Note: Descriptions are shown in the official language in which they were submitted.
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Sanitary Wash Area
Description
The invention relates to a sanitary wash area.
Acquiring infectious diseases in hospitals, so-called nosocomial
infections, represents a life-threatening situation, in
particular, for patients with a limited effective immune, system.
The transmission of pathogenic and optionally pathogenic water
germs, such as e.g. Legionnaire's and pseudomonas, acinetobacter
and klebsiella types which are found in the area of wash basins
or shower basins as well as in the bath tub or birthing tub is
hereby especially important. These are the causes of the most
important nosocomial infections (e.g. pneumonias, urinary tract
infections).
Two ways of transmitting water germs to patients and nursing
staff should be differentiated:
On the one hand, drinking water from water pipes may contain
water germs, on the other hand, the siphon trap found under the
water catch basin (wash basin, shower basin, bath tub) represents
a very large exciter reservoir and infection potential. If tap
water is used for nutritional purposes, the water germs contained
therein reach into the body of the patient by taking in
contaminated fluid.
When taking water from the water tap and draining water from the
wash basin, water germs from the drinking water reach the body
of nursing staff and patients.
While the transmission of germs by contaminated drinking water
represents a fact which has been known for a long time and
accepted in hospital hygiene, the emission of germs from the
siphon trap first came to the fore of hospital hygiene by the
works of PORING et al (1989) and SISSOKO et al (2004a and b and
2005). The emission of germs from the siphon trap was first
subjected to a quantitative analysis by DORING and was then
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placed on a broad statistic basis by SISSOKO.
Two different methods for preventing the primary germ
transmission in a moist area (wash basin, bath tub, shower)
result from the existence of two primary transmission paths for
water germs.
It is known that the transmission of germs from contaminated
drinking water is eliminated by sterile filtration of the
drinking water coming out of the line by means of a water filter
at the end. This drinking water sterilization by means of the
so-called sterile filter at the end has been part of the prior
art for a long time and introduced in high-risk areas of clinics.
Preventing the transmission of germs from the siphon trap at the
outlet of the wash basin, shower basin or bath tub first came to
be of interest to hospital hygiene from the works of SISSOKO and
colleagues (2004 and 2005).
Due to the lack of experimental data, the significance of the
siphon trap as a germ and infection reservoir was disputed by
experts to such a degree that the methods for disinfecting siphon
traps which have been proposed for several decades (US 2, 452, 387,
US 3,175,567, US 4,192,988, US 4,502,164, US 4,893,361, US
5,940,894, 6,491,814, DE 2747882, DE 4025078, DE 4206901, DE
4224445, DE 29509210, GB 1417711) were not applied in an
effective system prior to the self-disinfecting siphon trap (US
6,666,986, EP 1 159 493).
The sealing liquid of the siphon trap was well known and accepted
as a residence for germs. However, it was assumed that germs
escape through an aerosol only when a water jet from the water
pipes directly impacts the surface of the sealing liquid in the
siphon trap. This knowledge is reflected in the corresponding
hygiene regulations ("Richtlinie Krankenhaushygiene" [Hospital
Hygiene Guidelines], Elsevier, Urban & Fischer, Munich). These
regulations are still in force today. A siphon trap in which the
water jet from the tap does not directly hit this opening was
deemed hygienically safe until the year 2004. Avoiding that the
water jet from the tap directly hits the outlet opening was
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considered to be generally recognized prior art when preventing
the emission of germs from the siphon trap.
However, the results of the studies of DORING and colleagues
(1989 and 1991) and SISSOKO and colleagues (2004 and 2005) showed
that germs were emitted each time the siphon trap was used,
independent thereof whether the water jet from the tap directly
hit the basin outlet or the water flows slowly via the bottom of
the basin into the siphon trap under the outlet.
The reason for this is the high content of germs in the sealing
liquid of the siphon trap which, in turn, is caused by the
presence of the generally known slimy coating of the so-called
biofilm (SISSOKO et al, 2005).
