Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Bone Marrow or Hematopoietic Stem Cell Transplant


How Procedure is Performed

The first step of stem cell transplant is to establish the closest match between donor and recipient cells. Once a potential donor has been identified, the candidate must first undergo extensive blood testing to confirm the absence of disease and to verify the suitability of the match. Clearly, a donor who is an identical twin of the recipient (syngeneic transplants) is the most ideal match. Harvesting from the recipient's sibling (allogeneic transplant) provides the next best match. Harvesting from unrelated donors (unrelated donor transplant) is possible, but requires lengthy blood testing that may take up to 4 months to find a suitable match. Even with careful matching, unrelated donor transplants have higher rates of complications.

Sources of hematopoeitic stem cells include the bone marrow, the peripheral blood and umbilical blood. To harvest stem cells from the bone marrow, the donor receives general anesthetic, a needle is inserted in the marrow of the iliac crest (hip bone) and the marrow is withdrawn.

Hematopoietic stem cells can also be harvested from the peripheral blood for either autologus transplants or allogeneic transplants. A hematopoietic growth factor is administered to the donor (or recipient in the case of autologus transplant) to trigger the release of stem cells from the bone marrow to the bloodstream. Blood, rich in stem cells is then collected, processed and later administered to the recipient when needed. This source is often preferred over the bone marrow collection because it does not require anesthesia and its associated risks.

Stem cells may also be collected from the umbilical cord at the time of delivery, processed and stored for future use in allogeneic transplants or unrelated donor transplants. The cord blood is rich in stem cells and because the immune system is immature at birth this source has fewer post transplant rejection than other sources. One limitation is that only a small volume may be collected from the umbilical cord.

After a suitable donor is selected and stem cells are harvested, the recipient must go through a preparative regime that suppresses the recipient's immune system enough to prevent rejection and to eliminate the underlying disease. This may involve the administration of maximally tolerated doses of chemotherapy drugs and possibly radiation therapy. The preparative regimen is associated with significant side effects and complications. To minimize the side effects and complications, a new regimen called "sub-ablative" or "mini" transplants is being used in some cases, which uses lower doses of drugs together with radiation to provide adequate immune suppression for successful transplantation.

Once the recipient has completed the preparative regimen, they receive an intravenous infusion of the stem cells (without the use of a blood filter). Hospitalization and close monitoring for complications of transplantation such as graft rejection or infection is needed for several days to weeks. Antibiotics and transfusions may be administered during this time to help prevent and fight infection. Blood elements will need replacing if anemia, leukopenia, or thrombocytopenia occur before the bone marrow "takes" (engraftment).

Source: Medical Disability Advisor