Self-contained emergency eye wash station

A self-contained emergency eye wash station for dispensing eye wash fluid contained in a flexible container comprises a housing, a reservoir, and a platen. The housing supports the flexible container and supports a nozzle in fluid communication with the flexible container. The nozzle dispenses the eye wash fluid from the flexible container. The housing includes a drain capturing the eye wash fluid dispensed from the nozzle. The reservoir collects the eye wash fluid captured by the drain, and the reservoir is slidably mounted to the housing. The platen is connected to the reservoir. The platen is slidably movable relative to the housing and is located immediately above the flexible container. The platen presses downward on the flexible container with a downward force proportional to a weight of the eye wash fluid collected in the reservoir. The transfer of the weight of the eye wash fluid collected in the reservoir to the platen maintains a constant flow of eye wash fluid dispensed from the nozzle.

FIELD OF THE INVENTION 
The present invention generally relates to self-contained emergency eye 
wash stations. More particularly, the present invention relates to an 
emergency eye wash station which employs a unique feedback mechanism for 
maintaining a constant flow of eye wash fluid upon actuation of the eye 
wash station and which employs a self-contained delivery system for 
maintaining long-term stability of the eye wash fluid prior to actuation 
of the eye wash station. 
BACKGROUND OF THE INVENTION 
Government and employers are increasingly aware of the need for protecting 
the health and safety of workers. For this reason, it is common to find 
eye wash fountains at industrial work stations, laboratories, and other 
locations where workers are exposed to gaseous fumes, liquids or solid 
materials which can irritate or injure eyes upon contact therewith. The 
Occupational Safety and Health Administration (OSHA) has made eye wash 
fountains mandatory for particular industrial work stations. 
Some prior art devices have employed eye wash fountains providing sprays of 
water from regular plant plumbing connections. Other prior art devices, 
such as the eye wash fountains disclosed in U.S. Pat. No. 4,012,798 to 
Liautaud and U.S. Pat. No. 4,363,146 to Liautaud, are self-contained, 
gravity-fed, and independent of any plumbing connections. Such eye wash 
fountains typically contain a reservoir (or bottle) of wash fluid spaced 
above two opposed liquid spray nozzles. Upon activating the fluid flow, 
the wash fluid from the reservoir is fed solely by gravity to the nozzles 
to cause a gravity-induced spray of wash fluid from the nozzles. 
In an effort to encourage suitable eye wash facilities, the American 
National Standards Institute (ANSI) has promulgated voluntary standards 
for portable eye wash fountains relating to flushing periods and the rate 
of flow of wash fluid. These standards dictate that portable eye wash 
fountains should deliver no less than 0.4 gallons per minute (1.5 liters 
per minute) of eye wash fluid for a time period of 15 minutes. 
A drawback of the gravity-fed eye wash fountains of the type described 
above is that they contain fluid significantly in excess of the amount 
required for actual flushing to meet the ANSI standards because the rate 
of flow of wash fluid from the gravity-fed eye wash fountains decreases 
over time. The reason for this decrease in fluid flow rate over time is 
that the fluid head height in the reservoir decreases as the wash fluid is 
dispensed from the nozzles, thereby decreasing the amount of hydraulic 
pressure on the wash fluid over time. This reduction in hydraulic pressure 
over time causes a corresponding decrease in the fluid flow rate. To 
provide 0.4 gallons per minute of wash fluid for a full 15 minutes, the 
reservoirs of gravity-fed eye wash fountains must hold a sufficient amount 
of eye wash fluid that the fluid flow rate does not drop below 0.4 gallons 
per minute prior to 15 minutes from activation. 
Another drawback of the gravity-fed portable eye wash fountains is that the 
rate of flow of wash fluid is not constant, but rather changes over time. 
The fluid flow rate is initially quite high so that the fluid flow rate 
does not drop below 0.4 gallons per minute after 15 minutes. The changes 
in fluid flow rate can limit effective flushing. 
A further drawback of gravity-fed portable eye wash fountains is they often 
waste much of the wash fluid in the reservoir (as much as 30 percent of 
the initial supply) because there is insufficient hydraulic pressure to 
force all of the wash fluid from the reservoir through the nozzles. The 
flow of wash fluid through the nozzles substantially stops after only a 
portion of the wash fluid in the reservoir has been dispensed from the 
nozzles. 
Yet another drawback of existing eye wash fountains is that they do not 
maintain the stability of the wash fluid in the reservoir for extended 
periods of time and, as a result, the wash fluid must be replaced with 
fresh wash fluid at fairly short time intervals. The fluid delivery 
systems of existing eye wash fountains generally require some exposure of 
the wash fluid in the reservoir to air. This exposure to air improves the 
flow of the wash fluid through the nozzles. At the same time, the exposure 
to air encourages the growth of bacteria existing in the wash fluid and 
the eye wash fountains themselves. The wash fluid in these eye wash 
fountains is stagnant, and at ambient temperature the environment is 
conducive to the growth of micro-organism populations. With this growth of 
bacteria, the wash fluid typically must be replaced with fresh wash fluid 
at least every six months, even when treated with preservatives. Further, 
most existing eye wash fountains employ tap water which contains chemical 
and solid particle contaminants such as chlorine, lead, and rust. The 
replacement of wash fluid is time-consuming and expensive in terms of both 
labor and materials. 
Yet a further drawback of existing eye wash fountains is that the wash 
fluid dispensed from the nozzles generally is drained onto the floor, 
resulting in a mess which must be cleaned up. Alternatively, the used eye 
wash fluid is drained into an extra floor-standing container separate from 
the eye wash fountain. The extra container, in combination with the eye 
wash fountain, occupies a large amount of space. 
An additional drawback of existing eye wash fountains is that the eye wash 
fountains typically must be removed from their operating position for 
draining of unused wash fluid, cleaning, and refilling with fresh wash 
fluid. Such removal of the eye wash fountains from their operating 
position is burdensome and time-consuming. When refilled and ready to be 
returned to their operating position, the units often weigh in excess of 
130 pounds. 
