 is an exemplary schematic diagram representative of the manifold
portion of the
medical gas supply system including a secondary gas supply connected to the
inlet port.
Figures 5 and 6 are exemplary schematic diagrams representative of connecting
a
transducer to the secondary gas inlet port of the medical gas supply system.
Figure 7 is an exemplary schematic diagram representative of a transducer port
retrofit
assembly.
Figure 8 shows a top plan cross-sectional view of an existing control panel
mounted into
a wall.
Figure 9 shows a side plan view of the control panel mounted to the wall in
which a
pressure gauge has been removed.
Figure 10 shows an exemplary embodiment of a fitting adapted to mount in-place
of the
removed pressure gauge.
Figure 11 shows a top plan cross-sectional view of the control panel with the
new fitting
threaded into a threaded opening previously used for mounting the removed
pressure gauge.
Figure 12 shows a schematic view of the described fitting and components which
may be
mounted thereto.
Figure 13 shows a perspective view of the fitting mounted in the control
panel.
Figure 14 shows a perspective view of two fittings mounted in the control
panel on either
side of a valve.
Figure 15 shows a perspective view of a control panel that includes a
transducer mounted
via a hose to the fitting.
CA 02593674 2007-07-11
Figure 16 shows an example of medical gas rails mounted to a hallway wall,
which rails
are in operative connection with the described fittings mounted in the control
panel.
BEST MODES FOR CARRYING OUT INVENTION
Referring now to the drawings and particularly to Figure 1 there is shown
therein a valve
box 10 which is referred to herein as a control panel 10. Control panel 10 is
designed to be
installed in a medical gas supply system in a medical facility which employs
an exemplary
embodiment. The panel 10 includes a face 11. Panel 10 shown in this example is
designed to
accommodate controls and fluid connections for three separate gases. Each
control panel
installation in a gas supply system may need to accommodate more or less than
three gases. The
control panel may be specifically designed for the number of gases required to
flow
therethrough. In the exemplary embodiment face 11 has gas identification
placards 12, 13 and
14 for each gas which passes therethrough. The gas identification placards 12,
13 and 14 may
include specific markings and indicia which indicate the particular medical
gas which flows in
each line and the area of the facility served by each valve.
In the exemplary embodiment of control panel 10 faces of pressure gauges 18,
19 and 20,
one for each gas, are visible through the face 11. Pressure gauges 18, 19 and
20 monitor
pressure at the control panel location in the system. Gas types commonly
provided through the
use of panel 10 in a medical facility include (but are not limited to) medical
air, oxygen,
nitrogen, nitrous oxide, carbon dioxide and vacuum or gas evacuation. In the
case of oxygen,
nitrous oxide, carbon dioxide and medical air, the pressure gauge face
commonly reads in a
range from 0 to 100 psi. For nitrogen the gauge face commonly reads in a range
from 0 to 300
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psi. For vacuum or gas evacuation the gauge face reads in a range from 0 to 30
in/Hg. It should
be understood that while in the exemplary embodiment gauges are used as
pressure indicators, in
other embodiments other types of pressure indicating devices may be used. The
frame of the
face 11 of the panel is attached by screws which releasably secures the frame
of the face to the
control panel 10. In the exemplary embodiment the face may be removed from the
panel by
pulling on a ring 22. The face of the control panel is reinstalled by moving
the panel into
position. In embodiments various releasable latching mechanisms may be used to
secure the
face to the control panel.
Figure 2 illustrates the control panel 10 installed in a simplified exemplary
embodiment
of a medical gas delivery system. Face 11 of the panel has been removed to
reveal the contents
thereof. Pressure gauges 18, 19 and 20 are located within the enclosure of
panel 10.
Additionally, shut-off valves 24, 25 and 26, one for each of the gas lines,
are housed within the
panel. The pressure gauges are positioned in the panel on the downstream side
of the valves.
The shut-off valves 24, 25 and 26 in the exemplary embodiment may be three-
piece in-
line repairable ball type valves. In the exemplary embodiment they are
constructed of bronze
and have Teflon seats and seals. The valves are commonly rated at 600 psi.