The quantity of germs released by aerosol formation from the
siphon trap correlates with the germ density in the sealing
liquid of the siphon trap (SISSOKO et al; 2005). A study in
several clinics in Germany showed that germs were emitted from
more than 73% of all siphon traps in hospitals (SISSOKO et al;
2005).
The self-disinfecting siphon trap (US 6,666,966; EP 1 159 493)
prevents the formation of this biofilm and kills germs in the
sealing liquid. Consequently, the emission of water germs during
use of the self-disinfecting siphon trap is prevented (SISSOKO
et al, 2005).
Clinical studies for the colonization of patients by water germs
and the formation of infections before and after replacing
traditional siphon traps with the self-disinfecting siphon trap
in an interdisciplinary intensive care unit (SISSOKO et al, 2004)
showed that both the germ colonization of patients with water
germs and the occurrence of nosocomial infections were reduced
when the siphon trap was eliminated as a source of germs. With
this, it was proven for the first time that the siphon trap is
not only a residence for pathogenic water germs, but also an
active source of infections.
It is known that using only one of the two preventive measures
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for reducing germ transmission from the wash basin area has
considerable disadvantages. In practice, the disadvantages of
using only one preventive measure practised to date is so massive
that the spread of both methods, required from a hygienic point
of view, is prevented in clinics.
If, in fact, the two known preventive methods are used separately
(sterile filtration of the tap. water without the self-
disinfecting siphon trap or the self-disinfecting siphon trap
without the sterile filtration of the tap water), then only one
way for the germ transmission is interrupted in each case, while
the respectively other way remains active. This has serious
consequences: The removal and use of germ-free and pyrogen-free
tap water from a perfectly functioning sterile filter
paradoxically takes place in an aerosol cloud of bacteria from
the siphon trap (SISSOKO et al, 2004).
Furthermore, the validation of sterile filters on the end, i.e.
the proof of efficiency under all given conditions which is
required in clinical practice, is only given for very limited
periods due to the so-called retrograde germ-contamination of the
sterile filter. As a result, it is then necessary to change the
filter often. The duration of use of disposable sterile filters
(service life is usually only 5 to 7 days) is slight and the
costs are consequently very high. The reason for these short
service lives is not the quick saturation of the filter by the
retention of microorganisms, as intended, but the microbiological
contamination (described as retrograde contamination) of the open
outlet of the filter, as intended. When the outlet of the
sterile filter is sufficiently contaminated, when the sterile-
filtered drinking water passes from the sterile filter, it is
again loaded with germs which can lead to a "sterile" water that
contains substantially more germs than the drinking water prior
to the sterilization.
If the retrograde contamination is disregarded, then the end
sterile filtration has a very high efficiency in relation to the
separation of germs from the contaminated drinking water in the
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necessary and useful practical application.
In spite of the application of the end sterile filter, however,
the number of nosocomial infections due to water germs from the
moist area remains unsatisfactorily high in the everyday routine
of the clinic.
As a significant reason for this, it has just very recently been
discovered that the removal and use of germ-free tap water from
a perfectly functioning sterile filter takes place in an aerosol
with bacteria from the siphon trap (SISSOKO, et al, 2004).
When removing sterile water with simultaneous water outlet in the
siphon trap from said outlet, a fine droplet mist (aerosol) is
released from the sealing liquid inside the siphon trap which
contains the entire spectrum of germs that are found in the
sealing liquid. The aerosol can thereby contain a multiple of
the number of germs which are held back by the filtration of the
tap water. This is so dangerous because the user of the water
removal device is not aware of this danger and thus continues to
feel safe, however, this does not de facto exist until the
emission of germs from the siphon trap is also eliminated.
Cases are known from clinical practice in which, in immuno-
suppressed patients, infections that prove fatal are produced by
water germs (e.g. pseudomonas aeruginosa, klebsiella pneumoniae,
acinetobacter spezies) from the siphon trap of shower basins,
although the shower water from the shower head was subjected to
a sterile filtration.
Since - as these practice cases show - ostensible safety is more
dangerous than a recognized insecurity, from the point of view
of hygiene safety, a problematic situation arises after
installation of a sterile filter on a water tap over a siphon
trap without a disinfecting device. However, this realization
is only being accepted nowadays and very slowly in hygiene
practice.
