Patent Application
20080058736
The foregoing summary as well as the following description will be better understood when read in conjunction with the figures in which:
Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. A waste disposal container in accordance with the present invention includes a receptacle for receiving and storing medical waste. The receptacle has a bottom wall and one or more side walls that contain a volume of waste. An absorbent body is positioned in the receptacle to capture liquid that leaches or drains from the waste. The absorbent body traps and contains the liquid to minimize the release of the liquid from the container in the event of a container spill or breakage of the container.
According to exemplary embodiments of this invention, an absorbent pad is placed in the bottom of a container to absorb liquid as the liquid accumulates in the container. This has the advantage of preventing liquid leakage before it starts by trapping liquids within the container before the liquid can leak or spill out of the container.
Such an absorbent pad preferably has sufficient absorbent capacity to trap the quantity of liquid associated with some medical waste, which can be considerable. For example, many syringes are known to exhibit a certain volume of dead space, which is the space between the plunger and needle that contains residual liquid after the plunger is fully advanced to release the contents in the syringe. Assuming a typical dead space of 5% common to all wastes placed in the container, and assuming those dead spaces to be occupied by liquid, the desired absorbency would be at least about 5 percent of the volume of the container. For an 8 gallon container, this would be 0.4 gallons, or approximately 1,500 cubic centimeters.
One approach to achieving an increased absorption capacity is to simply increase the amount of surface area of absorbent padding used in the bottom of the container. If the absorbent capacity of a single pad is insufficient, two or more absorbent pads are placed in the container until the bottom of the container is entirely covered or substantially covered with absorbent padding. This approach may have limitations in certain applications, however. For example, adding absorbent material adds to the unit cost of each container. In addition, many containers are molded with bottoms that are not flat. For example, some containers have a generally rectangular shape with rounded corners. These surfaces make it very difficult to cover the bottom surface of the container with absorbent padding, while keeping the padding in a flattened stable condition. If the pad is not stable, the pad could be shifted and bunched into positions that do not properly absorb liquid from the bottom of the container where it accumulates.
The use of multiple pads in a container may require opening and handling multiple pads. Maintenance workers and medical staff, for a variety of reasons, may therefore fail to place all the desired pads in the container. For example, personnel may be inclined to save one or more of the pads under the mistaken assumption that only one pad is required in the container. Therefore, though viable, increasing the number of absorbent pads in the container may have drawbacks that take away from the effectiveness of this option in certain applications.
According to another exemplary embodiment of the invention, the absorbent body features an increased absorption capacity in combination with a reduced overall size relative to the bottom of the receptacle. The reduced size allows the absorbent body to rest flatly on the bottom of the receptacle, with minimal or no voids created between the pad and the container bottom. The reduced size also reduces the unit cost of the container. At the same time, the increased absorption capacity of the pad accommodates the amount of liquid leachate that is typical from dead space syringes, IV bags, and other common medical waste.
Referring to the drawing Figures generally, and to
Bottom wall 22 has a length 52, a width 54, and an interior surface area 23 having a substantially flat surface contour. As is typical of many waste receptacles, the large majority of interior surface area 23 includes a substantially planar or flat central area 24. The flat central area 24 is surrounded by a non-planar perimeter region, which in
The container of the present invention further includes an absorbent body inserted into the receptacle. Referring to
Pad 30 has a surface area 35 that is confined within the flat central area 24 of the bottom wall 22. In this arrangement, the entire pad 30 rests flatly on the bottom wall 22. For purposes of this description, the surface area 35 of the pad refers to the area of the pad as measured within the four sides that make up the perimeter 37. The surface area is equal to the length 38 times the width 39.
The container 10 has an absorbent body that makes it possible to provide the required absorbency without assuming a large surface area. The absorbent pad has enhanced absorbent properties that reduce the amount of absorbent material required to be placed in the container. Referring to
Absorbent pad 30 has the capacity to absorb a volume of free liquid that is in line with the free liquid volumes observed in medical waste containers. In the preferred embodiment, absorbent pad 30 has an absorbency of at least about 20 cubic centimeters of water per square inch, more preferably an absorbency of at least about 25 cubic centimeters of water per square inch, and still more preferably an absorbency of at least about 30 cubic centimeters of water per square inch.
The absorbency data provided herein was obtained through a series of tests in which water was applied to a pad in its dry state under room temperature and atmospheric pressure. Water was poured onto the pad until the pad reached a point of saturation; that is, the point beyond which any additional liquid poured onto the pad resulted in free liquid accumulating around the pad. The volume of water that was poured up to the saturation point was determined to be the total volume absorbed. The total volume absorbed was then divided by the surface area of the pad to determine the absorbency values in cc/square inch.
