A lot, 100 grams in the old ones,
Mercury sphygmanometer
every month
The 3 types are: Manual, Digital and Aneroid.
The three types of blood pressure machines are Automatic Sphygmomanometer, Aneroid Sphygmomanometer, and Mercury Sphygmomanometer. The automatic performs automatic functions such as cuff inflation and sophisticated readings. The aneroid consists of a metal bellows that expands on account of increased pressure so the amplifier effects the indicator needle. The mercury is dependent upon the other blood pressure machines for accuracy and calibration.
There is a clear tube where the mercury column is that contains mercury that rises in the tube to read pressure. The rubber tube connected to the reservoir goes to the blood pressure cuff. There is a rubber bulb to fill the cuff and a valve for releasing the air.
mm Hg (milimeters of mercury) usually measured with a Stethoscope and a sphygmomanometer .
because it is less likely to produce inaccurate readings than the electronic versions.
here's a cogent discussion: http://answers.yahoo.com/question/index?qid=20090215214428AAltCZz
Sphygmomanometer (the correct spelling).A Sphygmomanometer is an instrument used to measure an individuals indirect blood pressure. They generally consist of an inflatable cuff that fits around a limb (normally the arm, just above the elbow), a bulb for controlling air pressure within the cuff, and a mercury or aneroid manometer (a dial stating the pressure in millimeters of mercury, mmHg).
Mercury's density is around 13.54 x that of water, so the pressures (in mm of water) would be 13.54 x what they are for mercury - 100 mm Hg would be around 1354 mm H2O
I would love to take the opportunity to answer this question, The sphygmomanometer and BP meter are the same there is no difference.
The real name for a blood pressure cuff is sphygmomanometer.