A bottle on the parcel shelf, a laptop on the passenger seat, a toolbox in the boot: as long as the car is rolling, none of it is a problem. The problem appears at the exact moment it stops without warning.<\/p>\n
The essentials<\/p>\n
When a car hits an obstacle, it stops over the length it is able to deform: about half a metre for a modern car at 50 km\/h. The occupants, held by belts and airbags, stop with it.<\/p>\n
Whatever is not attached carries on at 50 km\/h. It will only stop when it meets something: a seat back, a headrest, someone's neck.<\/p>\n
The arithmetic is not mysterious. Going from 13.9 metres per second to zero over half a metre is a deceleration of roughly twenty times gravity. An object therefore takes a force equal to twenty times its weight.<\/p>\n
These are not brochure figures: it is elementary arithmetic, and it is why safety testing has long called for restraint nets behind the seats of estate cars.<\/p>\n
The parcel shelf.<\/strong> The worst place in the cabin: nothing holds the object, it sits at head height, and it crosses the whole interior in a straight line. People still put tissue boxes, umbrellas and speakers there.<\/p>\n The passenger seat.<\/strong> An unused belt holds nothing at all, and a bag put there heads for the windscreen or the footwell — where your pedals are, including during a merely firm braking.<\/p>\n The boot of an estate or an SUV with no cover.<\/strong> With no net and no bulkhead, the boot is open to the cabin. A suitcase there has the whole length of the car to accelerate before meeting a seat back.<\/p>\n The general rule fits in one sentence: the heavier it is, the lower, further back and more wedged in it must be.<\/p>\n A hook is obviously not an approved safety device, and we do not sell it as one: it keeps a bag from lying around and sliding under the pedals. To carry something heavy and hard, the only right answer is still the boot floor.<\/p>\n In the back, the danger rarely comes from a forgotten object: it comes from what we hand children during the trip. A tablet held at arm's length, a metal flask, a rigid toy. Prefer soft and light, and keep the rest in a seat-back pocket rather than on the bench.<\/p>\n For a dog, no amount of storage replaces a safety harness or a secured crate. An unrestrained twenty-kilo animal represents, in a 50 km\/h crash, the equivalent of four hundred kilos thrown forward.<\/p>\n There’s no article that names « an object left on a seat » specifically. What exists is broader, and stricter than most people think.<\/p>\n Article R412-6 requires the driver to remain at all times able to carry out, easily and without delay, all the maneuvers required of them. An object rolling toward the pedals, a load shifting, an animal moving around the cabin: all of this falls under this rule, and the fine can reach a flat penalty of 135 euros.<\/p>\n A second rule concerns the load itself: it must not cover the lights and license plate, must not compromise the vehicle’s stability, and must not block the driver’s view. A trunk loaded up to the ceiling, fully blocking the rear window, falls under this.<\/p>\n Finally, a point insurers know well: after an accident, an unsecured object can be brought up in the liability assessment. The debate then centers on your compensation, months later, based on the paperwork.<\/p>\n These orders of magnitude explain something counterintuitive: it’s not the size of the object that matters, it’s its mass and hardness. A half-liter metal bottle is more dangerous than a large cushion, because it concentrates its energy on a few square centimeters.<\/p>\n On a sedan, the trunk is a separate compartment: a suitcase thrown forward hits the rear seat and stops there. On a wagon, a minivan or an SUV, the trunk and the cabin form a single volume, and nothing stands in the way.<\/p>\n Three levels of protection, from most effective to lightest:<\/p>\n SUV Trunk Storage Net \u2014 51,99 \u20ac<\/strong>Holds bags and loose items across the full width of the trunk.<\/span><\/a><\/p>\n This isn’t about fitting out your car, it’s about deciding once and for all where everything goes. Go through it, just once, in this order:<\/p>\nWhat works, in order<\/h2>\n
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Children and animals<\/h2>\n
What the traffic code says<\/h2>\n
What each object really weighs<\/h2>\n
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\n \nObject<\/th>\n Actual weight<\/th>\n Force on impact<\/th>\n<\/tr>\n<\/thead>\n \n Phone<\/th>\n 0,2 kg<\/td>\n 4 kg<\/td>\n<\/tr>\n \n Water bottle<\/th>\n 1,5 kg<\/td>\n 30 kg<\/td>\n<\/tr>\n \n Laptop<\/th>\n 2 kg<\/td>\n 40 kg<\/td>\n<\/tr>\n \n Shopping bag<\/th>\n 5 kg<\/td>\n 100 kg<\/td>\n<\/tr>\n \n Medium-sized dog<\/th>\n 15 kg<\/td>\n 300 kg<\/td>\n<\/tr>\n \n Toolbox<\/th>\n 10 kg<\/td>\n 200 kg<\/td>\n<\/tr>\n \n Checked suitcase<\/th>\n 20 kg<\/td>\n 400 kg<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n The trunk of a wagon or an SUV<\/h2>\n
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The five minutes that solve the problem<\/h2>\n
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