A need therefore exists for a self-contained eye wash station which 
overcomes the aforementioned shortcomings associated with existing 
portable eye wash fountains. 
SUMMARY OF THE INVENTION 
In one aspect of the present invention, a self-contained emergency eye wash 
station for dispensing eye wash fluid contained in a flexible container 
comprises a housing, a reservoir, and a platen. The housing supports the 
flexible container and supports a nozzle in fluid communication with the 
flexible container. The nozzle dispenses the eye wash fluid from the 
flexible container. The housing includes a drain capturing the eye wash 
fluid dispensed from the nozzle. The reservoir collects the eye wash fluid 
captured by the drain, and the reservoir is slidably mounted to the 
housing. The platen is connected to the reservoir. The platen is slidably 
movable relative to the housing and is located immediately above the 
flexible container. The platen presses downward on the flexible container 
with a downward force proportional to a weight of the eye wash fluid 
collected in the reservoir. The transfer of the weight of the eye wash 
fluid collected in the reservoir to the platen maintains a constant flow 
of eye wash fluid dispensed from the nozzle. 
In another aspect of the present invention, the emergency eye wash station 
employs a self-contained delivery system comprising a flexible container 
containing an eye wash fluid, a nozzle, a seal element, and an actuation 
element. The nozzle is in fluid communication with the container and is 
detachably connectable to a housing of the eye wash station. The nozzle 
includes an upper pressure plate and a lower nozzle body. The lower nozzle 
body forms an inlet for receiving the eye wash fluid from the container 
and forms a plurality of apertures in fluid communication with the inlet. 
The upper pressure plate is detachably linked to the lower nozzle body. 
The seal element is removably coupled to the nozzle. The seal element 
firmly secures the upper pressure plate to the lower nozzle body such that 
the upper pressure plate blocks the apertures formed in the lower nozzle 
body. The actuation element is coupled to the seal element. The 
self-contained delivery system is able to maintain long-term stability of 
the eye wash fluid.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Turning now to the drawings, FIGS. 1-7 illustrate a self-contained 
emergency eye wash station 10 used to dispense eye wash fluid contained in 
a pair of flexible containers. FIG. 1 is an exploded view depicting 
various components of the eye wash station 10, including a housing 12, a 
pair of platens 14, a cover 16, an actuation door 18, and a reservoir 46. 
In addition to the foregoing components, the eye wash station 10 includes 
a self-contained eye wash fluid delivery system having a pair of identical 
delivery arrangements. One of these delivery arrangements is best shown in 
FIG. 18 prior to installation in the housing 12. The delivery arrangement 
in FIG. 18 includes a box 20, a flexible container 21 holding eye wash 
fluid, a nozzle 22, and a hose 24. FIGS. 2-6 illustrate the sequence of 
preparing the eye wash station 10 for use, and FIG. 7 illustrates the eye 
wash station 10 after it has been activated. Briefly, in this sequence of 
preparing the eye wash station 10 for use, the platens 14 are raised from 
a lower position in FIG. 2 to an upper position in FIG. 3. The platens 14 
are temporarily locked in this upper position using a latching mechanism 
described in detail below. With the platens 14 locked in the upper 
position, the fluid delivery system is loaded into the housing 12 as shown 
in FIG. 4. Next, the cover 16 is slidably mounted to the housing 12 (FIG. 
5), and the hinged actuation door 18 is rotated to a closed position (FIG. 
6). Mounting the cover 16 to the housing 12 actuates the latching 
mechanism to release the platens 14 from their locked upper position and 
cause the platens 14 to drop onto the fluid-filled flexible containers 21 
of the fluid delivery system. To activate the eye wash station, the 
actuation door 18 is rotated to the open position in FIG. 7. The 
construction and operation of the eye wash station 10 are described in 
detail below. 
A top of the housing 12 is provided with a handle 25 for mounting the eye 
wash station 10 to a vertical wall or mobile cart in an industrial work 
station, laboratory, or other location where workers are exposed to 
gaseous fumes, liquids or solid materials which can irritate or injure 
eyes upon contact therewith (FIGS. 2-4). The vertical wall or mobile cart 
is preferably provided with a conventional J-hook (not shown) supporting 
the handle 25. The top wall of the cover 16 is preferably curved to 
discourage individuals from laying loose items on the cover 16 which could 
contaminate the eye wash station 10 (FIGS. 1, 5, 6, and 7). 
The housing 12 supports the boxes 20 holding the respective flexible 
containers 21 and supports the nozzles 22 interconnected to the flexible 
containers 21 via the hoses 24 (FIG. 4). To support the boxes 20, the 
housing 12 forms a rigid shelf 26 of sufficient width and depth to 
accommodate the pair of boxes 20 in side-by-side relation to one another 
(FIGS. 1, 3, and 4). In addition to supporting the bottoms of the boxes 
20, the housing 12 provides side walls 28 to support the outer sides of 
the boxes 20 and a vertical rear wall 30 to support the back sides of the 
boxes 20 (FIG. 4). The side walls 28 are preferably spaced from each other 
by a distance only slightly greater than the combined width of the boxes 
20 so that the boxes 20 snugly fit between the side walls 28. By virtue of 
this snug fit, the inner sides of the boxes 20 abut each another so that 
the boxes 20 provide each other with mutual support. 
When the cover 16 is slidably mounted to the housing 12 as shown in FIGS. 6 
and 7, the front wall of the cover 16 combines with the rear wall 30 (FIG. 