Each valve
includes adjustable packing and a blowout proof stem. Valves 24, 25 and 26 are
operated by
lever handles 28, 29 and 30. Operation of the valve from fully open to fully
closed requires only
one quarter of a full turn of the handle. The control panel maybe constructed
so that the handle
extends outward when in the closed position. As a result the face must be
removed from the
panel when a valve is in a closed position. This is useful in enabling quick
visual inspection of
the conditions of the valves.
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A control panel 10 may be used as part of a gas feed system zone manifold in a
plurality
of zones required throughout the medical facility. The facility is sectioned
into zones requiring
similar gases or uses with a valve controlling the supply of gas to each zone.
Control panels may
also be positioned for specific sub-zones or areas within the facility. The
zone arrangement
simplifies inspection and maintenance in that only a specific zone could be
incapacitated or
require gas delivery from a secondary source. By pulling the ring 22 and
removing face 11 of
the control panel, one or more shut-off valves 24, 25 or 26 within the panel
are enabled to be
closed. By closing the appropriate valve a particular zone or line in the
system could be isolated
without interfering with the balance of the gas delivery system.
The exemplary control panel 10 includes primary source inlets 32, 33 and 34
upstream of
the shut-off valves 24, 25 and 26. Pressure regulators 40, 41 and 42, one for
each gas supply
line, are connected upstream of the respective check-valve 36, 37 and 38. The
pressure
regulators are adjusted to supply the particular gas within the desired
pressure ranges as noted
above.
A primary gas source 44, 45 and 46, is connected upstream of the respective
pressure
regulator 40, 41 and 42. One primary gas source is provided for each of the
gases the system is
to deliver. In an exemplary embodiment each primary gas source 44, 45 and 46
may include a
pressure vessel accessible from the exterior of the facility. The primary gas
sources are therefore
readily available to agents of an outside vendor for the purpose of servicing
and refilling. In
alternative embodiments other primary sources such as compressors, oxygen
concentrators or
other devices which produce or deliver the medical gas may be used. In systems
which supply
vacuum, an appropriate vacuum pump or similar device is connected to a
respective line.
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The control panel 10 has outlets 48, 49 and 50 located downstream of the
pressure gauges
18, 19 and 20. These outlets connect the control panel to the balance of the
gas delivery system
within the zone or other area controlled by the control panel. Outlet ports
54, 55 and 56 are
shown connected to outlets 48, 49 and 50, respectively. These outlets are
representative of a
plurality of outlets that may be connected to the gas system in the zone
controlled by panel 10.
All of the individual elements of the gas delivery system are interconnected
with appropriate
piping. In the exemplary embodiment each outlet port 54, 55 and 56 includes a
gas specific
diameter indexed safety system (DISS) threaded coupler 58, 59 and 60. In such
a system only a
unique fitting size and/or coupling type is used in connection with each
medical gas. These gas
specific sizes and/or coupling types provide increased assurance that only the
correctly mating
gas apparatus is connected to the line.
In the exemplary system shown a mating threaded closure or cap 62, 63 and 64
is located
closely adjacent to the respective coupler. The caps may be attached to an
area adjacent each
outlet port 54, 55 and 56 through the use of a chain or wire. This reduces the
risk that a removed
cap will be lost. Although shown unthreaded for purposes of clarity of
description, caps 62, 63
and 64 must be engaged on threaded outlet ports 58, 59 and 60 whenever an
apparatus is not
engaged to the outlet. This arrangement minimizes the risk that foreign matter
enters an outlet
port 54, 55 and 56 to cause contamination of the system. However, it is to be
understood that not
all styles of outlets are threaded and therefore not all outlets require caps.
During normal conditions each required medical gas type is available at each
primary gas
source 44, 45 and 46 and the shut-off valves 24, 25 and 26 in the control
panel are open.
Medical personnel can access a particular gas line as needed. This is
accomplished by attaching
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a desired apparatus to an outlet port 58, 59 or 60. Gas flows in the desired
direction only from
the source to the outlets at the proper pressure for the gas utilizing devices
connected to the
system.
