5. Measurement procedure
Please note: You should always be seated before and during measurement.
5.1. Before measurement:
• Avoid eating and smoking as well as all forms of exertion directly before measure-
ment. These factors influence the measurement result. Find time to relax by sitting in
an armchair in a quiet atmosphere for about ten minutes before your measurement.
• Remove any garment that fits closely to your upper arm.
• Always measure on the same arm (normally left).
• Compare measurements at the same time of day, since blood pressure changes
during the course of the day (as much as 20–40 mmHg).
5.2. Common sources of error
Note: Comparable blood pressure measurements always require the same
conditions. Conditions should always be quiet.
• All efforts by the user to support the arm can increase blood pressure. Make sure
you are in a comfortable, relaxed position and do not flex any of the muscles in the
measurement arm during the measurement. Use a cushion for support if necessary.
• If the arm artery lies considerably lower or higher than the heart, an erroneously
high or low blood pressure will be measured. Each 15 cm (6") difference in height
between your heart and the cuff results in a measurement error of 10 mmHg.
• Cuffs that are too narrow or too short result in false measurement values. Selecting
the correct cuff is extremely important. Cuff size is dependent upon the circumfer-
ence of the arm (measured in the center). The permissible range is printed on the
cuff. If this is not suitable for your use, please call 1-800-568-4147.
• A loose cuff or a sideways protruding air pocket causes false measurement values.
• With repeated measurements, blood accumulates in the arm, which can lead to
false results. Consecutive blood pressure measurements should be repeated after a
1 minute pause or after your arm has been held up in order to allow the accumulated
blood to flow away.
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