Blood pressure is measured by using sphygmomanometer

Step2

An inflatable cuff is placed around the upper arm and inflated until all blood flow,in or out of the arm stops. The blood flow is monitored using a stethoscope.

Step2

After inflation,there is no sound but as air escapes from the cuff, the pressure decreases until it falls just below the pressure of the heart as the contracts. This is systolic pressure.

Step3

pressure in the cuff continues to drop until the blood can be heard flowing constantly. This is the diastolic pressure.

Note:Normal blood pressure of adult is 120/80mmHg