Long blow "220V AC Cooling Fan", especially when using high-speed gear, skin capillaries will shrink, increasing peripheral vascular resistance, will increase the burden on the heart. Head rich in blood vessels, blood flow more sensitive to cold stimuli, if his head blown "220V AC Cooling Fan", can lead to headaches, dizziness, fatigue and discomfort. In addition, long time at the fan blowing, body temperature with a lot of sweat evaporation decreases, prone to colds, flu, abdominal pain, diarrhea and other diseases. Usually every blow "220V AC Cooling Fan" for half an hour to one hour is appropriate, while the best open the windows to keep the air circulating.