4) of the housing 12 to support the respective front and back sides of the 
boxes 20. Referring to FIG. 17, the front wall of the cover 16 and the 
rear wall 30 of the housing 12 are preferably spaced from each other by a 
distance only slightly greater than the depth of the boxes 20 so that the 
boxes 20 snugly fit between the front wall of the cover 16 and the rear 
wall 30 of the housing 12. Thus, each of the boxes 20 is supported on its 
four vertical sides and its bottom. As will become apparent, this support 
is desired during operation of the eye wash station 10 to prevent bulging 
of the boxes 20 as the platens 14 press downward on the flexible 
containers 21 within the respective boxes 20. By supporting the sides of 
the boxes 20, the eye wash fluid in the flexible containers 21 is forced 
by the platen pressure out of the flexible containers 21 within the 
respective boxes 20 to the respective nozzles 22. In an alternative 
embodiment, the flexible containers 21 are loaded into the housing 12 
without the surrounding boxes 20. To provide the loose containers 21 with 
support, the housing 12 includes a vertical front wall extending between 
the side walls 28. This front wall extends upwardly from the shelf 26 to 
the platens 14 when the platens 14 are in their upper position. Using this 
front wall, the housing 12 serves substantially the same support function 
as the boxes 20. The front wall may be hinged to the front edge of the 
shelf 26 to allow the front wall to be rotated downward to a horizontal 
position and permit front-loading of the flexible containers 21 into the 
housing 12. Alternatively, the platens 14 may be rotatable from their 
normal horizontal orientation to a vertical orientation to permit 
top-loading of the containers 21 into the housing 12. 
To support the nozzles 22, the housing 12 includes a frontal nozzle mount 
32 having a pair of elongated slots 34 formed therein (FIG. 1-3). These 
slots 34 cooperate with opposing grooves 36 (FIG. 8) formed in each nozzle 
22 to slidably engage the nozzles 22 in the respective slots 34 (FIGS. 4, 
5, and 7). This sliding engagement of the nozzles 22 in the respective 
slots 34 positively locates the nozzles 22 with respect to the housing 12. 
The width of each slot 34 is approximately the same as the width of each 
nozzle 22 in the region of the grooves 36 (FIG. 8) to create a fairly snug 
fit therebetween. To engage the nozzles 22 in the respective slots 34, the 
nozzles 22 are first positioned adjacent the outermost edges of the 
respective slots 34 (i.e., left edge of the left slot 34 and right edge of 
the fight slot 34 in FIGS. 1-3). Next, with the opposing grooves 36 (FIG. 
8) of each nozzle 22 aligned with the opposing elongated edges of each 
respective slot 34, the nozzles 22 are slid inwardly through the 
respective slots 34 with the opposing grooves 36 of each nozzle 22 
slidably receiving the opposing elongated edges of each respective slot 
34. 
During the operation of the eye wash station 10, the nozzles 22 dispense 
the eye wash fluid contained in the respective flexible containers 21 
within the boxes 20 (FIG. 18). The eye wash fluid dispensed from the 
nozzles 22 is captured in a basin 44 having a floor properly sloped to 
direct the eye wash fluid to a drain 38 (FIGS. 7 and 17). The drain 38 
includes a pair of holes formed on opposite sides of the frontal nozzle 
mount 32. The eye wash fluid captured on the floor of the basin 44 flows 
backward around the nozzle mount 32 to the holes of the drain 38. 
The eye wash fluid captured by the drain 38 is conveyed by the drain 38 to 
the reservoir 46. As best shown in FIGS. 1 and 17, the reservoir 46 
includes a tank 48 of sufficient size to hold the volume of eye wash fluid 
contained in the flexible containers 21 within the boxes 20. The upper 
surface of the tank 48 forms a rectangular opening 50 to receive the eye 
wash fluid exiting the drain 38. The eye wash fluid flows through the 
holes of the drain 38 with sufficient velocity that the fluid is propelled 
into the rectangular opening 50 (FIG. 17). In an alternative embodiment, 
the drain 38 includes a pair of pipes extending from the respective drain 
holes to the rectangular opening 50 in the tank 48. 
The bottom of the housing 12 is completely open to permit the tank 48 to 
extend upward into the housing 12 (FIGS. 2-7 and 17). When the tank 48 is 
empty prior to using the eye wash station 10, the housing 12 conceals a 
substantial portion of the tank 48 (FIG. 6). The tank 48 moves downward 
relative to the stationary housing 12 in response to the tank 48 
collecting the eye wash fluid therein (FIG. 17). As more and more eye wash 
fluid enters the tank 48, the more the tank 48 is exposed beneath the 
housing 12. When the tank 48 is substantially filled with the eye wash 
fluid following use of the eye wash station 10, the tank 48 is 
substantially exposed (see FIG. 2). 
When the eye wash station 10 is mounted to a vertical wail or mobile cart 
in an industrial work station, laboratory, or the like, the eye wash 
station 10 is mounted at such a height that the tank 48 will not contact 
the floor or ground prior to being substantially filled with the eye wash 
fluid. The lower surface of the tank 48 is preferably curved to encourage 
proper mounting of the eye wash station 10 to a vertical wall. With this 
curved lower surface, the eye wash station 10 will not remain upright if 
it is allowed to stand freely on the floor or ground. 
To stabilize the vertical movement of the tank 48 relative to the housing 
12 so as to minimize lateral shifting of the tank 48 relative to the 
housing 12, the transverse cross-section of the tank 48 is substantially 
identical in shape to the transverse cross-section of the lowermost 
portion of the housing 12 (FIGS. 1-7). Moreover, the transverse 
cross-section of the tank 48 is only slightly smaller in size than the 
transverse cross-section of the lowermost portion of the housing 12. Thus, 
a tight tolerance exists between the housing 12 and the tank 48. 
