The exact cause of Erdheim-Chester disease (ECD) is unknown. However, the disease is thought to represent an abnormal inflammatory process characterized by excessive proliferation and accumulation of certain cells, with associated scarring or overgrowth of fibrous connective tissue (fibrosis).
humidity (relative and absolute) The amount of water vapor in the air. Humidity is measured in two ways: (1) Absolute humidity is the percentage of water vapor actually present in the air. (2) Relative humidity is the absolute humidity divided by the amount of water that could be present in the air. Relative humidity indicates the degree of comfort or discomfort one feels from the humidity, because it indicates the amount of perspiration that can evaporate from the skin.
Ideal humidity levels. Humidity is the amount of water vapor in the air. The amount of humidity varies depending on the season, weather and where you live. Generally, humidity levels are higher in the summer and lower during winter months.Ideally, humidity in your home should be between 30 and 50 percent.Humidity that's too low or too high can cause problems.deal humidity levels. Humidity is the amount of water vapor in the air. The amount of humidity varies depending on the season, weather and where you live. Generally, humidity levels are higher in the summer and lower during winter months.