In the event of a system failure in which any element of the system upstream
of shut-off
valve 24, 25 or 26 fails or requires service, face 1 I of the control panel 10
is removed by pulling
on the ring 22. The appropriate shut-off valve 24, 25 or 26 for the gas type
involving the failure
may then be closed. This would be the case if a primary gas source 44, 45 or
46 became empty
or another system component upstream of the control panel malfunctioned. The
appropriate
shut-off valve 24, 25 or 26 is closed so the system is not contaminated and
there is no flow
backward toward the primary supply source. Closing the valve in the control
panel also isolates
the zone downstream of the control panel from the remainder of the system.
In an exemplary embodiment, shown in Figure 3, an inlet port 70 is connected
in a gas
conduit adjacent pressure gauge 20 within the control panel. The inlet port 70
may have a gas
specific DISS threaded coupler 74 incorporating a demand check valve 71. A
mating gas
specific threaded closure or cap 78 serves to secure the inlet port when not
in use to minimize the
risk of contamination and provide additional protection from possible gas
leakage. The cap 78
may he secured to inlet port 70 by a chain or wire when not in use. A demand
check
incorporated into the gas specific DISS threaded coupler 74 is connected to
inlet port 70 for the
purpose of assuring that pressurized gas may only flow in a direction into the
inlet port 70 and
serve as a primary seal when the system is in normal use. When shut-off valve
26 is closed, inlet
port 74 may be used to supply the zone downstream of the control panel with
gas from a
secondary supply source.
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Figure 4 shows a secondary source of gas, including a pressure vessel 82,
connected to
the inlet port 70 in the control panel 10. The secondary gas source includes a
valve 84 and
regulator 86 which control the pressure at which gas is delivered. The
pressure vessel 82 is
connected to deliver gas to inlet port 70 through a mating gas specific DISS
threaded coupler 88.
Coupler 88 in the embodiment shown is at the end of a hose 90 leading from
regulator 86 of the
secondary gas source. Once the proper connection of pressure vessel 82 to
inlet port 70 has been
made, valve 84 is opened to establish the fluid connection with the secondary
source. Gauge 20
on the control panel provides an indication that the secondary source is
supplying gas at the
appropriate pressure. The secondary source supplies gas on an interim basis
through the inlet
port without backfeeding any portion of the system upstream of the valve 26
when in the closed
position. As a result gas flows in the normal manner to all devices connected
in the system
downstream of the shut off valve. Valves 24 and 25 may be configured in a
similar fashion.
In the exemplary embodiment inlet ports 68, 69 and 70 are connected to
respective gas
conduits in the control panel adjacent pressure gauges 18, 19 and 20. Each
inlet port 68, 69 and
70 includes a gas specific DISS threaded coupler 72, 73 and 74 to minimize the
risk of an
incorrect connection. Mating caps 76, 77 and 78, respectively, correspond to
the gas specific
threaded coupler 72, 73 and 74 on the inlet ports to close the inlet ports
when not in use. The
control panel enables connecting a secondary source of gas for each gas type
used in the system.
Multiple gas sources and gas types may be connected through a single control
panel.
The explanation herein has centered around maintaining gas supply despite a
depleted or
inoperative primary source of gas. In the event that maintenance, inspection
or certification of a
portion of the gas delivery system is required, a secondary gas source could
be connected.
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Secondary gas sources may be used to supply selected zones which are isolated
by the shut off
valves from other zones. The demand check associated with the inlet for the
secondary gas
source assures that the primary and secondary sources may be connected and
disconnected
through the control panel in a manner that provides an uninterrupted supply of
gas to the zone
and which avoids loss of gas or damage to the system.
When gas flow from the primary source is to be restored, the shut-off valve
connecting
the gas source in the control panel may again be opened. The valve from the
secondary source is
then closed and the connection to the secondary inlet in the control panel
disconnected. A
demand valve in item 74, 58, 59 or 60 automatically closes preventing any
escape of gas. The
cap on the inlet is then installed. The face may then be attached to the
control panel to indicate
that all the valves within the panel are open.
