Heat wave alert.
Please note over the next few days, there will be a heat wave in St George QLD with temperatures reaching 43 degrees.
Friday Highs of 40 degrees
Saturday Highs of 42 degrees
Sunday Highs of 42 degrees
Monday Highs of 38 degrees
Tuesday Highs of 41 degrees
How to survive the heat wave…
- Stay hydrated by drinking plenty of fluids even if you do not feel thirsty. Avoid drinks with caffeine or alcohol.
- Eat small meals and eat more often.
- Avoid extreme temperature changes.
- Wear loose-fitting, lightweight, light-coloured clothing. Avoid dark colours because they absorb the sun’s rays
- Sun Hats Broad brimmed hat, SPF 30+ sunscreen (as per manufactures instructions) when working outside. To help provide protection against the Sun
How the body controls heat gain and heat loss
The human body gains and loses heat in two ways:
- body heat – the internal heat generated by metabolic processes
- exchange with the environment – the body exchanges heat with its surroundings mainly through:
- radiation - the process by which the body gains heat from surrounding hot objects (e.g. hot metal, furnaces or steam pipes), and loses heat to cold objects (e.g. chilled metallic surfaces) without contact with them
- convection – the process by which the body exchanges heat with the surrounding air. The body gains heat from hot air and loses heat to cold air which comes in contact with the skin
- evaporation of sweat – the cooling effect is more noticeable with high wind speeds and low relative humidity. In hot and humid workplaces, the body cooling due to sweat evaporation is limited because the air cannot absorb more moisture. In hot and dry workplaces, the cooling due to sweat evaporation is limited by the amount of sweat produced by the body.
- The body also exchanges small amounts of heat by conduction and breathing, which can usually be discounted when assessing the heat load on the body
Not everyone reacts to heat in the same way
The way heat affects people varies from person to person and is influenced by:
- general health
- body weight (being overweight or obese can make it more difficult to cope with heat)
- age (particularly for people about 45 years and older)
- poor general health
- a low level of fitness will make people more susceptible to feeling the extremes of heat
- certain prescription and illicit drug use
- medical conditions (can also increase how susceptible a person is). People with conditions such as heart disease, high blood pressure, pregnancy, respiratory disease and diabetes may need to take special precautions. In addition, people with some types of skin diseases and rashes may be more susceptible to heat.
- Other factors include circulatory system capacity, sweat production and the ability to regulate electrolyte balance
People have an average core body temperature of around 37˚C. In hot environments, or where internal temperature is raised through exercise for example, body responses include:
· vasodilation (widening of blood vessels)
· increased respiratory rate
· increased heart rate.
Responses due to heat-strain
· electrolyte changes
· elevated core temperature.
Excessive heat-strain can occur when the work environment, task or individual health prevent these cooling mechanisms from working properly, and can lead to heat-related illnesses including:
- Heat rash – sometimes called ‘prickly heat’. It is a skin irritation caused by excessive sweating and
- can occur at any age
- is most commonly associated with humid /dusty tasks in which the skin pores become blocked
- looks like a red cluster of pimples or small blisters
- is most likely to occur on the neck and upper chest, and in skin folds and creases
- Heat cramps – these include muscle pains or spasms, usually in the abdomen, arms or legs. They may occur after strenuous activity in a hot environment, when the body gets depleted of salt and water. They may also be a symptom of heat exhaustion.
- Dizziness and fainting – heat related dizziness and fainting results from reduced blood flow to the brain. Heat causes an increase in blood flow to the skin and pooling of blood in the legs, which can lead to a sudden drop in blood pressure.
- Heat exhaustion – is a serious condition that can develop into heatstroke. It occurs when excessive sweating in a hot environment reduces the blood volume. Warning signs may include paleness and sweating, rapid heart rate, muscle cramps (usually in the abdomen, arms or legs), headache, nausea and vomiting, dizziness or fainting.
is a medical emergency and requires urgent attention.
Heatstroke occurs when the core body temperature rises above 40.5 °C and the body’s internal systems start to shut down.
Many organs in the body can suffer damage and to rectify it, the person’s body temperature must be reduced quickly.
Most people will have profound central nervous system changes such as delirium, coma and seizures. The person may stagger, appear confused, have a fit or collapse and become unconscious.
As well as effects on the nervous system, there can be liver, kidney, muscle and heart damage.
The symptoms of heatstroke may be the same as for heat exhaustion, but the skin may be dry with no sweating and the person’s mental condition worsens.
If you do not feel well please report to your supervisor or first aider immediately.