However, the aerosol cloud from the siphon trap not only reaches
the hands of the nursing staff or patient found in the basin for
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washing and disinfection, but also the outlet of the sterile
filter. As a result, it is inoculated with water germs which
find very good reproduction conditions there, the so-called
retrograde contamination of the sterile filter begins.
Prior to the development of and the very hesitant practical
introduction of the continuous disinfection of the siphon trap
since 1997 (US 6,666,966, EP 1 159 493), the contact of the
outlet of the sterile filter with ambient air and spray water,
which occurs when water is removed or when washing the hands or
when showering under the sterile filter and directly hits or as
aerosol hits the outlet of the sterile filter, was considered the
sole cause for the retrograde contamination. The affect of the
siphon trap (siphon) found under the wash basin outlet on the
retrograde microbial colonization of the end water filter was
fully unknown and unforeseen until the year 2004.
Only the evidence of a permanent massive germ emission from the
siphon trap (SISSOKO et al, 2004) led to the realization that the
retrograde contamination of the sterile filter was caused for the
most part by the aerosols escaping from the siphon trap.
Therefore, both the validation and the desired extension of the
life of sterile filters make the elimination of the siphon trap
as an active germ source and cause of the retrograde
contamination necessary.
In contrast to the thusfar prevalent teachings that bacteria
which are found in the siphon trap are only emitted from them
under certain conditions and thus also contrary to all hygiene
practice currently practised in clinics, the ultimate evidence
of the permanent germ emission from the siphon trap and its
promoting effective in the retrograde colonization of the water
filter was provided by SISSOKO and colleagues (2004 and 2005) by
systematic broad studies.
The results of extensive microbiological and epidemic studies
show that the solution to the problem can only be obtained by the
combination of both devices. This variant represents great
progress in equipment technology in hospital hygiene and is fully
adequate for most practical applications. However, the clinical
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application situations are very different. Thus, the occurrence
and quantity of spray water and the aerosol produced from the
spray water when filling basins and tubs and in the use of shower
tubs differ substantially from the "normal" wash basin situation
in the sense of a sink for hand washing. The result of this is
that the portion of spray water and aerosols from the spray water
in the retrograde contamination differ. When filling receptacles
in which the distance between water supply and receptacle bottom
is greater than in hand-washing basins (bath tubs, birthing
tubs), the spray water portion and also the aerosol formation
resulting therefrom is greater than in relatively flat sinks.
The spray water formation is especially greater when showering.
Therefore, the retrograde contamination of the outlet of the end
sterile filter by spray water or contact can, of course, not be
eliminated by the self-disinfecting siphon trap. For this
reason, in situations in which spray water and aerosol formation
due to spray water are an important cause of retrograde
contamination, maximum sanitary safety and validation, which
cannot be exceeded by any other apparatus, are created by the
addition of a UV disinfection. The disinfection of the inner
inlet area of the self-disinfecting siphon trap by means of
ultraviolet radiation is known (US 6,666,966 Bi, EP 1 159 493 B1
and WO 00/53857). DE 92 02 902 Ui describes the use of thermal
disinfection in slack water and the destruction of germs by UV
rays in the upper area of the slack water and the inlet area of
a siphon trap found above the slack water.
The sterilization of water which flows through a sanitary device
by means of UV radiation is also known (DE 198 03 071 Al). A
shower facility with a central disinfecting unit into which UV
light is introduced into the flowing water for the sterilization
by means of a light conductor is described in DE 197 01 847 C2.
The object of the invention is to create a germ-free sanitary
wash area. This object is solved with the features of claim 1.
