Sphygmomanometers are machines that require manual inflation of a cuff that wraps around the upper arm and the readings are taken when the pulse stops due to the inflated pressure and when it returns as the cuff is slowly deflated.
Increasingly, for ease of use and greater accuracy, fully automatic digital machines are used and measure blood pressure correctly on the upper arm at heart level.
The National Institutes of Health continues to recognize blood pressure measurement by auscultation as the gold standard. For instructions and case studies using an online simulated patient, use the link below.