Otherwise, if furnace flue is being abandoned because no longer needed, I would require the top be removed and replaced with a domed galvanized metal cap to keep insects and maybe rodents from taking up residence or using it as a nut cache - cost probably about $50-75 additional.
The creatinine levels in both urine and blood are determined and compared. Normal creatinine clearance for healthy women is 88-128 mL/min. and 97 to 137 mL/min. in males (normal levels may vary slightly between labs). Blood urea nitrogen (BUN) level is another indicator of kidney function.
Creatinine is a waste product that comes from the normal wear and tear on muscles of the body. Creatinine clearance test compares the creatinine in a 24-hour sample of urine to the creatinine level in your blood to show how much waste products the kidneys are filtering out each minute.