Shutting yourself away in a car cabin where the temperature is above 35 degrees is like starting to drive after having drunk alcohol: the suffocating heat slows down the flow of blood to the brain, to the equivalent of a blood alcohol level of 0.5g per litre. This means a reduction in the rapidity of reflexes, a greater risk of somnolence and in general diminished lucidity. This is why it is important to take all possible precautions in order to drive safely even when the thermometer is showing that alarm levels have been exceeded.
BEFORE STARTING YOUR JOURNEY
When temperatures reach extreme levels, tyre pressure can change: whilst it is always important to make periodic checks of tyre pressures, it becomes a fundamental requirement to do so – when the tyres are cold – before driving away in the car for a holiday. It is preferable to take a look at the level of air conditioning gas and the cleanliness of the air filters so that you can breathe the cleanest possible air, given that the air conditioning unit will very probably be your most trusted companion for the journey. Then there are various liquids which need to be checked, in particular the one contained in the radiator cooling system. In order to avoid incurring bouts of sleepiness or digestive problems, it is best to avoid alcohol and over-generous portions at mealtimes, but nor do you need to go without food for more than 2-3 hours at a time.
ALSO READ: Is tread wear regular? How to check it
THE AIR CONDITIONING UNIT, FRIEND AND FOE
A classic situation: you leave the car parked in the sun, you come back after a few hours and you cannot face the prospect of sitting down on the burning seat. What is the best thing to do in such a case? Leave the windows or the doors open for around 30 seconds, because in this way the air inside the cabin, which is much hotter and thus lighter than the air outside, will rush out and the temperature inside the car will fall to close to that of the air outside.
After that, it would be a good idea to put just the fan on, and then gradually to launch the air conditioning until the required power level is reached. If the outside temperature is more than 30 degrees, you need to set the air conditioning to a temperature which is no lower than 21 degrees, both to avoid excessive fuel consumption (the air conditioning unit takes power away from the engine), and in order not to cause a thermal shock which could potentially damage your health. Selecting the “auto” setting – if it is available – is the best choice for regulating the temperature in the cabin. Furthermore, it is best to avoid pointing the air conditioning vents directly at yourselves: this reduces the risk of muscular pains, which are often attributed to cold air.
DURING THE JOURNEY
Clearly, it would be preferable to tackle long journeys during the coolest hours of the day, but if this is not possible there are some prudent habits to be adopted in order to avoid suffering from the heat. Do not forget to carry water with you, for yourself, for the other passengers and for any animals which are travelling with you. The latter must never be left shut in a parked car, because after merely a few minutes the temperature in the cabin can soar to levels which are lethal.
If it is not too hot, open the windows to renew the supply of oxygen. If you are travelling with young children, make sure that you protect them from the sun’s rays, and do not forget that you can also get sunburnt in a car: you need to apply sun cream and wear sunglasses to avoid tiring your eyes too much. Finally, do not commit the mistake of leaving the engine running when you are parked in order to keep the air conditioning working, because this can result in a penalty notice.