In order to obtain an accurate reading, an appropriately sized blood pressure cuff should be used. Appropriate cuff size can be determined by one of the following methods:

Estimate the circumference of the upper arm at midpoint between shoulder and elbow. The bladder inside the cuff should encircle at least 80 % of the arm circumference

The width of the cuff should be 20 % more than the diameter of the arm. The cuff should be placed so that the midline of the bladder is over the arterial pulsation.

A guide to the correct width of the cuff :

• 3 cm - infant
• 6 cm - child
• 9 cm - small adult
• 12 cm - medium adult
• 15 cm - large adult cuff