The installation according to the invention, which is described
as a sanitary wash area, consists, in its simplest form, of a
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wash basin or a shower basin or bath or birthing tubs (1), whose
water supplies (2) are provided with sterile filters (4) for
sterilizing tap water and whose water outlets (3) are furnished
with self-disinfecting siphon traps (5). In addition, the
sanitary wash area may be furnished with one or more UV lamps
(6), which emit ultraviolet light, for the surface disinfection
of the outlet of the sterile filter (7) and the outer area of the
inlet of the self-disinfecting siphon trap (5) as well as for the
intensive sterilization of the sink or tub surface. A device for
the spatial separation of the wash area from the surroundings,
for example, a removable or fold-away basin cover (8) ensures
that no UV radiation reaches the surroundings. Both the sterile
filter (4) and the self-disinfecting siphon trap (5) are
continuously in operation. The UV lamps (6) only work when the
wash area is not in use, optionally, only when the basin cover
(8) is closed.
The invention will now be described with reference to several
examples of embodiments.
Embodiment Example 1
The simple embodiment of the invention consists of a wash basin
(1) in which the water supply (2) is furnished with a sterile
filter (4) and the water outlet (3) with a self-disinfecting
siphon trap (5). This embodiment is shown in Figure 1 (Fig. 1).
Embodiment Example 2
The further embodiment of the invention consists of a wash basin
(1) in which the water supply (2) is furnished with a sterile
filter (4) and the water outlet (3) with a self-disinfecting
siphon trap (5). A UV lamp (6) is attached between sterile
filter (4) and water outlet (3) in such a way that the inside of
the wash basin (1), the outlet of the sterile filter (7) and the
outer inlet area of the water outlet (3) are radiated. This
variant is especially suitable for laboratories and for rooms
which are not used, e.g. during the night, because the room air
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above the wash basin is simultaneously sterilized with the
operation of the UV lamp (6). This embodiment is shown in Figure
2 (Fig. 2) .
Embodiment Example 3
A further embodiment of the invention consists of a wash basin
(1) in which the water supply (2) is furnished with an end
sterile filter (4) and the water outlet (3) with a self-
disinfecting siphon trap (5). A UV lamp (6) is attached between
sterile filter (4) and water outlet (3) in such a way that the
inside of the wash basin (1), the outlet of the sterile filter
(7) and the outer inlet area of the water outlet (3) are
radiated. The UV radiation only takes place when the basin cover
(8) is closed. If the wash basin is being used, the basin cover
(8) is removed. This embodiment is shown in Figure 3 (Fig. 3).
Embodiment Example 4
Embodiment 4 relates to a shower cabinet 'with a shower basin
(1) in which the water supply (2) is furnished with an, end
sterile filter (4) and the water outlet (3) with a self-
disinfecting siphon trap (5). The water supply (2) is in the
form of a shower head and provided with a sterile filter
(4). A UV lamp (6); is attached between sterile. filter (4) and
water outlet (3) in such a way that the inside of the shower
cabinet, the outlet of the sterile filter (7) and the shower
basin (1) with the water outlet (3) are radiated with UV light.
The shower area is provided with a partition which is
impermeable to UV rays (e.g. shower curtain or mobile partition).
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List of Drawings
Figure 1
Sanitary wash area in a simple embodiment with end sterile
filters (4) and self-disinfecting siphon trap (5).
Figure 2
Sanitary wash area in the embodiment with an end sterile filter
(4), self-disinfecting siphon trap (5) and W lamp (6) as well
as a basin cover (8) in disinfecting position. The basin cover
(8) is closed, the W lamp (6) is in operation.
Figure 3
Sanitary wash area in the embodiment with an end sterile filter
(4), self-disinfecting siphon trap (5) and W lamp (6) as well
as a basin cover (8) in operating position. The basin cover (8)
is removed, the W lamp (6) is turned off and removed from the
work area.
In another embodiment,. sanitary wash area as a shower cabinet
with a shower basin (1) in which the water supply (2) is
furnished with an end sterile filter (4) and the water outlet
(3) with a self-disinfecting siphon trap (5). In this case,
the sterile filter (4) is in the form of a shower head. A UV
lamp (6) is attached between sterile filter (4) and water
outlet (3) in such a way that the inside of the shower
cabinet, the outlet of the sterile filter (7) and the shower
basin (1) with the water outlet (3) are radiated with UV
light. The shower area is provided with a partition which is
impermeable to UV rays (e.g. shower curtain or mobile
partition).
