The applicability of FAR 121.377 is not eliminated by a person's performing a mix of work such as you describe. Such an interpretation would defeat the purpose of the regulation which is to insure that person's performing part 121 maintenance or preventive maintenance are provided relief from duty.
The cause of rheumatoid arthritis is unknown, although it appears to be an autoimmune disease. When the body's immune system does not operate as it should, white blood cells that normally attack bacteria or viruses attack healthy tissue instead â in this case, the synovium, or joint tissue.
Rheumatoid arthritis (RA) is an inflammatory disease that causes pain, swelling, stiffness, and loss of function in the joints. It occurs when the immune system, which normally defends the body from invading organisms, turns its attack against the membrane lining the joints.ike many other rheumatic diseases, rheumatoid arthritis is an autoimmune disease (auto means self), so-called because a personâs immune system, which normally helps protect the body from infection and disease, attacks joint tissues for unknown reasons.