Waste disposal container 10 has a ratio of absorption capacity of the pad to the volume of the container. The ratio of the absorption capacity of the pad to the volume of the container is preferably at least about 2 percent, more preferably at least about 3 percent, still more preferably at least about 4 percent, and still more preferably at least about 5 percent.
The waste container may use a variety of absorbent pad configurations. While a variety of pad sizes can be selected within the scope of the present invention, two basic sizes have been found suitable for use with a broad range of container sizes. In one size, absorbent pad 30 has a total surface area of about 18 square inches or less. For example, absorbent pad 30 may have a length of about 6 inches or less and a width of about 3 inches or less. This size has been found most suitable for 2 and 3 gallon containers, although the size may be appropriate for other container sizes as well. In another embodiment, absorbent pad 30 has a surface area of about 60 square inches or less. For example, absorbent pad 30 may have a length of about 10 inches or less and a width of about 6 inches or less. This size has been found most suitable for 8, 12 and 18 gallon containers, although the size may be appropriate for other container sizes as well, including but not limited to 19 gallon and 30 gallon containers. For larger containers, i.e. containers larger than 18 gallons, it may be desirable to provide more than one pad, depending on the application, in order to further increase the absorption of free liquid in the container. The selection of pad size may also be made based on relative surface area. For example, a ratio of surface area of the pad to surface area of the bottom wall of about 0.2 may be used to provide adequate absorption for many categories of waste.
The effective storage capacity of medical waste containers is typically represented by a fill line placed on the container or a label placed onto the container. The fill line is commonly placed three-quarters of the way up the height of the container, measured from the bottom. Medical personnel are instructed not to place any waste in the container once the volume of waste in the container rises to the fill line. In view of this restriction, the effective capacity of a waste container is influenced by the height of any pads that are placed on the bottom of the container, as the pad or pads will occupy some amount of volume that would otherwise be occupied by waste. The presence of highly absorbent SAP has the advantage of providing a large absorption capacity in a pad having a significantly reduced pad thickness. In a preferred embodiment, pad 30 has a very small thickness so as to minimize the amount of space the pad occupies at the bottom of the container. This is advantageous to the user, as it increases the overall storage capacity of the container. Because the pad 30 has a very small thickness as compared to known absorbent pads, the pad has less height and therefore takes up less volume in the container, leaving more room for waste. As a result, more waste can be placed in the container, reducing the frequency of replacement and disposal of waste containers over time. Pad 30 preferably has a thickness in the dry state of about ⅛ inch or less, more preferably about 1/16 inch or less, and even more preferably about 1/32 inch or less.
Bottom wall 22 has a surface area 23 that is adapted to receive absorbent pad 30 in a flat condition with clearance around the perimeter, as noted above. In one exemplary embodiment, absorbent pad 30 is held in place in the central area 24 of bottom wall 22 by a securement means. The securement means may be a fastener integrally molded to the bottom wall of the container, including but not limited to a clip, hook or tab fixture that holds down the edges of pad 30. Referring to
The medical waste containers of the present invention may be sold and packaged as a single unit. For example, the waste containers may be sold in a package containing a single receptacle and a single absorbent pad placed in the receptacle. Where applicable, other accessories may be included in the packaging, such as a lid for the receptacle and/or components for mounting the receptacle to a wall or other support structure.
The absorbent pad may be individually wrapped and placed in the packaging with the container. Upon setting up the container, the user would unpack the receptacle and the pad, unwrap the pad, and place the pad into the bottom of the receptacle. If the pad is attachable to the bottom of the receptacle, as for example by an adhesive, the user would apply the unwrapped pad to the bottom of the receptacle with the adhesive side face down onto the bottom of the receptacle.
Absorbent padding is commonly manufactured in rolls and subsequently cut into sheets of specific sizes. Depending on the particular product or end use, the individual absorbent sheets may be packaged in sets of 5, 10, or some other grouping arrangement. Where absorbent pads are supplied from a third party, it has been found beneficial to manufacture and sell the medical container in kits containing multiple receptacles and pads. For example, the medical waste container of the present invention may be sold as a kit containing two or more receptacles and two or more corresponding absorbent pads for placement into the receptacles. A kit arrangement makes it easier to incorporate sets of absorbent pads into the product. Selling containers individually is also an option, but may require opening sets of absorbent pads to separate out individual pads. This separation step may not be desirable as it adds an additional step in the production process.
Referring to
Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.