The reservoir 46 further includes a rear support 52 extending upward from a 
rear portion of the tank 48 (FIGS. 1 and 17). As best shown in FIG. 17, 
the rear support 52 extends into the housing 12 between the rear wall 30 
and a second rear wall 54 parallel to the rear wall 30. The rear walls 30 
and 54 define a narrow cavity in the housing 12 for receiving the rear 
support 52 of the reservoir 46. As the reservoir 46 moves vertically 
relative to the housing 12, the rear support 52 slides vertically through 
the cavity. To ensure smooth movement of the reservoir 46 relative to the 
housing 12, the width and thickness of the rear support 52 are only slight 
smaller than the corresponding dimensions of the cavity. In accordance 
with the vertical movement of the tank 48, the rear support 52 slides 
vertically downward through the cavity as the tank 48 collects the eye 
wash fluid therein. 
The platens 14 are mounted to the rear support 52 of the reservoir 46 by 
respective elongated members 56 (FIGS. 1 and 17). The elongated members 56 
are connected to the rear support 52 by conventional means such as a 
quarter-turn lock. The platens 14 are vertically movable between an upper 
and lower position in response to corresponding vertical movement of the 
reservoir 46. To permit vertical movement of the platens 14, the rear wall 
30 of the housing 12 is provided with a pair of vertical guide slots 58. 
The elongated members 56 extend from the interior of the housing 12, 
through the respective guide slots 58, and to the rear support 52 of the 
reservoir 46 (FIG. 17). Thus, as the platens 14 move between the upper and 
lower position, the elongated members 56 move vertically through the 
respective guide slots 58. 
When the boxed flexible containers 21 are loaded into the housing 12, the 
platens 14 are located immediately above the flexible containers 21 (FIGS. 
4, 17, and 20). As described below, the platens 14 are responsible for 
maintaining a constant flow of the eye wash fluid dispensed from the 
nozzles 22. The platens 14 press downward on the flexible containers 21 in 
the respective boxes 20 with a downward force proportional to a weight of 
the eye wash fluid collected in the reservoir 46. Therefore, the greater 
the volume of eye wash fluid in the reservoir 46, the greater the downward 
force that the platens 14 apply to the flexible containers 21. 
More specifically, as the eye wash fluid from the flexible containers 21 is 
dispensed from the nozzles 22, captured by the drain 38, and collected in 
the tank 48 of the reservoir 46, the weight of this collected eye wash 
fluid is essentially transferred by the reservoir 46 to the platens 14 
(FIG. 17). The reservoir 46 pulls downward on the platens 14 with a force 
approximately equal to the combination of the weight of the reservoir 46 
and the weight of the collected eye wash fluid. Since the platens 14 are 
located immediately above the flexible containers 21 within the respective 
boxes 20, pulling downward on the platens 14 causes the platens 14 to 
press downward on the flexible containers 21 with a force equivalent to 
the aforementioned weight combination. This downward force maintains a 
constant flow of the eye wash fluid from the nozzles 22. Thus, the 
reservoir 46 and the platens 14 serve as a feedback mechanism using the 
weight of the collected eye wash fluid to apply downward force to the 
flexible containers 21. 
Prior to using the eye wash station 10, the eye wash fluid delivery system 
is loaded into the housing 12. The delivery system includes a pair of 
identical delivery arrangements, one of which is best shown in FIG. 18. 
Each delivery arrangement includes the flexible container 21 within the 
box 20, the nozzle 22, and the flexible hose 24 interconnecting the nozzle 
22 to the flexible container 21. Each of the foregoing components of the 
delivery arrangement is described in detail below. 
The box 20, shown in detail in FIGS. 18 and 19, contains the flexible 
container 21 substantially filled with eye wash fluid. The eye wash fluid 
is preferably a purified fluid such as a buffered isotonic saline 
solution, although it could be as simple as purified water. An exemplary 
solution is eyesaline.RTM. manufactured by Fendall Company of Arlington 
Heights, Ill. Alternatively, the purified eye wash fluid may have a 
special composition directed toward certain types of hazards. The flexible 
container 21 is preferably a metallized MYLAR.TM. bag including a layer of 
polyethylene. The box 20 is preferably composed of corrugated plastic or 
thick-walled corrugated paperboard. If the box 20 is composed of 
corrugated paperboard, the paperboard is preferably wax-coated to protect 
the box 20 against such environmental conditions as humidity. The box 20 
includes opposing front and back walls 60 and 62, opposing side walls 64 
and 66, and a bottom wall 68. To safeguard the flexible container within 
the box 20 during shipment thereof, the box 20 may also be provided with a 
temporary top wall (not shown). This top wall is removed prior to 
installation of the box 20 into the housing 12. 
The back wall 62 of the box 20 includes a removable tear strip 70 extending 
downward from the upper edge thereof (FIG. 19). Like the top wall, the 
tear strip 70 safeguards the flexible container during shipment thereof 
and is removed prior to installation of the box 20 into the housing 12. 
Removing the tear strip 70 provides the back wall 62 of the box 20 with an 
elongated vertical clearance slot. This clearance slot is laterally 
positioned along the back wall 62 such that, following installation of the 
box 20 into the housing 12, the clearance slot is aligned with a 
respective one of the guide slots 58 formed in the rear wall 30 of the 
housing 12 (FIG. 4). When the elongated members 56 of the respective 
platens 14 extend through the respective guide slots 58, they also extend 
through the clearance slots in the back walls 62 of the respective boxes 
20. As the elongated members 56 move vertically through the respective 
guide slots 58, they simultaneously move vertically through the clearance 
slots in the respective boxes 20. 
The lower portion of the front wall 60 of the box 20 forms a hole sized to 
accommodate an outlet fitment 72 (FIG. 18). One end of the flexible hose 
24 is firmly connected to this outlet fitment 72. The other end of the 
flexible hose 24 is firmly connected to an inlet fitment 74 on the nozzle 
22. In the preferred embodiment, the hose 24 has an inner diameter of 
approximately 0.38 inches (0.95 cm). 
