What is heat stroke?
The human body can regulate internal temperature within safe limits spontaneously. When we get hotter, the temperature control centre inside our body will trigger responses such as sweating and increasing breathing rate to cool us down. However, when the environment becomes extremely hot and spontaneous responses cannot effectively cool down our body, heat exhaustion or even heat stroke will occur.
Symptoms of heat exhaustion include giddiness, headache, nausea, shortness of breath and mental confusion. When the body temperature reaches 41°C or higher, the sufferer will have convulsion or become unconscious; and this is heat stroke. Immediately, the body temperature must be brought down and first aid be given, or else the sufferer’s life will be in great danger.
Who is at risk?
- The obese
- The Sick
- The elderly
Pay attention to the weather warning issued by the Hong Kong Observatory and take the following measures:
- Wear light-coloured, loose and air permeable clothing to reduce heat absorption and promote heat loss from sweating.
- Bring and drink plenty of fluid to prevent dehydration.
- Avoid drinks containing caffeine (e.g. coffee and tea) or alcohol, because these substances will speed up water loss from the body through the urinary system.
- Do not engage in prolonged activities such as hiking and trekking under extremely hot weather, as heat, sweating and exhaustion place additional demands on one’s physique.
- Perform outdoor activities in the morning or late afternoon, if possible.
- Choose an indoor venue with good ventilation by opening all windows and using fan or air-conditioning. Avoid doing vigorous exercise in a hot or stuffy environment.
- Re-schedule your work to cooler times of the day. If you must work in a hot environment, introduce shading in the work area where practicable, then start slowly and pick up the pace gradually. Take breaks every now and then in a cool area to recharge yourself.
- Do not stay inside a parked vehicle.
- Stop in the course of activity immediately and seek medical advice if feeling unwell.