The exemplary embodiment may also be used to facilitate the introduction of
purging
gases into a portion of the medical gas system. When additions or maintenance
to medical gas
systems are performed, NFPA 99 requires that purging gases such as nitrogen be
placed into the
medical gas pipeline prior to brazing. The purging gas reduces the formation
of copper oxide
during the brazing process by removing oxygen and moisture from the pipeline.
In the
exemplary embodiment the secondary input ports 68, 69, 70 provide readily
available ports
through which a purge gas may be input into the system.
In addition to providing a gas specific secondary inlet for medical and purge
gases, the
exemplary embodiment of the control panel 10 may also be used for the remote
connection of
monitoring transducers. Figure 5 shows a transducer assembly 98 being placed
in connection
with the inlet port 102. Here the transducer assembly includes at least one
transducer 100 which
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is operative to remotely monitor properties of gases in the system. In the
exemplary embodiment
the transducer assembly further includes a demand check valve 104 which is
operative to prevent
outside gases and other contaminants from entering the system when the
transducer is installed,
repaired or replaced.
Figure 6 is representative of an alternative transducer assembly 110, which
includes a
second connection end 112. The second connection end 112 enables the
connection of addition
transducers to the manifold. In addition the second connection end 112 can be
configured to
accept a secondary gas source by including a demand check valve and a DISS
threaded coupler
as previous described.
Embodiments may also encompass retrofitting existing medical gas supplies to
include
one or more transducers. As shown in Figure 7 a retrofit transducer assembly
126 may be
adapted for placement between a preexisting gauge 124 and a gas conduit 122.
In this described
embodiment the preexisting gauge 124 may be removed from a gauge port 128 of
the conduit
122 and the transducer assembly 126 may be threaded in its place. The
transducer assembly
includes a tee connector 120 that is adapted to be threaded into the gauge
port 128 and is adapted
to accept the connection of the original gauge 124. As previously described
the exemplary
transducer assembly 126 further includes a demand check valve 130 and at least
one transducer
132.
Configuring the exemplary control panel 10 to include remote transducers:
enables
transducers to be more easily found, replaced, and maintained; and facilitates
the required annual
testing of the medical gas alarm systems. Also the labeling of the exemplary
embodiment of the
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CA 02593674 2011-03-25
control panel further facilities the identification of those areas, rooms,
and/or zones which are
being monitored by each transducer.
Control panels for zone shut-off valves in a medical gas supply system are
often located
in hallways of a hospital, and therefore are typically designed to have a
relatively thin profile, so
as to minimize the amount of distances the control panel extends from a
hallway wall. As a
result there is often very little room between a front cover (e.g. front door
or window) of the
control panel and components mounted inside the control panel such as valves
and pressure
gauges. Figure 8 shows a top plan cross-sectional view of an existing control
panel 300 mounted
into a wall 302. This described control panel includes an enclosure 311 and a
cover 314
operative to close an opening to the enclosure such as a door and/or window.
Inside the
enclosure the control panel includes two gas pipelines 304, 306 separated by
at least one valve
308. At least one of the pipelines 304 includes a threaded opening 301 adapted
to receive a
pressure gauge 310. In this described embodiment, the threaded opening is
positioned on a front
facing side of the pipeline facing the cover 314 of the enclosure. The
threaded opening is
positioned on the front facing side of the pipeline to enable the pressure
gauge 310 threaded
therein to extend from the pipeline in a horizontal direction 312 towards the
cover 314 of the
control panel.
Figure 9 shows a side plan view of the control panel 300 in which the pressure
gauge has
been removed from the threaded opening 301. To enable such an existing control
panel 300 to
be upgraded to include the above described gas specific DISS threaded
couplers, an exemplary
embodiment may include employing a new adapter fitting which is operative to
mount in the
existing threaded opening 301 previously used for a pressure gauge, but which
fitting does not
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CA 02593674 2007-07-11
block the cover (e.g. door and/or window) of the control panel from being
closed. Figure 10
shows an example of such a fitting 200. The fitting includes a body 204 with
an internal cavity
therein through which medical gases are capable of flowing. The fitting
further includes a
threaded projection 202 extending from the body, which projection is adapted
to be threaded into
the existing threaded opening 301 in an existing control panel 300. The
threaded projection
includes an opening 209 to the internal cavity of the body.