Referring now to FIGS. 8-15, each nozzle 22 includes an upper pressure 
plate 76 and a lower nozzle body 78. The lower nozzle body 78 includes the 
inlet 74, a distribution manifold 80 (FIG. 12), and an elongated array of 
apertures 82 (FIGS. 14 and 15). The distribution manifold 80, which 
receives eye wash fluid from the inlet 74, distributes the eye wash fluid 
to the apertures 82. The array of apertures 82 in the lower nozzle body 78 
preferably includes approximately sixteen apertures arranged in two rows 
of eight apertures per row (FIGS. 14 and 15). To permit the nozzle 22 to 
be slidably mounted to the elongated slots 34 formed in the frontal nozzle 
mount 32 of the housing 12, the lower nozzle body 78 is provided with the 
opposing grooves 36. 
Prior to activation of the eye wash station 10, the upper pressure plate 76 
is hingedly connected to the lower nozzle body 78. In particular, the 
upper pressure plate 76 forms a retaining tab 84 which is releasably held 
in a slot 85 formed in the lower nozzle body 78 (FIGS. 12-15). A seal 
element, such as a plastic shrink band 86, is used to firmly secure the 
upper pressure plate 76 to the lower nozzle body 78 such that the upper 
pressure plate 76 blocks the apertures 82 formed in the lower nozzle body 
78 (FIGS. 8 and 10). The shrink band 86 tightly circumscribes the nozzle 
22 at an opposite end of the nozzle 22 relative to the hinged connection 
of the pressure plate 76 and nozzle body 78. To hermetically seal the 
output ends of the apertures 82 prior to activation of the eye wash 
station 10, the upper pressure plate 76 forms an elongated pocket 88 (FIG. 
13) which accommodates a rubber gasket 90 (FIG. 12). As best shown in FIG. 
12, the gasket 90 presses against the apertures 82 to prevent air flow 
into the apertures and to prevent any possible leakage of the eye wash 
fluid therefrom. 
To permit separation of the upper pressure plate 76 from the lower nozzle 
body 78, a flexible actuation strap 92, composed of a flexible polymeric 
material, woven fabric, or the like, is fixedly adhered or mechanically 
fastened to the upper surface of the upper pressure plate 76 (FIGS. 8, 9, 
10, and 12). The strap 92 extends from the hinged end to the wrapped end 
of the upper pressure plate 76 or, alternatively, the strap 92 extends 
only from a middle portion of the upper pressure plate 75 to the wrapped 
end thereof. Moreover, the strap 92 passes beneath the shrink band 86 
between the upper surface of the pressure plate 76 and the inner surface 
of the shrink band 86 (FIG. 8). The strap 92 is not adhered to the upper 
surface of the pressure plate 76 in the region beneath the shrink band 86. 
The manner in which this strap 92 is used to separate the upper pressure 
plate 76 from the lower nozzle body 78, and thereby permit eye wash fluid 
to be dispensed from the lower nozzle body 78 via the apertures 82, is 
described in detail below. 
Until the eye wash station 10 is activated, the eye wash fluid delivery 
system is a hermetically sealed system extending from the flexible 
containers 21, through the respective hoses 24, to the nozzles 22 (FIGS. 4 
and 18). This sealed delivery system prevents any contamination of the eye 
wash fluid passageway formed by the containers 21, the hoses 24, and the 
nozzles 22. The eye wash fluid in the sealed delivery system is not 
exposed to the environment. Moreover, the sealed delivery system maintains 
the stability of the eye wash fluid contained in that fluid passageway for 
a time period as long as approximately 2-3 years. Such long-term stability 
of the eye wash fluid is advantageous because if the eye wash station 10 
goes unused, its unused delivery system need not be replaced with a new 
delivery system for 2-3 years. As a result, the maintenance required by 
the eye wash station 10 during long-term periods of nonuse is minimal. 
To load the eye wash fluid delivery system into the housing 12, the cover 
16 is slidably detached from the housing 12 so that the eye wash station 
10 appears as in FIG. 2. Next, the pair of platens 14 are vertically moved 
to their upper position depicted in FIG. 3 if the platens 14 are not 
already in that upper position. 
Referring now to FIGS. 1 and 16a-c, to maintain the platens 14 in the upper 
position without requiring an operator to hold the platens 14 in the upper 
position, a pair of platen-release latches 94 are formed by a deflectable 
outer upper portions of the outer rear wall 54 of the housing 12. The 
outer upper portions of the rear support 52 of the reservoir 46 form 
mating catches 96 (FIG. 1). FIGS. 16a-c are cross-sectional views of the 
eye wash station, taken through a lower central portion of the eye wash 
station and then jogging outward from this lower central portion to an 
upper, laterally outward portion of the eye wash station. This lower 
central portion is taken along a vertical plane of mirror symmetry passing 
through the center of the tank 48 and the centers of the respective basin 
44 and nozzle mount 32 of the housing 12. The upper, laterally outward 
portion is taken along a vertical plane passing through one of the latches 
94 and its associated catch 96. 
When the platens 14 are moved to the upper position, each catch 96 serves 
as a cam which communicates motion to the associated latch 94, which 
serves as a cam follower. The catch 96 deflects the latch 94 clockwise (as 
viewed in FIGS. 16a-c) from its relaxed position until an edge 96a of the 
catch 96 advances beyond an edge 94a of the latch 94. At this point, the 
latch 94 springs back to its relaxed position with the edge 96a of the 
catch 96 engaging the edge 94a of the latch 94 (FIG. 16a). Since the 
platens 14 are mounted to the rear support 52 by the elongated members 56, 
engagement of the catches 96 by the respective latches 94 holds the 
platens 14 in their upper position. 
With the platens 14 in their upper position, the boxes 20 holding the 
flexible containers 21 are placed within the housing 12 on the shelf 26 
beneath the respective platens 14. Moreover, the nozzles 22 are mounted to 
the frontal nozzle mount 32 by slidably engaging the grooves 36 formed in 
the lower nozzle body 78 of each nozzle 22 with the respective slots 34 
formed in the nozzle mount 32. 
