For dry-type transformers having a 220 [degrees] C insulating system and a winding hot-spot temperature of 220 [degrees] C, and with no unusual operating conditions present, the 20-yr life expectancy is a reasonable time frame.he 80 [degrees] C transformer requires operation at 75% or more of full load for a 2-yr payback, and at 100% load to payback in 1 yr over the 150 [degrees] C transformer.
Exposure to arsenic through drinking water is a great threat to human health. Arsenic is a carcinogen and its consumption can negatively affect the gastrointestinal tract and cardiac, vascular and central nervous systems.
Inorganic forms are more toxic than organic forms of arsenic; generally arsenite (+3) is more toxic than arsenate (+5). Signs of inorganic arsenic toxicity include dermatosis, hematopoietic depression, liver damage, sensory disturbances, peripheral neuritis, anorexia, and skin and internal cancers.