NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected
by absorption and reflection from structures, objects and people.
8
．
About Blood Pressure
8.1 What is Blood Pressure?
Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels,
and is one of the principal vital signs.
Two pressures are measured for a blood pressure reading:
Systolic blood pressure is a measure of blood pressure while the heart is beating.
Diastolic pressure is a measure of blood pressure while the heart is relaxed.
8.2 What is high blood pressure?
High blood pressure, also known as HBP or hypertension, is a widely misunderstood medical
condition. Some people think that those with hypertension are tense, nervous or hyperactive, but
hypertension has nothing to do with personality traits. The truth is, you can be a calm, relaxed
person and still have HBP. Let's look at the facts about blood pressure so you can better
understand how your body works and why it is smart to start protecting yourself now, no matter
what your blood pressure numbers are.
By keeping your blood pressure in the healthy range, you are:
Reducing your risk of your vascular walls becoming overstretched and injured
Reducing your risk of your heart having to pump harder to compensate for blockages
Protecting your entire body so that your tissue receives regular supplies of blood that is rich in
the oxygen it needs
According to World Health organization standard, the blood pressure level classification and
definition as following:
Category
Systolic
（
mmHg
）
Diastolic
（
mmHg
）
Desirable
120 and
80
Normal
120-129 and/or
80-84
Pre hypertension
130-139 and/or
85-89
Hypertension
：
≥140 and/or
≥90
Stage 1 Hypertension
140-159 and/or
90-99
Stage 2 Hypertension
160-179 and/or
100-109
≥180 and/or
≥110
These categories were defined by the American Heart Association. This chart applies to adults
age 20 and older.