After installing both the boxes 20 and the nozzles 22 into the housing 12, 
the cover 16 is slidably mounted to the housing 12 (FIG. 5). The housing 
12 preferably forms a vertical track for receiving the sliding cover 16. 
The cover 16 and the housing 12 form respective engaging portions, such as 
mating male and female nubs, for holding the cover 16 in the closed 
position. While closing the cover 16, the hoses 24 are fed through 
respective hose clearance notches 40 formed in the lower edge of the cover 
16. 
Referring to FIGS. 16a-c, the cover 16 is preferably designed to 
automatically disengage each platen-release latch 94 from the associated 
catch 96 upon closure thereof. The cover 16 forms a downwardly-extending 
rear tab 97. Mounting the cover 16 to the housing 12 causes the tab 97 to 
deflect the latch 94 clockwise until the edge 94a of the latch 94 no 
longer supports the edge 96a of the catch 96, thereby releasing the rear 
support 52 (FIG. 16c). Since the platens 14 are connected to the rear 
support 52, disengaging the rear support 52 releases the platens 14 from 
their upper position so that the platens 14 drop onto the flexible 
containers 21 within the respective boxes 20 (FIG. 4). The boxes 20 are 
sized to accommodate the respective platens 14 therein while providing 
minimal space between the peripheries of the platens 14 and the vertical 
walls 60, 62, 64, and 66 of the respective boxes 20. In an alternative 
embodiment, buttons are mounted to the housing 12 and coupled to the 
respective latches 94. Prior to mounting the cover 16 to the housing 12, 
the buttons are depressed to disengage the latches 94 from the respective 
catches 96. 
After mounting the cover 16 to the housing 12, the straps 92 are laid out 
to the sides (FIG. 5). Next, the actuation door 18 is rotated to its 
closed position (FIG. 6). While closing the actuation door 18, the straps 
92 are pulled about opposing sides of the actuation door 18. The opposing 
sides of the actuation door 18 form locating notches 100 for receiving the 
respective straps 92 (FIGS. 5 and 6). With the actuation door 18 closed 
and the straps 92 passing through the respective notches 100, the loose 
ends of the straps 92 are fastened to the actuation door 18 by detachable 
fastening means. In one embodiment, the detachable fastening means 
includes male fasteners 101 attached to the ends of the straps 96 and 
holes 103 formed in the actuation door 18 slightly inward from the notches 
100. The male fasteners 101 form barbs to firmly secure these fasteners 
within the respective holes 103. The length of the straps 92 is selected 
such that the straps 92 are sufficiently slack to avoid placing undue 
stress on the shrink bands 86, and yet are sufficiently taut to fit within 
the notches 100 formed in the opposing sides of the door 18 so that 
slippage is not a problem when the eye wash station 10 is activated. The 
eye wash station 10 is now ready for operation in the event of an 
emergency requiring a user to flush his or her eyes. Prior to such an 
emergency, the actuation door 18 serves as a dust cover protecting the 
nozzles 22 and basin 44 from contaminants in the environment. 
In response to an emergency requiring immediate eye flushing, the user 
opens the actuation door 18 by grasping onto its integrally-formed handle 
102 and pulling the actuation door 18 via the handle 102 to its open 
position (FIG. 7). Opening the actuation door 18 activates the flow of the 
eye wash fluid from the nozzles 22 by pulling the straps 92 relative to 
the respective nozzles 22. More specifically, opening the actuation door 
18 pulls each strap 92 in a direction countering the force applied by the 
associated shrink band 86 to the nozzle 22 (FIGS. 8-10). Pulling the 
actuation strap 92 first breaks the shrink band 86, and continued pulling 
of the strap 92 rotates the pressure plate 76 upward about the hinged 
connection between the pressure plate 76 and the nozzle body 78 (FIG. 11). 
As the actuation door 18 reaches its open position (FIG. 7), the retaining 
tab 84 (FIG. 13) of each upper pressure plate 76 is dislodged from its 
slot 85 (FIG. 15) in the associated lower nozzle body 78 to completely 
separate the pressure plate 76 from the nozzle body 78. 
When the actuation door 18 is in its open position, the pressure plates 76 
hang from the actuation door 18 by virtue of their attachment to the 
straps 92 which, in turn, are fastened to the actuation door 18 (FIG. 7). 
The lower nozzle bodies 78 of the respective nozzles 22 remain engaged in 
the slots 34 formed in the frontal nozzle mount 32 of the housing 12. 
With the pressure plates 76 separated from their respective lower nozzle 
bodies 78, the eye wash fluid from the flexible containers 21 is dispensed 
from the lower nozzle bodies 78 via the apertures 82 (FIG. 15). Each 
aperture 82 provides a separate stream of eye wash fluid. The user flushes 
his or her eyes by bending over and positioning his or her eyes over the 
dispensed streams of eye wash fluid. The left eye is flushed with the 
streams emitted from the left nozzle body, while the fight eye is flushed 
with the streams emitted from the fight nozzle body. While flushing his or 
her eyes, the user typically leans on the eye wash station 10 for balance 
and support by placing his or her elbows on right and left arms 105a, 105b 
(FIG. 7) of the housing 12. The user holds his or her eyes open with his 
or her fingers to permit flushing thereof. 
To prevent the emitted streams from falling back on the apertures 82 in the 
nozzle bodies 78, the streams are emitted from the lower nozzle bodies 78 
at a slight forward angle relative to the vertical direction (FIG. 17). In 
the preferred embodiment, this angle is approximately eight degrees 
relative to the vertical direction. Moreover, to minimize wicking between 
the multiple streams dispensed from each nozzle body 78, the upper surface 
of each nozzle body 78 forms an array of nipples or standoffs 104 (FIGS. 
