A standard twin mattress is 39 by 75 inches. A king is 76 by 80 inches. This means that a headboard for a king bed is going to be about 76 inches or wider, plenty wide enough to go along the length of a twin bed. Headboards are often slightly wider than the bed for which they are made.
Hemoglobin, Hematocrit, Blood Count. In order to donate blood, a woman must have a hemoglobin level of at least 12.5 g/dL, and a man must have a hemoglobin level of at least 13.0 g/dL. For all donors, the hemoglobin level can be no greater than 20 g/dL.
To protect patients from unsuitable blood and blood products, the FDA has required blood donors to answer specific questions about risk factors that could affect the safety of the donation. FDA requires blood centers to maintain lists of unsuitable donors to prevent further donations from these individuals and that blood is tested for several infectious agents after donation. All tests must be negative before the blood is suitable for transfusion. The agency also inspects all blood facilities at least every two years.