Heat Stroke Prediction” and “Estimated Emergency Transport
Emergency transportation due to heat stroke is still continuing throughout the country.
In the week of July 16th – 22nd, the number of people who were transported to hospitals due to
heatstroke rose to 22,447, the highest figure recorded since 2008 when the statistic started
In the meantime, on July 20, the Japan Emergency Medical Society announced an emergency
directive on heat stroke prevention. The contents are as follows.
① Try to stay consistently aware of the heat index, and make the appropriate decision whether
to stop exercising and working!
② Get hydrated frequently. If you think you feel something is wrong with you, get to a cool place
③ Make proper evaluation on the severity and apply first aid measures: Observe, and if the
person’s condition does not improve, immediately take them to a medical institution.
④ Everyone in the area should look out for each other!
Take note for everyday activity! What is the “heat index”?
The term “heat index” appears as one of the recommendations. There are many people who are
seeing it for the first time.
This is “WBGT (Wet Bulb Globe Temperature): Wet bulb globe temperature” is an index that
combines three factors: temperature, humidity, and radiant heat (ground, buildings, heat from
We are computing whether it is an external environment where heat stroke is likely to occur at
the ratio of “temperature: humidity: radiant heat = 1: 7: 2”. Whether heat stroke is likely to occur
can not be determined by the temperature alone, and the higher the heat index, the higher the
risk of heat stroke.
“Hazard = exercise is expressly prohibited” when the heat index exceeds 31 ° C, “extreme
caution = heavy exercise should be discontinued” from 28 to 31 ° C, “warning = rest from
activity” from 25 to 28 ° C.
Since the actual condition and forecast of the heat index in various parts of the country are
published in Ministry of the Environment’s “Heat Stroke Prevention Information Website”
(http://www.wbgt.env.go.jp/), please refer to it .
● Ministry of the Environment, Ministry Health Heat Stroke Prevention Information Site
“Heatness Index (WBGT) Commentary and Forecast”
What is the condition where you should call for an ambulance?
In the third of the recommendations, there is “appropriate severity judgment and first aid”.
What exactly is “appropriate”?
If you suspect the symptoms of heat stroke (dizziness, syncope, massive sweat, headache,
discomfort, nausea · vomiting, malaise, disruption of consciousness, cramping, spasm of limbs,
hyperthermia etc), move to a cool place first. Then, loosen the clothes and cool the body.
In event of condition below:
· If the person is unconscious
· If the person can not hydrate without assistance
· If the person can hydrate without assistance but their physical condition does not improve,
call for an ambulance.
It is generally accepted that “all symptoms disappear in about 5 minutes” is a measure of
Precautions are the key, but if you have a heat stroke, first take a break in a cool place and if
you do not recuperate, please call for an ambulance immediately.