11 and 15). The apertures 82 extend through the respective nipples 104 so 
that the streams are emitted from the lower nozzles bodies 78 via the 
nipples 104. In the preferred embodiment, the nipples 104 extend 
approximately 0.063 inches (1.6 mm) above the flat portion of the upper 
surface of the associated nozzle body 78. Since the apertures 82 are 
arranged in an elongated array (FIGS. 14 and 15), the streams of eye wash 
fluid emitted from each nozzle body 78 form an elongated ribbon-like 
pattern. It has been found that this elongated pattern provides better 
coverage to the eyes of the user than nozzles having apertures arranged in 
a circular array. 
As described previously, the eye wash fluid dispensed from the nozzles 22 
is captured by the drain 38 which, in turn, directs the captured eye wash 
fluid to the opening 50 in the tank 48 of the reservoir 46 (FIG. 17). As 
the eye wash fluid is collected in the tank 48, the weight of the 
collected eye wash fluid is transferred to the platens 14 via the rear 
support 52 of the reservoir 46. The platens 14 apply a downward force to 
the respective flexible containers 21 proportional to the weight of the 
eye wash fluid collected in the tank 48. Since the volume of the collected 
eye wash fluid steadily increases over time, the weight of the collected 
eye wash fluid steadily increases over time and the downward force applied 
by the platens 14 to the respective flexible containers 21 steadily 
(linearly) increases over time. This downward force keeps the height of 
the fluid spray pattern and the flow of the eye wash fluid dispensed from 
the nozzles 22 constant over time until minimal fluid remains in the 
flexible containers 21. 
The flexible containers 21 contain a sufficient volume of the eye wash 
fluid so that the nozzles 22 deliver no less than 0.4 gallons per minute 
(1.5 liters per minute) of eye wash fluid for a time period of 15 minutes. 
In the preferred embodiment, the fluid flow rate is approximately 0.45 
gallons per minute, and the flow rate does not fluctuate from this value 
until the flexible containers 21 substantially run out of the eye wash 
fluid. The eye wash station 10, including the size of the flexible 
containers 21 and the pressure applied by the platens 14, can be modified 
to achieve a different flow rate for a different time period in order to 
satisfy any changes in the standards for eye wash stations. 
As the eye wash fluid is dispensed from the flexible containers 21, the 
platens 14 move vertically downward from their upper position toward their 
lower position. When substantially all the eye wash fluid has been 
dispensed from the flexible containers 21, the platens 14 are in their 
lower position and the emergency use of the eye wash station 10 has been 
completed. 
To prepare the eye wash station 10 for another potential emergency, service 
personnel discard the waste fluid collected in the tank 48, discard the 
used eye wash fluid delivery system, and load a fresh eye wash fluid 
delivery system into the housing 12. To remind the service personnel that 
the used eye wash station 10 is in need of servicing, the tank 48 is 
preferably printed with such language as "UNIT DISCHARGED" or "UNIT 
DISCHARGED--SERVICE IMMEDIATELY" (FIGS. 1 and 2). This language is hidden 
by the housing 12 prior to use of the station 10 (FIG. 6), but is exposed 
following use of the station 10. 
To discard the waste fluid collected in the tank 48, the tank 48 is 
provided with an integral valve 106 at its lower end for draining the 
waste fluid from the tank 48 into a conventional waste container 
positioned beneath the tank 48 (FIGS. 1-7). Opening the valve 106 permits 
the waste fluid to empty into the waste container. To prevent the service 
personnel from forgetting to close the valve 106 after emptying the waste 
fluid from the tank 48, the valve 106 may be a self-closing valve. If the 
valve 106 is self-closing, the service personnel must hold the valve 106 
while draining the waste fluid from the tank 48. Alternatively, the valve 
106 may be designed with a lever which only permits the tank 48 to be 
lifted upward into the housing 12 when the lever is in the closed 
position. When the valve 106 is in the open position, the lever interferes 
with the housing 12 when the service personnel attempt to raise the tank 
48 upward into the housing 12. When the valve 106 is in the closed 
position, the lever clears the housing 12 when the tank 48 is lifted 
upward. 
To discard the used eye wash fluid delivery system, the cover 16 is 
slidably removed from the housing 12 to permit access to the interior of 
the housing 12. Next, the tank 48 is lifted upward into the housing 12 
until the latches 94 engage the respective catches 96 in the rear support 
52. Since the tank 48 is connected to the platens 14 via the rear support 
52, lifting the tank 48 effectively moves the platens 14 from their lower 
position to their upper position. Engagement of the catches 96 by the 
respective latches 94 maintains the platens 14 in their upper position. 
The lower nozzle bodies 78 of the nozzles 22 are then slidably disengaged 
from their respective slots 34, and the straps 92 are disconnected from 
the actuation door 18 to detach the upper pressure plates 76 of the 
nozzles 22 from the door 18. After detaching the engageable components of 
the used delivery system from the housing 12, all the components of the 
used delivery system, including the boxes 20, the substantially empty 
flexible containers 21, the hoses 24, the upper pressure plates 76, the 
lower nozzle bodies 78, and the straps 92, are discarded. 
After discarding the used delivery system, a fresh (unused) eye wash fluid 
delivery system is loaded into the housing 12 (FIGS. 4-6). Since the 
procedure for loading the delivery system into the housing 12 is described 
above, it will not be repeated in detail herein. It suffices to state that 
new boxes 20 holding new flexible containers 21 containing fresh eye wash 
fluid are placed within the housing 12 on the shelf 26 beneath the 
respective platens 14, and new nozzles 22 are slidably mounted to the 
frontal nozzle mount 32. Next, the cover 16 is mounted to the housing 12 
to disengage the latches 94 from the respective catches 96 and cause the 
platens 14 to drop onto the new flexible containers 21. Finally, the 
actuation door 18 is closed, and new straps 92 extending from the new 
nozzles 22 are fastened to the actuation door 18. The eye wash station 10 
is now ready for emergency use. 
