- Interior temperatures exceeding 35°C the equivalent of 0.05% blood alcohol reading, according to SEAT
- A difference of just 10°C could impact reaction times by 20%
- Switching the air-con on full blast without ventilating the car is one of the five most common mistakes
- Air nozzles should be pointed towards the ceiling instead of the occupants
Patience may be a virtue for drivers who want to remain focussed at the wheel as rising temperatures could be impacting driver reaction times.
According to SEAT, common air-con mistakes – including immediately turning the system on full-blast – could be reducing its effectiveness, resulting in higher interior temperatures and possible dehydration.
A difference of just 10°C – 35°C compared to 25°C – inside the cabin can diminish reaction times by 20% – the equivalent to a blood alcohol reading of 0.05%; matching the Scottish limit and close to the maximum of 0.08% for the rest of the UK.
With outside temperatures recently soaring above 30°C in the UK, hurried commuters and holiday-makers in particular could be at risk of dehydration.
Cars parked in the sun can reach a startling 60°C. To help reduce cabin temperatures before setting off and while on the move, the Spanish car manufacturer – based in sunny Barcelona – has published the most common air conditioning mistakes that drivers make:
- Turning on the air conditioning full blast as soon as you get in the car
When entering a hot car, it’s tempting to turn the air-con on to maximum. However, turning on the air conditioning straight away without opening the windows will just recirculate the hot air. Instead, open the doors, lower the windows for a minute or two before shutting the doors and cranking up the A/C.
- Keeping the air recirculation option activated: Keeping it on can make the windows fog and reduce visibility. Most cars will have an ‘Auto’ option, which can regulate itself to prevent fog while keeping drivers and passengers cool.
- Not turning on the air conditioning in the morning: Some summer mornings can be cool, but it’s still a good idea to keep the A/C on to prevent windows from fogging up when the outside temperature rises.
- Pointing the air jets toward you: It’s tempting, but it’s counter-productive and stops the car getting an even distribution of airflow. Pointing the jets upward lets the cool air spread around the car more effectively and allows it to reach all occupants.
- Not performing regular maintenance: Just like the oil, tyres or brake fluid, the air conditioning system requires maintenance. Failing to change clogged cabin air filters every 10,000 to 15,000 miles can stop your A/C working effectively.
Around two-thirds of drivers aren’t aware of the risks of higher temperatures and dehydration*, which can cause tiredness, dizziness, headaches and reduced reaction times.
Engineers at SEAT spend three years developing each model’s cooling system. This time is used to study the geometry of the ducts and vents in 3D, with virtual simulations performed to predict how the air will flow inside the car.
Ángel Suárez, an engineer at the SEAT Technical Centre, says: “Open the doors and lower the windows for a minute before turning on the air conditioning to naturally lower the temperature in the interior.”
If rear passengers say they can’t feel the cool air, then the nozzles could be set incorrectly. “It isn’t a matter of temperature, but in which direction the air is flowing inside the car,” says Suárez. “The nozzles should be pointing upwards, not towards peoples’ faces. Then the air flows all around the interior of the car and reaches every passenger consistently.”