In this described embodiment, the fitting is adapted to have a length 206
between the end
of the projection 208 and the opposed end 210 of the body which enables all of
the fitting to be
located within the control panel such that the cover of the control panel may
be closed when the
fitting is mounted to a threaded opening 301 in the control panel.
Figure 11 shows a top plan cross-sectional view of the control panel with the
new fitting
200 threaded into the threaded opening 301 (Figure 9) previously used for a
pressure gauge.
When mounted in this manner, the fitting extends from the pipeline 304 a
distance 320 which is
less than the distance 322 between the pipeline 304 and an inside surface of
the cover 314 of the
control panel.
Referring back to Figure 10, the body 204 of the fitting 200 includes at least
one port 212
which extends into the body to the internal cavity of the body. The at least
one port 212 is
orientated such that a longitudinal axis 214 of the port extends in a
direction that is substantially
perpendicular to the longitudinal axis 216 (Figure 12) of the projection 202
and/or extends in a
direction that is substantially parallel to the inner surface of the cover of
the control panel when
mounted to the threaded opening 301 in the side of the pipeline in the control
panel.
CA 02593674 2007-07-11
Figure 12 shows a schematic view of the described fitting 200 and components
which
may be mounted thereto. In this described embodiment, the body of the fitting
200 includes
three ports 212, 220, 222 which are adapted to mount components so as to
orientate respective
longitudinal axes 214, 226, 224 of the components in directions which extend
substantially radial
with respect to the longitudinal axis 216 of the threaded protection 202
and/or which extend
substantially parallel to the inner surface of the cover of the control panel
when mounted to the
threaded opening 301 (Figure 9) in the control panel.
As shown in Figure 12, various components may be mounted to the ports 212,
220, 222
of the fitting 200. Such components may include a pressure gauge 230, a gas
specific DISS
threaded coupler 232, transducers and other medical gas related fittings
and/or components. In
addition an elbow coupler 234 or other coupler may be mounted to a port of the
fitting 200 to
enable other components to extend from the fitting in directions that are not
radial with respect to
the longitudinal axis 216 of threaded projection 202. For example as shown in
Figure 12, a
second gas specific DISS threaded coupler 236 may be mounted to the elbow
coupler 234 so that
it extends parallel to the first gas specific DISS threaded coupler 232 and
parallel to the inner
surface of the cover of the control panel when mounted to the threaded opening
301 (Figure 9) in
the control panel.
Figure 13 shows a perspective view of the fitting 200 mounted in the control
panel 300.
Figure 14 shows a perspective view of the control panel in which fittings 200,
400 have been
mounted to both sides of the valve 308. As shown in Figures 13 and 14 the
fitting(s) enable gas
specific DISS threaded couplers 232 and 402, pressure gauges 230, 406, and
other components
to be mounted to an existing control panel without interfering with the
operation of the valve 308
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CA 02593674 2007-07-11
or without interfering with closing the cover mounted to close the opening 404
to the control
panel.
As discussed previously the gas specific DISS threaded couplers mounted to the
described fitting may be used for backfeeding medical gases into the piping
system. When back
feeding is necessary, the medical gas piping system does not need to be taken
to atmosphere.
Also, providing a gas specific DISS threaded coupler on one or both sides of
the valve can
reduce costs for future tie ins or remodeling work involving the medical gas
piping system. For
example, providing a gas specific DISS threaded coupler on one or both sides
of the valve allows
areas of the medical gas piping system to remain in service (thru backfeeding)
while area(s) on
the upstream side of the valve are being demolished or renovated.