The eye wash station 10 is manufactured using conventional plastic molding 
techniques. For example, the housing 12, the platens 14, the cover 16, and 
the actuation door 18 are composed of plastic and are manufactured using 
conventional rotational molding or blow molding techniques. The nozzles 22 
are composed of molded plastic and are manufactured using conventional 
injection molding techniques. The straps 92 are preferably labelled with a 
batch identification number and an expiration date to provide a means for 
informing the user of the freshness of the eye wash fluid in the flexible 
containers 21. 
While the present invention has been described with reference to one or 
more particular embodiments, those skilled in the art will recognize that 
many changes may be made thereto without departing from the spirit and 
scope of the present invention. 
For example, the pair of platens 14 may be replaced with a single large 
platen attached to the rear support 52 of the reservoir 46 by one or more 
elongated members akin to the elongated members 56. These elongated 
members extend through corresponding vertical slots formed in the rear 
wall 30 of the housing 12, where the vertical slots permit vertical 
movement of the elongated members relative to the housing 12. In this 
embodiment, the pair of boxes 20 containing the respective flexible 
containers 21 are replaced with a single box containing a single flexible 
container. If a single flexible container is employed, the pair of nozzles 
22 may be replaced with a single elongated nozzle slidably mounted to a 
single elongated slot formed in the frontal nozzle mount 32 of the housing 
12. This single nozzle is interconnected to the single flexible container 
by a single flexible hose. 
Furthermore, other pressure application techniques may be used to maintain 
pressure on the flexible containers 21 and thereby maintain a constant 
flow of the eye wash fluid dispensed from the nozzles 22. FIG. 21a, for 
example, schematically depicts a spring-lifted support method where the 
flexible containers 21 are raised as the eye wash fluid is dispensed 
therefrom. The flexible containers 21 sit on a movable shelf 108 hanging 
from a stationary top wall 110 by extension springs 112. The springs 112 
force the shelf 108 upward, and the shelf 108, in turn, presses the 
flexible containers 21 against the stationary top wall 110. Raising the 
shelf 108 upward as the fluid is dispensed from the flexible containers 21 
maintains the head height of the fluid at its initial level relative to 
the nozzles, thereby maintaining a constant fluid flow rate. FIG. 21b 
schematically depicts a gas cylinder-lifted support method where the 
extension springs 112 in FIG. 21a are replaced with gas cylinders 114 
which force the shelf 108 upward so that the shelf 108 presses the 
flexible containers 21 against the stationary top wail 110. Once again, 
the fluid head height is maintained at a constant level relative to the 
nozzles. FIG. 21c schematically depicts a spring-lifted hinged shelf 
method where the flexible containers 21 sit on respective shelves 116 
hingedly connected to respective opposing side walls 118. The hinges are 
designed to prevent the shelves 116 from rotating below the horizontal 
position in FIG. 21c. The inner edges of the shelves 116 are attached to 
the respective side walls 118 by respective extension springs 120. As the 
eye wash fluid drains from the flexible containers 21, the springs 120 
rotate the shelves 116 in the direction of the arrows so that the shelves 
116 press the flexible containers 21 against the top wail 110 and the 
respective side walls 118. FIG. 21d schematically depicts a CO.sub.2 
bladder method where a bladder 122 is positioned between the flexible 
containers 21 sitting on the stationary shelf 108. The bladder 122 slowly 
expands to maintain pressure on the flexible containers 21 as the eye wash 
fluid is drained therefrom. 
Yet another technique for maintaining a constant fluid flow rate is 
schematically illustrated in FIG. 22. In this technique, pressure is not 
applied to the flexible containers 21. Rather, a deformable flow 
restrictor 126 is connected in the fluid flow path between each flexible 
container 21 and the associated nozzle 22. For example, as depicted in 
FIG. 22, the deformable flow restrictor 126 may be connected to the nozzle 
22, and the hose 24 may, in turn, be connected to an input end of the 
deformable flow restrictor 126. To maintain a constant fluid flow rate as 
the fluid pressure decreases, the deformable flow restrictor 126 contains 
a flexible valve which gradually deforms (opens) as indicated by the 
arrows in FIG. 22. 
In a further alternative embodiment, the self-contained delivery system 
depicted in FIG. 23 may be used as a stand alone eye wash system. As 
illustrated in FIG. 23, in such a stand alone system, the box 20 holding a 
fluid-filled flexible container is hung on a wall or in a vehicle using a 
hanging strap 128. The nozzle 22 is mounted to the box 20 using a retainer 
clip 130. The actuation strap 92 is affixed to the box by adhesive or the 
like. When the stand alone system is needed, the user grabs onto the 
nozzle 22 or hose 24 and pulls, thereby breaking the seal band 86 and 
detaching the pressure plate 76 from the lower nozzle body 78. The user 
holds the lower nozzle body 78 in one hand while rinsing his or her 
eye(s). It should be understood that the stand alone system in FIG. 23 is 
preferably employed as a secondary eye wash station which would allow the 
user to quickly flush his or her eyes until he or she has access to a 
primary eye wash station, such as the eye wash station in FIG. 6. An 
advantage of the stand alone system in FIG. 23 is that it can be readily 
carried in a vehicle or to a remote site. 
To permit the eye wash station 10 to be used in cold-temperature 
environments, the eye wash station 10 may be provided with heating 
elements to maintain the eye wash fluid in a comfortable temperature range 
(70.degree.-80.degree. F.) and prevent freezing thereof. These heating 
elements may be plate heaters arranged to heat the entire interior of the 
eye wash station 10 so that the nozzles 22, the hoses 24, and the flexible 
containers 21 are kept warm. Additionally, an insulating jacket with a 
movable flap (for activation) may cover the exterior of the eye wash 
station 10. 
Each of these embodiments and obvious variations thereof is contemplated as 
falling within the spirit and scope of the claimed invention, which is set 
forth in the following claims.