As shown in Figure 15, in an exemplary embodiment, one or more transducers 440
may
be mounted via a bracket 444 to an inside wall of the control panel or other
location. A hose 442
or any other industry approved conduit may be placed in operative connection
between the
transducer 440 and a second DISS threaded coupler 236 connected to the fitting
using the
previously described elbow coupler 234. Such a transducer may be capable of
monitoring
characteristics of the medical gas such as pressure. Transducers connected to
the medical gas
system via the described fittings may be used in conjunction with a medical
gas alarm to monitor
and trigger an appropriate alarm when the pressure conditions of the medical
gas pipeline are
outside normal parameters. Mounting transducers in the control panel enables
locating, required
annual testing and servicing of the transducers to be performed faster and
easier than traditional
installation of transducers above a ceiling for example.
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CA 02593674 2007-07-11
Although Figures 13 and 14 show only one gas specific DISS coupler attached to
each
fitting, it is to be understood that in these described embodiments, two gas
specific DISS
couplers may be mounted to each fitting such as shown in Figure 15. In such
embodiments, one
of the gas or vacuum specific DISS couplers may be used to connect to a
secondary gas or
vacuum source while a second one of the gas specific DISS couplers may be
mounted to a
transducer in the control panel or a second source of the same gas. Also,
although Figures 13
and 14 only show one valve in a control panel, the described fitting may be
used in control
panels with multiple valves such as that shown in Figure 4.
In addition, the described fitting may be used to provide an existing control
panel with
gas specific immediate access to withdraw medical gas from the pipeline. For
example, existing
control panels are typically located in hallway areas or at nursing stations
rather than in patient
rooms or procedure areas. Installing the described fitting with a gas specific
DISS threaded
coupler to an existing control panel enables a temporary outlet or manifolded
group of outlets
such as a medical gas rail to be quickly connected to the control panel in
order to provide
medical gases to additional patients in hallways, waiting rooms and other
areas near a control
panel.
Figure 16 shows an example of medical gas rails 500, 502 mounted to a hallway
wall 504
and adjacent a control panel 506 which includes the described fittings with
gas specific DISS
threaded couplers. These rails may include a plurality of spaced apart outlet
ports 508.
In an emergency that produces a large influx of patients, the described
medical gas rails may be
connected to the DISS threaded couplers of the control panel to provide a
supply of medical gas
to the outlet ports 508 along the medical gas rails 500, 502. Patients 514 in
a hallway or waiting
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CA 02593674 2007-07-11
room may then be positioned adjacent the rail(s) so as to quickly provide such
patients with
access to medical gases. In an exemplary embodiment, each rail is comprised of
a plurality of
parallel pipelines 510 each of which may be selectively coupled to a
respective specific gas
supply pipeline in the control panel 506. Each of the parallel pipelines of
the rail may include a
plurality of spaced apart outlet ports 508. In an emergency, gas delivery
masks 512 may be
placed in operative connection with the outlet ports to provide patients 514
with a supply of the
medical gases from the outlet ports.
The exemplary embodiment described herein include particular structures to
achieve the
desirable results. Those having skill in the art may devise other embodiments
with other
structures which employ the same inventive principles encompassed by the
subject matter as
claimed.
Thus the exemplary embodiments achieves the above stated objectives,
eliminates
difficulties encountered in the prior methods, solves problems and attains the
desirable results
described herein.
In the foregoing description certain terms have been used for brevity, clarity
and
understanding. However, no unnecessary limitations are to be implied
therefrom. Such terms
are for descriptive purposes and are intended to be broadly construed. The
descriptions and
illustrations herein are by way of examples and the invention is not limited
to the exact details
shown and described.
In the following claims any feature described as a means for performing a
function shall
be construed as encompassing any means capable of performing the recited
function. The means
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CA 02593674 2007-07-11
shall not be limited to the particular means shown as performing that function
in the foregoing
description or mere equivalents thereof.
Having described the features, discoveries and principles of embodiments, the
manner in
which it is constructed and operated, and the advantages and useful results
attained; the new and
useful structures, devices, elements, arrangements, parts, combinations,
systems, operations,
methods and relationships are set forth in the appended claims.
